CRWR Online Report 00 - 3
An Analysis of a Methodology for Generating
Watershed Parameters using GIS
by
David Mason, MSE
Graduate Research Assistant
and
David R. Maidment, PhD.
Principal Investigator
May 2000
CENTER FOR RESEARCH IN WATER RESOURCES
Bureau of Engineering Research ? The University of Texas at Austin
J.J. Pickle Research Campus  Austin, TX 78712-4497
This document is available online via World Wide Web at
http://www.crwr.utexas.edu/online.html
Copyright
by
David Mason
2000
iii
Acknowledgements
First, I would like to thank my advisor, Dr. David Maidment, and Dr. Francisco
Olivera for their generous support and guidance throughout this research. The
study presented in this report was funded by the Texas Natural Resource
Conservation Commission. Their support is gratefully acknowledged.
I would also like to thank Dr. David Kibler, my former professor at Virginia
Tech, for providing me the inspiration to continue my interest in hydrology and
engineering in graduate school.
Last, but certainly not least, I would like to thank my family and friends for their
patience and support throughout my academic career. Without you, I would not
be where I am today.
May 5, 2000
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Abstract
An Analysis of a Methodology for Generating Watershed
Parameters Using GIS
David Mason, M.S.E
The University of Texas at Austin, 2000
Supervisor: David Maidment
A basic methodology is presented for generating watershed parameters in
a GIS format. The calculation of drainage area, average curve number, and
average precipitation parameters were made for water right locations as part of the
TNRCC?s Water Availability Modeling project for the Nueces, Guadalupe, San
Antonio, and San Jacinto river basins. The effectiveness of the methodology was
analyzed. The study showed that 90-meter (1:250,000 scale) DEMs alone could
not be used to accurately delineate watersheds. However, 30-meter (1:24,000
scale) DEMs were used to accurately delineate watersheds ranging from a size of
10,000 square miles to 0.15 square miles in areas with well-defined drainage. The
limitations of using 30-meter DEMs were a 10-fold increase in both file size and
processing time. Also, the increased resolution of the DEMs still had difficulty
defining accurate watersheds in areas with an average slope of less than 0.002
m/m.
v
TABLE OF CONTENTS
LIST OF TABLES ............................................................................................ IX
LIST OF FIGURES.............................................................................................X
CHAPTER 1: INTRODUCTION .........................................................................1
1.1 Background................................................................................................1
1.2 Objectives ..................................................................................................4
1.3 Study Area .................................................................................................5
1.4 Methods.....................................................................................................6
1.5 Outline .......................................................................................................7
CHAPTER 2: LITERATURE REVIEW...............................................................8
2.1 Introduction................................................................................................8
2.2 Terrain Analysis.........................................................................................8
2.3 Conclusion ...............................................................................................12
CHAPTER 3: SYSTEM AND DATA DESCRIPTION ..........................................14
3.1 Introduction..............................................................................................14
3.2 Geographic Information Systems..............................................................14
3.2.1 Raster vs. Vector Data ...............................................................15
3.3 Data Description ......................................................................................17
3.3.1 Digital Elevation Models ...........................................................17
3.3.1.1 ? 90-meter DEM ..........................................................18
3.3.1.2 ? 30-meter DEM ..........................................................20
3.3.1.3 ? DEM Accuracy..........................................................21
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3.3.2 River Reach Files.......................................................................22
3.3.3 Water Right Locations ...............................................................24
3.3.4 Digital Raster Graphics..............................................................25
3.3.5 Precipitation Grids.....................................................................27
3.3.6 Curve Number Grids..................................................................28
3.4 Map Projections .......................................................................................28
3.5 Conclusion ...............................................................................................31
CHAPTER 4: PROCEDURE.............................................................................32
4.1 Introduction..............................................................................................32
4.2 Developing the Basin Control Points........................................................33
4.3 Developing the Basin Stream Network.....................................................38
4.3.1 Editing the Stream Network.......................................................39
4.3.2 Adding Streams to the Network .................................................45
4.4 Processing the DEM.................................................................................46
4.5 Computing the Watershed Parameters ......................................................50
4.5.1 Calculating Drainage Area.........................................................50
4.5.2 Calculating Average Curve Number and Precipitation ...............52
4.5.3 Reporting the Control Point Parameters .....................................53
4.6 Evaluating the Quality of Parameters........................................................55
4.7 Conclusion ...............................................................................................57
CHAPTER 5: CASE STUDY ?NUECES BASIN ................................................59
5.1 Introduction..............................................................................................59
5.2 Results from First Run .............................................................................59
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5.3 Change in Methodology ...........................................................................65
5.4 Results from Second Run .........................................................................67
5.5 Unresolved Errors ....................................................................................69
5.5.1 Short-Circuiting.........................................................................70
5.5.2 Quality Control Watersheds.......................................................71
5.6 Conclusion ...............................................................................................73
CHAPTER 6: CASE STUDY ?GUADALUPE &SAN ANTONIO BASINS...........74
6.1 Introduction..............................................................................................74
6.2 Results from First Run .............................................................................75
6.2.1 Guadalupe Results .....................................................................78
6.2.2 San Antonio Results...................................................................79
6.3 Changes in Methodology..........................................................................81
6.3.1 Processing DEM using Arc/Info ................................................82
6.3.2 Sub-dividing the Basin DEM .....................................................85
6.4 Results from Second Run .........................................................................89
6.4.1 Guadalupe Results .....................................................................90
6.4.2 San Antonio Results...................................................................91
6.5 Quality Control ........................................................................................92
6.6 Conclusion ...............................................................................................94
CHAPTER 7: CASE STUDY ?SAN JACINTO BASIN .......................................96
7.1 Introduction..............................................................................................96
7.2 Basin Processing ......................................................................................97
7.3 Streamlining the Methodology .................................................................98
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7.3.1 Snapping the Control Points to the Network...............................99
7.3.2 Generating the Table of Downstream Control Points................ 100
7.4 San Jacinto Basin Results....................................................................... 102
7.5 Quality Control ...................................................................................... 104
7.6 Conclusion ............................................................................................. 104
CHAPTER 8: RESULTS AND DISCUSSION.................................................... 106
8.1 Introduction............................................................................................ 106
8.2 Improved Results from the Use of 30-meter DEMs ................................ 106
8.3 Use of Buffered Streams ........................................................................ 109
8.4 Analysis of Degree of Terrain Relief ...................................................... 112
8.5 Quality Control ...................................................................................... 116
8.6 Conclusion ............................................................................................. 119
CHAPTER 9: CONCLUSIONS AND RECOMMENDATIONS............................ 120
APPENDIX A: NUECES BASIN RESULTS ..................................................... 124
A.1 Introduction ............................................................................... 125
APPENDIX B: GUADALUPE BASIN RESULTS.............................................. 139
B.1 Introduction ............................................................................... 140
APPENDIX C: SAN ANTONIO BASIN RESULTS ........................................... 161
C.1 Introduction ............................................................................... 162
APPENDIX D: SAN JACINTO BASIN RESULTS ............................................ 176
D.1 Introduction ............................................................................... 177
REFERENCES ............................................................................................... 189
VITA .......................................................................................................... 191
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LIST OF TABLES
Table 3.1: TSMS Albers map projection parameters........................................29
Table 3.2: UTM map projection parameters ....................................................30
Table 4.1: Contractor identified control points for San Jacinto Basin...............36
Table 4.2: Basin numbers................................................................................38
Table 4.3: Drainage area comparison for Nueces basin control points .............56
Table 5.1: Comparison of CRWR reported values and established drainage
areas. ..............................................................................................62
Table 5.2: Comparison of drainage areas from first and second runs. ..............67
Table 5.3: Nueces Basin incremental areas......................................................69
Table 6.1: Comparison of CRWR reported values and established drainage
areas...............................................................................................78
Table 6.2: Comparison of CRWR reported values and established drainage
areas. ..............................................................................................80
Table 6.3: Comparison of results from second run to established
USGS/HDR values .........................................................................90
Table 6.4: Comparison of results from second run to established drainage
areas. ..............................................................................................91
Table 6.5: Comparison of computer and hand-delineated watersheds ..............93
Table 7.1: Comparison of CRWR and USGS values for San Jacinto gages.... 102
Table 8.1: Statistical summary of % difference in results for 90-meter
and 30-meter data. ........................................................................ 108
Table 8.2: Statistical summary of difference in results for burning and not
burning streams. ........................................................................... 112
Table 8.3: Representative slopes of the 4 basins within the study area........... 115
x
LIST OF FIGURES
Figure 1.1: Image of Texas river basins.............................................................5
Figure 2.1: Burning streams into grids of different scales ................................11
Figure 3.1: Comparison of features in raster and vector format........................16
Figure 3.2: Sample representation of a DEM...................................................18
Figure 3.3: Image of DEM elevations overlain on topographic contours..........19
Figure 3.4: River reach file for the San Jacinto basin.......................................22
Figure 3.5: San Jacinto water rights overlain on RF3.......................................25
Figure 3.6: Sample USGS digital raster graphic ..............................................26
Figure 3.7: PRISM average annual rainfall grid for Texas...............................27
Figure 4.1: Project flow chart..........................................................................32
Figure 4.2: Master water right with diversions ................................................34
Figure 4.3: Query function for eliminating unwanted features in RF3..............40
Figure 4.4: RF3 before editing ........................................................................41
Figure 4.5: Disconnect in RF3 after removing open water features..................41
Figure 4.6: Reservoir transport path (red) from USGS centerline file ..............42
Figure 4.7: Braided stream section with highlighted reaches to be deleted.......43
Figure 4.8: Water right within stream loop......................................................44
Figure 4.9: Manually digitized streams added to original RF3 .........................46
Figure 4.10: San Jacinto basin DEM with basin boundary...............................47
Figure 4.11: Flow direction grid of San Jacinto basin ......................................49
Figure 4.12: Flow accumulation grid of San Jacinto basin ...............................49
Figure 4.13: An incorrectly located control point ............................................51
Figure 4.14: Excerpt of parameter attribute table.............................................54
Figure 5.1: Nueces basin layout.......................................................................60
Figure 5.2: CRWR boundary overlain on established boundary.......................65
Figure 5.3: New watershed delineation overlain on basin boundary.................66
Figure 5.4: Lower portion of Nueces basin with CP30 and CP31 highlighted. . 68
Figure 5.5: Stream network overlain on burned DEM......................................70
Figure 5.6: Hand-delineated watershed for quality control...............................72
Figure 6.1: Layout of Guadalupe River basin ..................................................75
Figure 6.2: Layout of San Antonio River basin................................................76
Figure 6.3: Diagram of sub-division process ...................................................86
Figure 6.4: Comparison of 90m and 30m data images .....................................89
Figure 7.1: San Jacinto basin layout ................................................................97
Figure 7.2: Comparison of DEM-derived stream network and single-line
network ........................................................................................99
Figure 7.3: Control point connectivity diagram ............................................. 101
Figure 7.4: CP8076000 watershed diagram with circles denoting erratic
features....................................................................................... 103
xi
Figure 8.1: Results from the use of 30m and 90m data in the San Antonio
and Guadalupe basins ................................................................. 107
Figure 8.2: San Jacinto basin without and with buffered streams. .................. 110
Figure 8.3: Results from burning and not burning streams in the Nueces
and San Antonio ......................................................................... 111
Figure 8.4: Effect of slope on absolute % difference in drainage area (90m).. 113
Figure 8.5: Effect of slope on absolute % difference in drainage areas (30m).114
Figure 8.6: Analysis of slope as a function of distance from coast. ................ 116
Figure 8.7: Plot of results from 90m DEM for small watersheds.................... 117
Figure 8.8: Plot of results from 30m DEM for small watersheds.................... 118
1
CHAPTER 1: INTRODUCTION
1.1 BACKGROUND
The vast area covered by the State of Texas can become a problem when
studying water resource issues. For example, the eastern portions of Texas
receive an abundant amount of rain, while the western portions are virtually dry.
Even during normal rainfall periods, some areas lack sufficient water supplies to
meet all demands. This lack of water is magnified in periods of drought, to the
extent that essential needs may be threatened. These issues alone require
extensive planning for current and future water demands. If we also consider the
effects of population growth, as well as new and emerging environmental issues,
the need for complex management tools to identify, assess, and resolve these
water resource issues becomes evident. The State of Texas is a leader in the
acquisition, maintenance, and use of planning tools, such as water availability
models (TNRCC, 1998).
Water availability models are computer programs that calculate the
amount of water in a river basin, using both hydrologic principles and actual
measurements taken at stream gages. During the 1970s and 1980s, the
predecessor agencies of the Texas Natural Resource Conservation Commission
(TNRCC) developed water availability models for 8 of the 23 river basins within
the State. These models were basin-specific and are now considered obsolete.
These older models lack the design capacity to handle the data inputs and
2
calculations needed for full water resource management in Texas, and their data
reside in obsolete mainframe computer systems (TNRCC, 1998).
When a severe drought hit the Texas area in the summer of 1996, water
resource management issues were brought to the forefront. By August, many
lakes were far below their normal levels, while streamflows in rivers and creeks
ranged from 11 to 50 percent of average historic flows. Disputes arose over water
use as a result of uncertainty about the reliability of Texas? existing water supplies
and the ability to develop new supplies (TNRCC, 1998).
In January of 1997, the Texas Legislature responded by drafting Senate
Bill 1. This legislation addressed a wide range of water management issues,
including the provision of funds to the TNRCC to begin development of water
availability models for 22 of the state?s 23 river basins. The new models form a
complete modeling system for the state: The Texas Water Availability Modeling
System (WAM). The components of the WAM system include a database of
water rights, water uses, streamflows, and other data; Geographic Information
System (GIS) tools to analyze drainage basin characteristics; and the water
availability model (TNRCC, 1998).
Much of the cost and time-consuming work in developing a water
availability modeling system lies in the calculation of the input data. This process
includes estimating ?naturalized? streamflows and accounting for water demands.
?Naturalized? streamflows refers to the water that would historically flow in a
river without human impact, while water rights refer to locations where legal
permits exist to draw water from rivers and streams. Once ?naturalized?
3
streamflows are calculated, all permitted water withdrawals for existing water
rights are subtracted in priority order to determine how much water remains for
permitting and other purposes (TNRCC, 1998). The priority system is established
on a seniority basis, which means a senior water right is entitled to its allotment of
water before any water right junior to it.
In part, this thesis presents an approach for calculating the input data
required for the Texas Water Availability Model. The input data includes the
drainage area, average curve number, average precipitation and next downstream
point for each water right in the study area. With 22 river basins and over 8000
water rights in the state, hand calculations are not at all feasible. However, GIS
offers an ideal environment for this type of work. GIS allows for the
manipulation of large amounts of data and provides a format to study the data in
large-scale situations, such as the entire state of Texas.
A basic methodology for calculating the input data had already been
established by a previous researcher on the WAM project, Brad Hudgens (1999).
Therefore, in addition to presenting the methodology, this thesis also includes
case studies of 4 basins completed over the last year: Nueces, Guadalupe, San
Antonio, and San Jacinto. The purpose of these case studies is to analyze the
effects of changes in the methodology on the accuracy of the output watershed
parameters.
4
1.2 OBJECTIVES
There were four primary objectives of this research:
1. Acquire and generate GIS data layers for all 4 basins in the study
area. These layers include basin boundaries, river networks, digital
elevation models (DEMs), digital raster graphic maps (DRGs),
water right locations, stream gage locations, Soil Conservation
Service (SCS) curve number grids and mean annual precipitation
grids.
2. Use ArcView GIS and Arc/Info GIS utilities to develop a spatial
water rights database for each basin. These databases include
watershed parameters for each water right and stream gage
location, called ?control point locations.? The following are the
watershed parameters needed for each control point: (1) delineated
upstream drainage area, (2) average SCS curve number for that
drainage area, (3) mean annual precipitation for that drainage area,
(4) downstream flowlength along the river to the basin outlet, and
(5) next downstream control point.
3. Analyze the results of each basin on a case-by-case basis. Changes
in the methodology were made throughout the process as new data
became available and problems where encountered. The case
studies focus on the effects that these changes had on the final
results.
5
4. Synthesize the results from each case study in order to assess the
accuracy of the results with respect to data resolution (90m vs 30m
digital elevation models) and degree of terrain relief (slope).
1.3 STUDY AREA
As per Senate Bill 1, water availability models were developed for six of
states major river basins in Texas by December 31, 1999. Brad Hudgens (1999)
developed the parameters for the first 2 basins in the study (Sulphur and Neches),
while this research focused on the final 4 basins: Nueces, Guadalupe, San
Antonio, and San Jacinto. Figure 1.1 is an image showing the location of the
basins studied in this research.
Figure 1.1: Image of Texas river basins. Highlighted, from left to right, are the Nueces, San
Antonio, Guadalupe, and San Jacinto
6
1.4 METHODS
Achieving these objectives required research into what data sets are
available and which ones best suit the needs of the project. The main sources of
data acquisition were the United States Geological Survey (USGS), the
Environmental Protection Agency (EPA), and TNRCC, all of which provide very
current GIS data files that are essential for accurate results. Most of the files were
obtained by downloading them from the websites of the above agencies.
Once all the files for a basin were downloaded, the next step was to edit
the data in ArcView and Arc/Info. For example, the river networks obtained from
the EPA contained many unwanted features, such as lakes and braided streams.
For the purposes of this project, only a single-line stream network (i.e. a single
path for every stream from top to bottom) was needed. Therefore, these unwanted
features had to be located and deleted before continuing with the processing.
Once the streams were edited, the water rights were located along the stream
network.
Another essential piece of the processing was the use of the Center for
Water Resources Pre-Processing tools (CRWR Pre-pro). As an extension of
ArcView, these tools served to create data layers from the original DEM. The
single-line stream network was combined with the DEM to create a flow
accumulation grid. Using this grid, along with the water rights that had
previously been located, the value of the drainage area was found for each water
right location. A similar process was used to find the average SCS curve number
and the mean annual precipitation for these points.
7
The final parameters in the database were found through the use of tools
developed at CRWR. For example, a script was written that snapped the water
right points to the stream network. Once the points were snapped, the script was
then able to follow the single-line network downstream until it located the next
point. The downstream flowlength was found in a similar manner (i.e. tracing a
path downstream).
1.5 OUTLINE
The research detailed in this thesis not only shows an approach for
calculating watershed parameters for a number of locations, but also provides an
analysis of the accuracy of the results for each of the four basins studied. This
thesis is divided into nine chapters. Following the introduction, a comprehensive
literature review was performed, which resides in Chapter 2. The third chapter
contains background information on GIS and GIS tools, as well as information on
the data files that were used in the research. Chapter 4 provides a brief
explanation of the methods used to calculate the required parameters from the
acquired data sets. A more detailed description of these methods can be found in
Brad Hudgens (1999). Chapters 5, 6, and 7 contain the case studies of the four
basins studies (Nueces in Ch. 5, Guadalupe/San Antonio in Ch. 6, and San Jacinto
in Ch. 7). Chapter 8 presents a synthesis of the case study results, with a
discussion of the effects of each methodology change. The final chapter presents
the conclusions and recommendations for further research in this area. The
Appendix contains additional information on the results of this research.
8
CHAPTER 2: LITERATURE REVIEW
2.1 INTRODUCTION
Before this research was undertaken, an extensive literature review was
performed to establish the state of knowledge in the area of terrain analysis.
Because most of the advances in this area occurred in the last 15 years, ample
literature exists.
2.2 TERRAIN ANALYSIS
Original terrain analysis studies simply consisted of the visual
interpretation of maps and aerial photographs. However, manual interpretation of
such products and the subsequent measurement or digitization of topologic
properties was quite tedious for any but the smallest data sets (Band, 1986). With
over 8000 water rights to be concerned with in Texas, automated methods using
geospatial data had to be utilized. The growing availability of digital elevation
models, produced by the USGS, facilitated the applicability of automated
techniques to a variety of hydrologic research (Band, 1986).
In the mid 1980?s, several methods were developed to extract hydrologic
information automatically from DEMs. Before using the DEM, however, it was
recommended that the data be processed through a 3-step conditioning phase. As
Jenson (1991) showed, depressions in the DEM were first ?filled? by raising the
values of cells in depressions to the value of the depression?s spill point. Next,
the computation of the flow direction for each cell in the depressionless DEM was
performed. The direction water will flow out of each cell is encoded to
9
correspond to the orientation of one of the eight cells that surround the cell. In
flat areas, the flow directions are iteratively calculated so that the flow path
traverses the flat area and continues downhill to one of the flat area?s spill points.
This process of defining flow direction performs well on land surfaces
characterized by well-established drainage patterns. The third conditioning step is
the computation of the flow accumulation value for each cell. This is the count
for each cell of how many upstream cells would contribute drainage to it based on
their flow directions. After the conditioning phase, the datasets can be further
processed to delineate watersheds.
Although Jenson states this process to be accurate in well-defined areas,
problems can arise in areas of low relief. Research by Saunders (1996) confirmed
the accuracy of the method in the topologically diverse portion of the San
Antonio-Nueces river basin away from the coast, showing close agreement with
the generally accepted USGS 1:100,000 scale stream network and USGS
Hydrologic Cataloging Units. However, in the near-coast portions of the basin,
where slopes were generally flat, drainage paths were distorted and tended to
?short-circuit? the actual known locations of streams. Jenson?s method interprets
watersheds from the digital terrain information. But, depending on the DEM
resolution, valuable stream information can be missed when defined by a DEM
alone.
Kirkby (1993) explains the importance of the digital stream network.
Since the channel network is the focus for the interacting processes that carry
water out of the drainage basin, it is ultimately responsible for shaping the
10
landscape. Thus, the network is the framework to tie together and structure the
distribution of all watershed information required for simulation of a broader
range of hydrological processes.
Maidment (1996) suggests a variation to the DEM processing method.
Since critical errors can occur when only using the DEM to define the drainage
network, it is suggested that the DEM grid be used in conjunction with a mapped
representation of the stream network, such as the EPA?s River Reach file. The
mapped streams can be converted into a grid and ?burned in? to the DEM by
artificially raising the elevation of the off-stream cells. This technique requires
editing the stream network to eliminate any artifacts that would confuse the
delineation process, such as loops and gaps. Although some distortion of
watershed boundaries still occur, the burning in method has the great advantage of
the DEM delineated streams matching the mapped streams exactly. Again, it
follows the theory that it is the stream network that is really the critical item in
landscape delineation. The ?burn in? process technique is especially useful in
coastal zones with very flat terrain and other locations where drainage is directed
through constructed channels.
Other issues arise when combining vector data layers with raster DEM
layers. Not all vector and raster data layers have sufficiently compatible map
scales for the integration process. For example, Saunders (1999) points out that a
vector data layer should never be burned into a raster data layer of coarser
resolution. Figure 2.1 shows the problem of burning streams into a DEM when
the two layers are not of similar scales.
11
Figure 2.1: Burning streams into grids of different scales (Saunders, 1999)
Figure2.1ashowsafinescalenetworksuperimposedonbothacoarseand
a fine scaled DEM. The conversion of the vector stream network into a raster
network is shown in Figure 2.1b. Note that a grid cell is created where any
portion of the vector network is located. Figure 2.1c shows the final, digital
stream network, which reduces the flow network to strings of single cells. Also in
12
Figure 2.1c, the original vector network is superimposed on the raster network to
show that integration of the fine scale layer into the coarse scale DEM results in
an oversimplification of the stream network (Saunders, 1999).
Maidment (1996) suggests that DEMs of 30m (1:24,000 scale) and 90m
(1:250,000 scale) cell size should be used for regional studies the size of Texas.
However, at the inception of this project, only 90m data existed for the entire
state. Therefore, previous work on areas of this size relied heavily on the use of
1:250,000 scale DEM data. Since nationwide, vector stream data only exists at
1:100,000 scale, the issue of conflicting scale was an issue in the previous work
on the Water Availability Modeling project by Hudgens (1999). Short-circuiting
of the stream network occurred when vector streams were located closely
together. Thus, results were not always accurate. Hudgens (1999) also showed
the inability of 1:250,000 scale data to accurately calculate the area of small
watersheds. Hudgens (1999) explained the necessity to quality control all
watersheds with a flow accumulation of less than 1000 cells.
This research makes use of the relatively recent availability of the
National Elevation Dataset, a 1:24,000 scale DEM for the entire State of Texas.
At this time, no previous studies can be found evaluating drainage areas produced
from 1:24,000 scale data for an area the size of a major river basin.
2.3 CONCLUSION
Terrain analysis has progressed considerably from the days of manual
delineation. Although manual delineation may still be required to define drainage
in problematic areas, automated methods have been proven to be both accurate
13
and efficient. Aside from the ample amount of literature on the results of
automated delineation processes, this research will contribute an analysis of the
results obtained from the incorporation of newly created, 30m data. Comparisons
will be made between results from 90m data and 30m data on the same area to
evaluate the accuracy and efficiency of the standard methodology. Also, an
assessment of the level of quality control needed when using 30m data will be
made (i.e. the validity of the 1000 cell flow accumulation threshold for small
watersheds).
14
CHAPTER 3: SYSTEM AND DATA DESCRIPTION
3.1 INTRODUCTION
Because GIS and digital data were valuable tools in the work performed
for this thesis, it is appropriate to discuss the features and advantages of GIS, as
well as describe the data sets used. This chapter will cover both tasks.
3.2 GEOGRAPHIC INFORMATION SYSTEMS
Before entering into a description of the data used in this research, it is
first important to gain an understanding of GIS and the tools used to manipulate
the data. Use of GIS has grown dramatically over the past decade, and it is now
commonplace for business, governmental, and academic institutions to use GIS
for many diverse applications. Consequently, many definitions of GIS have
developed (ESRI, 1997). However, perhaps the most concise definition of GIS is
that offered by the Association for Geographic Information: ?A system for
capturing, storing, checking, integrating, manipulating, analyzing and displaying
data which are spatially referenced to the earth.?
From this definition, we see that GIS is not simply a computer system for
making maps, as most people assume. A GIS is an analytical tool. The major
advantage of such a tool is that it allows you to identify the spatial relationships
among map features (ESRI, 1997). This ability was fundamental in the choice of
GIS for the Water Availability Modeling research project. By overlaying maps of
water rights, river networks and river basins, relationships between features can
be found. For example, we can know which water right fell on which river reach
15
and in which basin, and which water rights are upstream and downstream of the
current one. This process has previously been done by manual interpretation of
paper maps, often a cumbersome procedure.
Another important feature of GIS is the linking of spatial data with
geographic information about a particular feature on a map. Each feature in a GIS
map is linked to a set of attributes that is stored in a database (ESRI, 1997).
Therefore, a person can query a feature on a map and retrieve a wealth of
information about the map feature. The programs used to perform such queries
and analyses in this study were ARC/INFO GIS and ArcView GIS, both
developed by the Environmental Systems Research Institute (ESRI).
ARC/INFO and ArcView differ in a couple of very distinct ways. For
example, ARC/INFO uses a command language that functions similarly to the
way a computer?s operating system works: commands are entered at a prompt
before different tasks (ESRI, 1997). However, ArcView is a much more visual
medium for working with maps. Based totally in a Windows operating system,
operations and commands are performed mainly through menu options and user-
created scripts (or programs), rather than built-in functions.
3.2.1 Raster vs. Vector Data
Date format is another important issue when discussing GIS. Data in GIS
can be represented in either a raster or vector format. A raster-based system
displays, locates, and stores graphical data by using a grid of cells. Each grid cell
is represented by a unique reference coordinate at either the corner or centroid of
16
the cell. In addition, each cell has discrete attribute data assigned to it (Foote,
1996). An example of such data is a Digital Elevation Model.
In contrast, vector based systems display graphical data as points, lines or
areas with attributes. Cartesian coordinates (i.e., x and y) and computational
algorithms of the coordinates define points in a vector system. For example, lines
are represented as a series of points, while areas are stored as a series of points
with the beginning and end points at the same node, so that the shape is closed.
The graphical output is very similar to hand-drawn maps (Foote, 1996). An
example of vector data is the EPA?s river reach file. The following figure is a
comparison of vector and raster data.
Figure 3.1: Comparison of features in raster and vector format (Maidment, 1998)
Following this brief description of GIS, the next step is to take a look at
the data that were used in building the water rights database.
17
3.3 DATA DESCRIPTION
Many different types of data are required for a project that will eventually
provide information on the entire state of Texas. Therefore, it is important to take
a look at each data set in detail. The following is a list of the data sets to be
discussed in this section:
? Digital Elevation Models
? Environmental Protection Agency River Reach Files (Version 3.0)
? Water Right Locations
? Digital Raster Graphics
? Precipitation Grids
? Curve Number Grids
3.3.1 Digital Elevation Models
One of the most important data sets needed for drainage area calculations
is an accurate representation of the land surface. In a GIS framework, a Digital
Elevation Model (DEM) contains such information. A DEM consists of a
sampled array of elevations for ground positions that are normally at regularly
spaced intervals, as shown in Figure 2.2.
18
Figure 3.2: Sample representation of a DEM (Maidment, 1998)
In the early stages of this project, the best available data sets were 90-
meter DEMs (3 by 3-arc second spacing), which contained elevation values at
approximately 90-meter intervals (USGS, 1996). However, during the course of
the work, the National Elevation Dataset (NED) was made available for the state
of Texas. The NED files (or 30-meter DEMs) are DEMs with grid cells of 1 by 1-
arc-second spacing or elevation values at 30-meter intervals. The next section
discusses these two data sets in detail.
3.3.1.1 - 90-meter DEM
The 90m DEM (often called the 3 arc-second DEM) provides coverage in
1- by 1-degree blocks for all the contiguous United States. The majority of the 3
arc-second DEMs were produced by the Defense Mapping Agency (DMA) from
cartographic and photographic sources. However, the final product is distributed
by the USGS EROS Data Center (USGS, 1996).
19
Elevation data from cartographic sources are collected from USGS 7.5-
minute through 1-degree maps. Topographic features such as contours and
ridgelines are first digitized and then processed into the required matrix form and
interval spacing (USGS, 1996). Figure 3.3 shows an example of DEM elevation
values in comparison to contour lines on a topographic map.
Figure 3.3: Image of DEM elevations overlain on topographic contours (Maidment, 1998)
Manual and automated correlation techniques are used to collect elevation
data from photographic sources. First, the elevations along a profile are collected
at 80 to 100 percent of the eventual point spacing. Then, the raw elevations are
weighted with additional information during the interpolation process in which
final elevations are determined for the required matrix form and interval spacing
(USGS, 1996).
20
The elevation data for the 3 arc-second DEM are referenced horizontally
on the geographic (latitude/longitude) coordinate system of the World Geodetic
System 1972 (WGS 72) and are referenced vertically in meters relative to the
National Geodetic Vertical Datum of 1929 (NGVD 29). The data are
approximately equivalent to that which can be derived from contour information
represented on 1:250,000 scale maps (USGS, 1996).
Each file contains 1201 rows and columns or approximately 1.4 million
cells and takes 6.91 MB of memory with elevations in floating point meters. The
river basins covered by this study require 4-6 one-degree blocks to cover them.
Typical grid sizes for the river basins were 10 million cells.
3.3.1.2 - 30-meter DEM
The NED is a new raster product assembled by the USGS and has a
resolution of 1 arc-second (approximately 30 meters) for the conterminous United
States. The NED is designed to provide national elevation data in a seamless
form with a consistent datum, elevation unit, and projection (USGS, 1999).
Building a seamless elevation database involved a complex system for
performing the conversion and transformation of over 50,000 DEM files. Once
all the DEMs in the National Digital Cartographic Database were identified, the
system accomplished the following: filtered production artifacts, computed datum
conversions, appended individual DEM files, computed coordinate
transformations, resampled data; merged the various sources, and performed edge
matching between each separate DEM file. As with the 90-meter DEM, the files
were stored in 1-degree by 1-degree blocks (USGS, 1999). Each file in this
21
dataset contains 3600 rows and columns or approximately 12.9 million cells and
takes 52.8 MB of memory with elevations in floating point meters. Typical 30-
meter grid sizes for the river basins were 60 million cells.
Unlike the previous 30-meter DEM sources, the final NED product has
universal data characteristics. In the NED assembly process, the elevation values
were converted to decimal meters as a consistent unit of measure; North
American Datum 1983 was consistently used as the horizontal datum; and all the
data were recast into a geographic projection, whereas the earlier 30-meter DEMs
were in UTM projection (USGS, 1999).
3.3.1.3 - DEM Accuracy
The main factors that determine the accuracy of a DEM are the source
resolution and the spatial resolution (or grid spacing) of the data profiles. Since a
dependency exists between the scale of the source materials and the level of grid
refinement possible, the source resolution determines the level of content that may
be extracted during digitization. Within a standard DEM, most terrain features
are generalized by being reduced to grid nodes spaced at regular intersections in
the horizontal plane. This generalization reduces the ability of the DEM to
represent positions of specific features smaller than the internal spacing of the
nodes and results in a ?smoothing? of the surface during gridding (USGS, 1996).
Therefore, the assumption is that higher resolution data (i.e. smaller grid spacing)
more accurately represents the drainage features of the terrain and results in more
accurate watershed delineations.
22
3.3.2 River Reach Files
In order to perform any study of this kind, there is a need for some
representation of the rivers and streams that dominate the water flow in the area.
For its accuracy and breadth of information, the Environmental Protection
Agency?s River Reach File Version 3, known as RF3, was used as the stream
network representation. RF3 is a national hydrologic database that interconnects
and uniquely identifies the 3.2 million stream segments that comprise the
country?s surface water drainage system (Dewald, 1994). These vector data sets
contain digital images of many surface water features, including rivers, streams,
lakes, reservoirs and canals. Figure 3.4 shows the RF3 file for the San Jacinto
River Basin, located on the Gulf Coast of Texas.
Figure 3.4: River reach file for the San Jacinto basin
23
The RF3 production process was two-fold: 1) compilation of spatial and
attribute data from existing sources; 2) assignment of reach codes to the segments
in the network. The compilation part of RF3 production involved the
combination of the following: 1) relevant portions of the first two versions of the
reach files (RF1 and RF2); 2) the USGS Geographic Names Information system
database; 3) the 1988 USGS 1:100,000 scale hydrography dataset. The second
part of RF3 production involved the assignment of a unique reach code to each
segment contained within the USGS hydrography. The reach codes contained
within RF3 uniquely identify, by 8-digit Hydrologic Unit Codes (HUC), the
individual components of the Nation?s rivers and lakes. The reach code
assignment process allowed for the determination of the upstream/downstream
relationship of each river reach. Thus, by piecing together all the reaches in the
proper order, a national hydrologic network was formed (Dewald, 1994).
During this research, USGS was working on another set of river reach
files called the National Hydrography Dataset (NHD). The NHD is the
culmination of a cooperative effort between the EPA and the USGS. It combines
elements of USGS digital line graph (DLG) hydrography files and the USEPA
Reach File (RF3). An important addition to the NHD is the inclusion of flow
direction and centerline representations through surface water bodies (USGS,
1999). Although the entire dataset was not available for use in the basins studied
in this research, the NHD centerlines were utilized in the stream editing process
discussed in Chapter 4.
24
The value of RF3 to the Water Availability Modeling project was clear.
The extensive coverage of the river reach files provided an additional source of
information for defining the drainage patterns of the landscape. Also, by using a
nationally consistent hydrologic network, permit writers (namely TNRCC) had
the ability to ?navigate? upstream or downstream when assessing the effect of one
water right on another in the network.
3.3.3 Water Right Locations
Along with the quantification of naturalized flows, the second part of the
Water Availability Modeling system is the calculation of water that is drawn out
of the system by landowners. Since all water in rivers, streams, lakes, etc.
belongs to the state, a person must acquire the ?right? to withdraw water from the
natural system. This, quite simply, defines a water right. Therefore, compiling
the locations of all existing water rights became a task in this research.
All permits for water rights must be requested from the TNRCC. Once
requested, the TNRCC determines whether water is available, and if so, grants the
permit. Once granted, the water right is located on a paper map and given a
spatial coordinate (latitude/longitude). From these records, a GIS point coverage
was created to represent all the water right locations on a river or stream in the
surface water network, as shown in Figure 3.5. The process of creating the point
coverage is discussed in Chapter 4.
25
Figure 3.5: San Jacinto water rights overlain on RF3
3.3.4 Digital Raster Graphics
Although the RF3 is considered to be a good representation of the river
network, errors in the files do exist. However, without any other information,
these errors can go unnoticed. Therefore, a need existed for another source of
terrain information to double-check the RF3 files.
A digital raster graphic (DRG) is a scanned image of a USGS topographic
map. This image is georeferenced to the earth and can be used to collect, review,
and revise other digital data, especially digital line features. In addition, the maps
are produced at the 1:24,000 scale (as compared to the 1:100,000 scale RF3),
26
which gives a more detailed representation of the land surface (USGS, 1999). A
sample image is shown in Figure 3.6.
Figure 3.6: Sample USGS digital raster graphic (USGS, 1999)
Once the USGS topographic paper map is scanned, the digital image is
georeferenced to the true ground coordinates and projected to the Universal
27
Transverse Mercator (UTM) for projection consistency. The original datum
(normally North American Datum 1927) is preserved in the DRG (USGS, 1999).
3.3.5 Precipitation Grids
In order to calculate how much water is available for a given water right,
information about mean annual precipitation in the drainage area is needed. For
the purposes of this research, a gridded representation of rainfall was the most
useful. Therefore, the Oregon State PRISM climate grids (which are GIS-
compatible) were chosen as the best source of climatic information. Below is an
image of rainfall variation across the state of Texas.
Figure 3.7: PRISM average annual rainfall grid for Texas
28
PRISM (Parameter-elevation Regressions on Independent Slopes Model)
is an analytical model that uses point data and a DEM to generate gridded
estimates of monthly and yearly climatic parameters. More importantly, PRISM
has been used extensively to map precipitation across the entire United States in a
spatially representative and physically meaningful way. The resulting
precipitation layer has physically realistic detail and has a national spatial extent
(Daly, 1996).
3.3.6 Curve Number Grids
Finally, the last data set needed was the Soil Conservation Service Curve
Number grid. A curve number is a value (ranging from 0-100) that represents the
ability of the land surface to capture water. A low curve number means that water
easily infiltrates into the soil, leaving less for run-off. A high curve number
means the water is not captured by the land surface, but instead turns into run-off.
The Blacklands Research Center in Temple, Texas provided the Curve
Number grid that was used in this research. Using the USDA/NRCS STATSGO
soil coverage with the USGS LULC coverage, the Blacklands Research Center
generated a 250-m resolution grid by combining the soil and land values into
curve numbers using the 1972 SCS Engineering Hydrology Handbook as a
reference (Hudgens, 1999).
3.4 MAP PROJECTIONS
Choosing the proper map projection to work with all the data files was a
core issue at the outset of this project. Maps, of course, are 2-D representations of
3-D surfaces. The process of projecting curved surfaces onto flat maps inevitably
29
distorts one or more properties of the land features ? shape, area, distance, etc.
Therefore, a need existed not only for a consistent map projection to work with
the files, but also a map projection that would preserve area when performing
drainage area calculations.
Fortunately, Texas had already defined a consistent map projection for use
throughout the state: Texas State Mapping System (TSMS). Since TSMS Albers
preserves true earth surface area for polygons, it was chosen as the coordinate
system for all project deliverables. Table 3.1 shows the projection attributes.
Parameters TSMS Albers
Projection Albers
Datum NAD 83
Spheroid GRS1980
Units Meters
Standard Parallel 1 27 25 00
Standard Parallel 2 34 55 00
Central Meridian -100 0 00
Reference Latitude 31 10 00
False Easting 1000000
False Northing 1000000
Table 3.1: TSMS Albers map projection parameters
30
However, one of the main files used in the stream editing procedure was
the digital raster graphics. These files were retrieved from TNRIS in the
Universal Transverse Mercator (UTM) projection, which consists of a sequence
of 6-degree zones covering the globe. Three of these zones (13, 14, and 15) cover
the State of Texas. Zones 14 and 15 cover the 4 basins studied in this research.
Originally, an attempt was made to project the DRG files into the TSMS albers
projection so that they would overlay with the remainder of the files.
Unfortunately, the DRG files were far too large and very time consuming to
project. So, during the editing process, the stream network and point coverages
had to be projected into UTM to perform the required edits before being projected
back to TSMS albers for the final processing. Table 3.2 shows the UTM
projection parameters.
Parameters UTM
Projection UTM
Zone 14 or 15
Datum NAD 27
Spheroid Clarke 1866
Units Meters
Table 3.2: UTM map projection parameters
31
3.5 CONCLUSION
Many different data sets were required for this research. The next chapter
describes the steps taken to compute the watershed parameters for all the water
right locations within the study basins.
32
CHAPTER 4: PROCEDURE
4.1 INTRODUCTION
At the outset of this research, a general procedure for developing a spatial
water rights database had already been established by Hudgens (1999). This
chapter contains an overview of this procedure, which leads into a description of
the changes made to improve the methodology and results in the case studies to
follow. Figure 4.1 is a simple flow chart of the project tasks discussed.
Figure 4.1: Project flow chart.
33
Chapter 4 is divided into 5 sections. The first section discusses the
development of the control point coverages to be used in the modeling. Section 2
describes the processes used to develop the basin stream network. The third
section details the methods used to process the DEM in preparation for drainage
area calculations. Then, section 4 shows how all the watershed properties are
calculated and compiled. Finally, the fifth section explains the quality control
techniques used to ensure accurate results. This chapter is simply an overview of
the database development procedures. For a detailed, step-by-step description of
the database development, see Hudgens (1999) at
http://www.crwr.utexas.edu/crwr/reports/rpt99_4/rpt99_4.html.
4.2 DEVELOPING THE BASIN CONTROL POINTS
One of the key elements in this research was obtaining accurate locations
of all the model control points for each of the river basins. The model control
points consist mainly of water rights, diversion locations, stream gages, and return
flow locations. Since the control points were developed by various parties (both
TNRCC and the basin contractor), the first task was to compile a common set of
files for each party to use. Thus, CRWR provided both TNRCC and the basin
contractor with a location review cd-rom that contained all of the working files
needed to establish the control point locations. The following is a list of files
contained on the cd-rom:
34
? Master water rights file
? Stream gage locations
? River reach file (RF3)
? Basin coverage
? County coverage
? 7.5-minute quadrangle mesh
? DRGs
The master water rights file consists of a GIS coverage of all the water
right locations in the basin. However, each water right may have several
diversion locations associated with it. These diversions consist of return flow
locations, on-channel reservoirs and off-channel reservoirs. Figure 4.2 shows an
example of a master water right and its associated diversions.
Figure 4.2: Master water right with diversions
35
Since CRWR does not have access to the water right permits defining
these diversions, it becomes the task of the TNRCC to locate all of these points.
Therefore, TNRCC uses the location review cd-rom to check the water right
locations against their records, and then edits the water right coverage
accordingly. Once the editing process is completed, the new water rights
coverage is returned to CRWR for further processing. This step will be discussed
later.
The basin contractor has the ultimate responsibility of determining which
points will be modeled. Thus, once the water right locations are set, the
contractor delivers the additional points needed for the modeling. These points
usually consist of known flow locations, such as USGS stream gages. Other
points included throughout the project were additional return flow locations and
locations along aquifer recharge zones. Unlike the coverages received from
TNRCC, these points usually were delivered in spreadsheet format (Table 4.1).
36
Gage # Lat Long Area (mi
2
)
8067650 30?20'31" 095?32'34" 451
8068000 30?14'40" 095?27'25" 828
8068500 30?06'37" 095?26'10" 409
8068740 29?57'32" 095?43'03" 131
8069000 30?02'08" 095?25'43" 285
8069500 30?01'37" 095?15'28" 1741
8070000 30?20'11" 095?06'14" 325
8070500 30?15'34" 095?18'08" 105
8071000 30?13'57" 095?10'05" 117
8071500 29?59'40" 095?08'00" 2800
8073500 29?45'42" 095?36'20" 293
8074000 29?45'36" 095?24'30" N/A
8074500 29?46'30" 095?23'49" 86.3
8075000 29?41'49" 095?24'43" 94.9
8075500 29?40'27" 095?17'21" 63
8076000 29?55'05" 095?18'24" 68.7
Table 4.1: Contractor identified control points for San Jacinto Basin
As shown in Table 4.1, each gage was located by a latitude and longitude.
Using these locations, a point coverage was generated in Arc/Info that was then
overlaid on the basin files to check for proper location. In most cases, this
37
method was sufficient to properly determine the exact location of the point.
However, in some instances, the points fell in areas without streams or even
outside the basin. Also, if a point fell near a junction, it was essential to know
exactly which tributary the point should be on to ensure that proper parameters
are calculated later. Thus, the DRGs on the location review cd-rom became a
valuable tool for both CRWR and the basin contractor in the communication of
these problems. Often the contractor would send a photocopy of the
corresponding USGS paper map with the exact location of the point drawn on the
map. With this in hand, CRWR was able to place the point properly.
Another task in developing the basin control points was the establishment
of a unique identifier for each point. Originally, each water right was identified
by its permit number, which was usually a 5-digit integer. However, with the
addition of diversion points associated with these water rights, a new
identification system had to be developed. With the assistance of TNRCC, the
following scheme was used: BBTWWWWWDDD where,
? T = type (1 or 6)
? BB = basin number (01 to 23)
? WWWWW = water right permit number
? DDD = diversion point number
o 001 ? 099 = diversion point
o 101 ? 199 = upstream limit of segment
o 201 ? 299 = downstream limit of segment
o 301 ? 399 = on-channel reservoir
o 401 ? 499 = off-channel reservoir
o 501 ? 599 = return flow
38
The T represents the type of water right, with the 1 representing
adjudications and the 6 representing permits. BB stands for basin number. Each
basin assigned a number according to the following table (4.2).
Basin # Basin # Basin #
Canadian 1 Trinity-San Jacinto 9 Lavaca-Guadalupe 17
Red 2 San Jacinto 10 Guadalupe 18
Sulphur 3 San Jacinto-Brazos 11 San Antonio 19
Cypress 4 Brazos 12 San Antonio-Nueces 20
Sabine 5 Brazos-Colorado 13 Nueces 21
Neches 6 Colorado 14 Nueces-Rio Grande 22
Neches-Trinity 7 Colorado-Lavaca 15 Rio Grande 23
Trinity 8 Lavaca 16
Table 4.2: Basin numbers
This system was able to accommodate most points used in the process.
However, USGS ID?s remained the same for USGS stream gages and basin
contractor points were numbered as per their request.
4.3 DEVELOPING THE BASIN STREAM NETWORK
One of the most critical and labor intensive portions of the database
development was the creation of the basin stream network. In order to calculate
watershed parameters, a single-line representation of the basin hydrography was
needed for use in defining a channel network within the DEM. Fortunately, EPA
had developed the RF3 that provided a starting point for this process. However,
39
as stated in Chapter 3, many errors and gaps exist in these files. Also, the RF3
files contain all elements of the basin hydrography, including rivers, lakes,
reservoirs, and canals. Some of these features can interfere with the goal of
developing a single-line stream network. Therefore, for each river basin, an
extensive process of editing and revising had to be performed.
The RF3 files were downloaded from the EPA Basins website at
http://www.epa.gov/ostwater/BASINS/gisdata.html. At the website, the files are
divided into 8-Digit Hydrologic Unit Codes (HUCS). Once downloaded, all the
required files were merged to establish the basic stream network for the entire
basin.
4.3.1 Editing the Stream Network
A single-line network is defined as a network of streams in which only a
single flow path exists from each headwater to the outlet of the basin. This type
of network is required to accurately represent the drainage features of the basin.
Also, in later stages, a single-line network can easily be navigated in order to
determine the connectivity of each point (i.e. which point is downstream or
upstream of another).
The first step in the editing process was to query out all the irregular
features of the network using Arcview. Figure 4.3 shows the command used.
40
Figure 4.3: Query function for eliminating unwanted features in RF3
The ?S? reachtype refers to ?start? reaches while the ?R? reachtype refers
to regular reaches. Once selected, a new shapefile is created from these two
features while all others are deleted. This process eliminates all open water
features, such as lakes, reservoirs, and shorelines. It also eliminates double-line
features, which occur when both sides of wide river sections are delineated in
RF3. Although deleting these features is helpful, it also creates new problems.
With only start and regular reaches remaining, gaps in the network now
existed where the unwanted features were deleted. Figures 4.4 and 4.5 display an
example of how these gaps were created. Once the lakes were deleted, there was
nothing remaining to connect the two streams.
41
Figure 4.4: RF3 before editing
Figure 4.5: Disconnect in RF3 after removing open water features
42
In order to rectify such a problem, the gap had to be filed by a line
representing the flow path through the open water feature. Overlaying the stream
network on the DRG files (as shown in Figures 4.4 and 4.5) helped with this
process. Originally, this step was performed by hand using the editing tools
within Arcview. However, during this project, USGS developed a ?centerline?
file as part of the NHD development that contained flow paths for most of the
open water features in the state. This eliminated the hand-delineation process, but
it was still necessary to ensure that the endpoints of the centerline were attached
to the RF3 network. Also, many of the gaps remaining from small, on-channel
lakes were not included in the USGS centerline coverage and still had to be filled
by hand. An example of an open water feature filled by a USGS centerline is
showninFigure4.6.
Figure 4.6: Reservoir transport path (red) from USGS centerline file
43
Gaps and open water features were not the only issues to be concerned
with in the editing process. Braided stream networks also presented problems
when trying to develop a single-line stream network. Braided streams occur in
marshy areas where the river?s flow can be diverted through a variety of paths.
Again, for this research, only a single path was needed. Therefore, using best
judgment, the most well defined path was chosen as the transport section through
the braided area, and all others were deleted. Figure 4.7 displays an example of a
braided network and the corrections made.
Figure 4.7: Braided stream section with highlighted reaches (yellow) to be deleted
Another problem to be addressed when editing the stream network was the
issue of closed loops. Closed loops occur when part of the channel?s flow is
44
diverted and then reconnects downstream, or to another reach within the network.
In many instances, a closed loop did not affect the overall drainage of the river
network since the flow direction step of the DEM processing (discussed in
Chapter 4) chooses the steepest drainage path. However, there were cases in
which a control point was located on either the diverted stream or a section of the
river downstream of the diversion point. Since this would result in either an
overestimation or underestimation of that point?s drainage area, a decision had to
be made as to which path most accurately defined the network. Again, this
became a judgment call on the part of the researcher. Figure 4.8 is an example of
a closed loop within the stream network.
Figure 4.8: Water right within stream loop
45
4.3.2 Adding Streams to the Network
Although RF3 provided a solid foundation for building a stream network,
it has been shown that many deficiencies still exist. Not only were there
unwanted features, but the opposite problem existed in that there were also many
streams that simply were not included in the file. This fact became particularly
apparent upon receipt of the control point coverages from TNRCC and the basin
contractor. The reason for the missing streams was that both parties used the
1:24,000 scale DRGs as a reference to place the control points. However, since
RF3 was created at the 1:100,000 scale, it did not represent all the minor streams
shown on the DRGs. Therefore, by overlaying the stream network on top of the
DRG, the missing streams needed to connect the points to the stream network
were found. Once the streams were located, new streams were digitized from the
DRG and added to the single-line stream network using the editing tools in
Arcview.
Figure 4.9 shows an area where it was necessary to add streams that did
not exist in RF3. As shown, not only was it necessary to add the stream upon
which the point is located, it was also important to digitize any surrounding
streams. Subtle changes in the land surface can be lost in its conversion to grid
format, depending on the resolution of the DEM. Therefore, adding the
surrounding streams can help to more clearly define the drainage area of small
tributaries.
46
Figure 4.9: Manually digitized (red & yellow) streams added to original RF3 (blue)
4.4 PROCESSING THE DEM
Once a valid, single-line network was created, the next step was to
develop and process the DEM for the basin. At the inception of this project, the
best available DEMs were at the 1:250,000 scale, which contained elevation data
at 90-meter intervals. The DEM data was stored at the USGS website
(http://edcwww.cr.usgs.gov/glis/hyper/guide/1_dgr_demfig/index1m.html)in1
degree by 1 degree boxes. The appropriate files covering the basin were
downloaded from the website and merged together to form one file. Before
clipping the merged file to the extent of the basin, a 10-kilometer buffer was
47
added to the basin boundary in order to capture the drainage features just outside
of the basin. An example of the DEM file for the San Jacinto basin is shown in
the Figure 4.10.
Figure 4.10: San Jacinto basin DEM with basin boundary
After creating the DEM, the file was then processed using an Arcview
extension, CRWR-PrePro, that had been previously developed by the researchers
at CRWR. The first step in the process is called ?burning the streams.? The
stream burning process involves raising all the grid cells surrounding the stream
network by a specified elevation. Essentially, a channel is built in the DEM that
exactly matches that of the stream network. The elevation to raise the grid cells
must be chosen so that it is greater than any other point on the original DEM.
Once the stream network is embedded into the DEM, the second step in CRWR-
48
PrePro, filling, is performed. The filling process searches the DEM for small
sinks and pits. Since these pits can unnecessarily capture water in the terrain, they
must be filled by raising the elevation of the pits to that of the surrounding cells.
After burning and filling, the resulting grid is then run through the flow direction
process. In this step, the flow direction of each cell in the grid is determined by
examination of the elevations in each surrounding cell. Thus, the steepest slope
determines the cell?s flow direction. This process is needed to determine the areas
of the terrain that flow into each stream. The final step in CRWR-PrePro is the
flow accumulation process. This function uses the newly created flow direction
grid to determine the number of upstream cells above each point in the basin.
Throughout the basin, each cell is assigned a value that is representative of all the
cells draining to that point. Thus, a greater cell-count refers to a larger drainage
area. Figures 4.11 and 4.12 show the flow direction and flow accumulation grids,
respectively.
49
Figure 4.11: Flow direction grid of San Jacinto basin
Figure 4.12: Flow accumulation grid of San Jacinto basin
50
4.5 COMPUTING THE WATERSHED PARAMETERS
The processed DEM files form the basis for the watershed parameter
calculations. The drainage area for each point was calculated from the flow
accumulation grid. Also, using the grid program within Arc/Info, the basin
precipitation and curve number grids were combined with the flow direction and
flow accumulation grids to compute the average precipitation and curve number
grids. The third parameter, next downstream point, was found by simply
checking each point by hand. This section details these procedures.
4.5.1 Calculating Drainage Area
As stated, the flow accumulation grid calculates the number of cells in the
basin flowing to each point. Thus, by checking the flow accumulation value at a
point, only a simple calculation is needed to find the drainage area.
)mi/(m2589988
)(msizecellcellsof#
)(miAreaDrainage
22
22
2
?
= (Eqn. 4.1)
However, the main issue in this process was ensuring that the control
points were located on the appropriate flow accumulation grid cell. Initially, the
points had only been placed on the stream network. However, at the end of the
DEM processing, the stream network may no longer fall along the path of the
flow direction grid. This happens when the stream network crosses more than one
cell at a time while the flow direction function can only choose one path. Figure
4.13 shows such an example.
51
Figure 4.13: An incorrectly located control point
As shown, an incorrectly located control point can result in a drastic error
in reported drainage area because the point location does not lie over a grid cell
onthestreamnetwork. Inthepresentlocation,adrainageareaof0.01square
miles would be reported, rather than the true area of 2837 square miles (8163850
cells of 30-meter size). At the time, the solution to this problem was to check
each point by hand against the flow accumulation grid to determine its proper
location. However, over the course of the project, an automated system was set
up to correct these types of problems. This method will be presented in the case
study of the San Jacinto basin.
52
4.5.2 Calculating Average Curve Number and Precipitation
Along with drainage area, the two other parameters needed for each point
were the average curve number and average precipitation across the control point
watershed. As with the DEM, curve number and precipitation grids already
existed for the state. Therefore, in order work with them, they simply had to be
clipped to the spatial extent of the basin boundary. The only difference in this
step was that the existing CN and precipitation grids were sampled at different
resolutions than the DEM. So, before proceeding, each grid had to be resampled
to the same cell size and extent of the basin DEM. The following Arc/Info
commands serve this purpose (Note: Words in all caps represent generic file
names):
Grid: setcell DEM DEM
Grid: setwindow DEM
Grid: NEWPRECIP = PRECIP
Grid:NEWCN=CN
At this point, each of the new grids has the same cell size as the DEM.
However, the extent of the new grids is still that of the original grids (i.e. the
entire state). In order to continue working with the parameter calculations, the
grids first have to be resized to that of the basin. Using a conditional function in
Arc/Info, the flow direction of each cell was queried. If the value of the flow
direction grid was greater than zero, the corresponding cell in the precipitation
and/or CN grid was kept. This ensured that only the precipitation and CN grid
cells within the basins were kept, thus creating a grid that exactly coincided with
53
the flow direction grid. The following Arc/Info commands were used in the
resizing:
Grid: NEWPRECIP = con (FDR > 0, NEWPRECIP)
Grid: NEWCN = con (FDR > 0, NEWCN)
The final step in calculating curve number and precipitation values for the
control points was to create a weighted flow accumulation grid from the newly
created precipitation and CN grids. Mathematically, an average CN or
precipitation over several areas can be calculated by performing a weighted
average (i.e. dividing the sum of the products of each area and parameter by the
total area). Therefore, the same idea can be applied when working with grids. To
find the average CN of a certain location, the sum of the products of each
upstream cell and its CN value is divided by the total number of cells in that
location?s drainage area. The following Arc/Info command was used to create the
average CN grid for the basin.
Grid: AVGCN = (flowaccumulation (FDR, NEWCN) +
NEWCN) / (FACC + 1)
By substituting the precipitation grid in place of the CN grid, the average
precipitation grid for the basin was calculated in a corresponding manner.
4.5.3 Reporting the Control Point Parameters
With the control points in place, and all required grids calculated, the final
step was to produce a table of watershed parameters for each point. In the early
stages of this project, the parameter table was created by manually checking each
control point and inserting its corresponding parameters into a table. However,
54
with hundreds of control points to consider, this method proved to be quite
tedious and time consuming. A script written by Patrice Melancon was able to
query raster files at the same location of a point and insert the grid values into a
table. Thus, this script was modified by Brad Hudgens to incorporate the needs of
the WAM team. The output of this script was a new control point coverage with
the values of drainage area, average CN and average precipitation in the attribute
table. The following is an example of the parameter attribute table.
Figure 4.14: Excerpt of parameter attribute table
Along with the attribute table, watershed delineations had to be produced
for each of the control points in the basin. Again, CRWR-PrePro was used for
this task. The extension reads the flow direction grid upstream of each point and
draws a boundary around the area flowing to that location. If a point exists
55
upstream, the extension produces an incremental watershed between the two
points.
4.6 EVALUATING THE QUALITY OF PARAMETERS
Since many of the parameter calculations were performed in an automated
fashion, a great deal of effort was spent on quality control. First, an evaluation
was made as to which parameter was the most important factor in producing
accurate results. As stated, both the CN and precipitation values were based on
weighted averages using the control point drainage areas. Since there was no
legitimate way to modify the accuracy of the original CN and precipitation grids
themselves, it became clear that the drainage area calculations were the most
sensitive parameter within the methodology. Also, enhancing the accuracy of the
drainage areas would consequently improve the average CN and precipitation
values. Clearly, it would be impossible to check the drainage area for each point
in the basin. Therefore, a method had to be devised that would cover a
representative, yet manageable amount of data.
The first check performed for quality control was the evaluation of the
stream gages and other known flow locations. USGS records contain drainage
area values for each stream gage location. Therefore, it was a simple task to
check the model drainage areas against the widely accepted USGS values. Also,
the respective basin contractors provided drainage area values for known flow
points in the basin to be modeled. Table 4.3 shows a comparison of drainage
areas for the Nueces basin stream gages and known flow control points (in this
case, known flow values were provided by HDR, Inc).
56
Table 4.3: Drainage area comparison for Nueces basin control points
As shown, a majority of the points fall within a relative difference of
approximately 1 to 2 percent. However, these very small percentages hide large
discrepancies in total drainage area. For example, control point 29 shows a
difference of only 1.30%, but the actual values differ by over 200 square miles.
57
The watersheds for points such as this were checked against the DRG topography
to rectify these errors. Reasons for such discrepancies included errors in the
stream network and deficiencies in the 1:250,000 scale DEMs to represent terrain
relief in the flatter areas of the basin. Solutions to these problems will be
presented in the case studies to follow.
The second step in the quality control process was to check the smaller
watersheds in the basin. Experience with watershed delineations from 1:250,000
scale DEMs revealed that areas with a flow accumulation of less than 1000 cells
contained a high probability of delineation areas. Elevation data at 90-meter
intervals was simply not sufficient enough to represent changes in topology of
small areas. Therefore, each watershed below 1000 cells in size was checked
visually against the DRGs. If a discrepancy was found, a new watershed was
digitized manually with the editing tools in Arcview. The validity of the 1000
cell threshold is discussed in the results section of this thesis
4.7 CONCLUSION
The steps presented in this chapter represent an overview of the
methodology used at the outset of this research. Using data compiled by CRWR,
TNRCC and the basin contractor developed the control point coverages to be
modeled for the basin. During this time, a single-line stream network was
constructed from the EPA?s RF3 file. Once the points were returned, the location
of each was checked against the newly created stream network. If a point was not
on the stream network, the location was verified against the DRGs and a new
stream was digitized into the network. After the final stream network was
58
completed, the DEM was processed using the CRWR-PrePro extension in
Arcview. The next step was the development of the average CN and precipitation
grids. A script was then run to extract all the parameters for each control point.
Finally, an extensive quality control procedure was performed to check the
accuracy of the results.
The methods described in this chapter provide the basis for all the work
performed in this research. However, as problems were encountered, the process
was changed to eliminate shortcomings in the methodology and to improve the
overall accuracy of the results. The next 3 chapters entail case studies of each
river basin in the study area.
59
CHAPTER 5: CASE STUDY ? NUECES BASIN
5.1 INTRODUCTION
The Nueces river basin is located in South Texas (see location map in the
study area section of Chapter 1) and services all or parts of 22 counties, with its
rivers and tributaries draining an area of approximately 17,000 square miles. The
basin contractor for the Nueces was HDR, Inc, located in South Austin. At the
outset of the study, HDR decided that it did not need precipitation and curve
number information, but would instead need flow length values for each point.
These flow length values would be used to calculate channel losses in order to
distribute known flows throughout the basin. Other than this change, the first
processing run followed the same methods described in Chapter 4. However,
once it became apparent that there was discrepancies in the drainage areas
reported by CRWR and those established by USGS, changes in methodology
were made. The following sections provide an analysis of the problems
encountered, the changes that were made, and the effect that these changes had on
the final results.
5.2 RESULTS FROM FIRST RUN
As stated, the files needed for the Nueces basin were generated using the
same methodology outlined in Chapter 4. Figure 5.1 shows the critical
geographic themes in the project: control points, stream network and DEM.
60
Figure 5.1: Nueces basin layout
There were 517 control points for which parameters were needed. Of
these, 22 were USGS gage locations, 13 were contractor identified known flow
locations (mainly points along the Edwards aquifer recharge zone), 13 were
stream confluence locations (used for channel loss calculations), and the
remaining 469 were water right/diversion locations. HDR specified the
61
placement of the USGS, known flow, and confluence locations. For each point, a
scanned topographic map was sent to CRWR to ensure proper placement. The
water right/diversion points were checked and edited by TNRCC, and then
returned to CRWR. All the points were then merged into one file.
The stream network was edited under normal procedures using the DRG
as a reference. The main problem encountered with the Nueces was the existence
of many braided stream segments. Each section of this nature had to be checked
thoroughly in order to define one, clean drainage path. Another problem
encountered was the existence of several streams in the RF3 file that crossed the
established basin boundary. These extraneous segments had to be located and
deleted in order to prevent the inclusion of areas not within the basin.
The DEM was built using 90m data (1:250,000) from the USGS website.
The files were downloaded in 1 degree by 1 degree blocks, merged together,
clipped to the basin, and then buffered 10km. Once completed, the DEM was
processed, along with the final stream network, using the CRWR-PrePro
extension. The required flow length grid was easily generated from the processed
flow direction grid using the Hydrology extension in Arcview. This extension
creates a grid with the length of flow from each cell to the outlet of the basin.
After placing all the points on the proper flow accumulation cell, the
values of flow accumulation and flow length were reported and the watersheds
were delineated. Upon checking the values of the USGS gages and known flow
locations, it was clear that some errors did exist. Table 5.1 presents a comparison
of CRWR reported values and USGS/HDR values.
62
Point CRWR USGS HDR Difference Error
ID mi
2
mi
2
mi
2
%
1 757.34 737 20 2.76
2 687.56 694 -6 -0.93
3 1863.73 1861 3 0.15
4 4158.02 4082 76 1.86
5 5307.64 5171 137 2.64
6 8284.85 8093 192 2.37
7 393.95 389 5 1.27
8 124.32 126 -2 -1.33
9 638.16 631 7 1.13
10 33.94 36 -2 -5.72
11 31.77 32 0 -0.72
12 209.68 206 4 1.79
13 248.03 241 7 2.92
14 18.02 18 0 0.11
15 4.37 6 -2 -27.17
16 45.48 45 0 1.07
17 165.23 168 -3 -1.65
18 97.59 96 2 1.66
19 153.39 149 4 2.95
20 12.00 12 0 0.00
21 57.57 55 3 4.67
22 104.93 105 0 -0.07
23 47.21 47 0 0.45
24 138.99 Spring N/A N/A
25 3431.05 3429 2 0.06
26 784.33 783 1 0.17
27 5480.88 5490 -9 -0.17
28 1158.43 1171 -13 -1.07
29 15628.00 15427 201 1.30
30 16722.87 16660 63 0.38
31 16986.07 16920 66 0.39
Table 5.1: Comparison of CRWR reported values and established drainage areas.
In general, most of the CRWR values were within an acceptable range of
the USGS drainage areas. However, the highlighted records denote points that
63
had significant errors in either relative difference or relative percent error from
established values.
The errors in control point CP10 and CP15 stand out due to the percent
error. As shown, the established drainage areas for these two points are 36 and 6
square miles, respectively. Due to such a small size, any difference in area results
in a large percent error. The placement of these points was established by HDR
and CRWR was instructed to adjust the location of these points up or down the
stream until the drainage area matched the value that HDR had previously
established. Therefore, these two points were moved downstream on the tributary
to a location just above the junction of its connecting stream. Moving the points
any further resulted in a large jump in drainage area. So, the values reported in
the table represent the closest values obtained by CRWR. The small error of 2
square miles for each represents a limitation of the 90-meter data to accurately
capture the drainage features of small watersheds.
Although the percent errors of points 4, 5, 6, 29, 30, 31 were relatively
low (roughly 2% or less), Table 5.1 shows a significant discrepancy in total
drainage area as compared to USGS values. All the points were located along the
main stem of the Nueces River, with CP4 near the upper end and CP31 near the
outlet. Moving downstream from CP4, the error in drainage area continued to
increase. Therefore, it can be shown that a majority of the discrepancy
(approximately 75 square miles) was found in the watershed of CP4, and that
64
error was carried downstream through the remaining points. However, not only
was the error being transferred, but additional area was also being added. By the
time it reached CP29, the error had risen to 200 square miles.
On the whole, the majority of major errors in drainage area were positive,
meaning CRWR was reporting values higher than that of USGS. Had some of the
errors been negative, an assumption could have been made that one gage was
taking area from another. However, the fact that CRWR was reporting a
continuously higher drainage area means that additional area was being captured
from outside the basin. Therefore, the first place to look for corrections was the
area around the basin boundary.
From a comparison of the watershed file and the established basin
boundary, it was found that the CRWR delineated basin boundary fell outside the
established basin boundary. The discrepancies were particularly noticeable in
areas with low relief, such as the western portion of the Nueces and the area near
the coast. This error can also be attributed to deficiencies in the 90-meter data to
accurately reflect small changes in the flat terrain. At this point in the research,
however, data of higher resolution (such as 30-meter data) was not available. A
diagram showing the errors in the CRWR delineation is shown in Figure 5.2.
65
Figure 5.2: CRWR boundary (red) overlain on established boundary (black)
5.3 CHANGE IN METHODOLOGY
Without a DEM of higher resolution, a change in methodology had to be
devised in order to prevent the additional capture in drainage area. One option
was to build an artificial wall in the DEM by raising the cells along the existing
basin boundary by an arbitrary amount. However, this method would serve to
falsify the solution of the watershed delineator rather than using its capability to
read the terrain.
66
Therefore, the solution settled upon was to burn additional streams into the
basin buffer. The RF3 files from the basins surrounding the Nueces were merged,
clipped to the basin buffer, and burned into the DEM along with those of the
Nueces basin. The newly burned in streams would carry water away from the
basin boundary from both sides, thus providing a more accurate depiction of the
landscape. Figure 5.3 shows the close agreement between the new watershed
delineation and the established basin boundary.
Figure 5.3: New watershed delineation overlain on basin boundary
67
5.4 RESULTS FROM SECOND RUN
The addition of the streams within the buffer had an obvious effect on the
overall watershed delineations. Figure 5.3 showed how closely the watersheds
matched the basin boundary, even in the flat, problematic areas from the first run.
The following table (5.2) shows the drainage area results from the second run.
Control CRWR (mi
2
) Difference (mi
2
) Error %
Point Version Version Version
ID2121 21
1 757.35 757.34 20 20 2.76 2.76
2 687.10 687.56 -7 -6 -0.99 -0.93
3 1863.16 1863.73 2 3 0.12 0.15
4 4045.47 4158.02 -37 76 -0.89 1.86
5 5193.11 5307.64 22 137 0.43 2.64
6 8144.20 8284.85 51 192 0.63 2.37
7 393.18 393.95 4 5 1.07 1.27
8 124.32 124.32 -2 -2 -1.33 -1.33
9 637.42 638.16 6 7 1.02 1.13
10 33.96 33.94 -2 -2 -5.67 -5.72
11 31.77 31.77 0 0 -0.72 -0.72
12 208.49 209.68 2 4 1.21 1.79
13 246.82 248.03 6 7 2.41 2.92
14 18.03 18.02 0 0 0.17 0.11
15 4.39 4.37 -2 -2 -26.83 -27.17
16 45.19 45.48 0 0 0.42 1.07
17 165.23 165.23 -3 -3 -1.65 -1.65
18 97.42 97.59 1 2 1.48 1.66
19 153.20 153.39 4 4 2.82 2.95
20 12.00 12.00 0 0 0.00 0.00
21 57.46 57.57 2 3 4.47 4.67
22 105.08 104.93 0 0 0.08 -0.07
23 46.88 47.21 0 0 -0.26 0.45
24 138.99 138.99 N/A N/A N/A N/A
25 3428.13 3431.05 -1 2 -0.03 0.06
26 784.26 784.33 1 1 0.16 0.17
27 5478.07 5480.88 -12 -9 -0.22 -0.17
28 1148.67 1158.43 -22 -13 -1.91 -1.07
29 15460.55 15628.00 34 201 0.22 1.30
30 16542.09 16722.87 -118 63 -0.71 0.38
31 16720.74 16986.07 -199 66 -1.18 0.39
Table 5.2: Comparison of drainage areas from first and second runs.
68
As shown, the errors in CP4, 5, 6, and 29 were significantly reduced in
both percentage and total difference by simply adding streams to the buffer. This
confirmed the assumption that the reason for the errors was due to the capture of
area from outside the Nueces basin. However, the change in methodology
actually produced worse result for points CP30 and CP31. In fact, instead of the
overestimation that was found after the first run, the values for CP30 and CP31 in
the second run were significantly lower than the USGS values.
Again, the drainage boundaries from the watershed file were compared
with that of the established basin boundary. As shown previously in Figure 5.3,
the boundaries matched almost perfectly for most of the basin. However, near the
coast, there was still a bit of deviation, as shown in Figure 5.4.
Figure 5.4: Lower portion of Nueces basin with CP30 (left) and CP31 (right) highlighted.
69
It can be seen from Figure 5.4 that the new watershed boundary does fall
slightly inside of the established boundary. However, the difference does not
seem to account for the almost 200 square mile difference shown for CP31 in
Table 5.2. Therefore, it was then necessary to look at the incremental differences
between the points at the lower end of the basin, specifically CP29, CP30, and
CP31. Table 5.3 shows the incremental areas between the points.
Point CRWR USGS Incremental Difference
ID mi
2
mi
2
CRWR USGS
29 15461 15427
30 16542 16660 1081 1233
31 16721 16920 179 260
Table 5.3: Nueces Basin incremental areas.
Immediately, a 150 square mile difference was revealed in the incremental
area between CP29 and CP30. Upon investigation of the watershed between the
two points, there were not any significant discrepancies that would account for
such a difference. HDR investigated old USGS records and found that the
drainage area for CP30 had been copied errantly back in 1940 and the error had
gone unnoticed until now. Once corrected, the CRWR areas more closely
matched the new USGS numbers and were acceptable to the basin contractor.
5.5 UNRESOLVED ERRORS
Although the addition of streams into the basin buffer eliminated the
problems in the large watersheds that coincide with the basin boundary, the
change did nothing to remedy problems in small watersheds and the middle
70
portion of the basin. Through the quality control procedures, incidents of short-
circuiting and incorrectly delineated watersheds below the 1000 cell flow
accumulation threshold were found.
5.5.1 Short-Circuiting
Short-circuiting of the river network occurs when the flow direction grid
and subsequent flow accumulation grid do not match the original stream network,
asshowninFigure5.5.
Figure 5.5: Stream network overlain on burned DEM.
71
This problem of short-circuiting usually occurs when using files of vastly
different scales, as stated by Saunders (1999). From the figure, it is clear that the
network should remain as two separate channels until the junction at the bottom
of the frame. However, the burned channel shows a junction prematurely when
the two stream channels get within one cell of each other. Later in the processing,
only one of the channels will be chosen when creating the flow direction grid,
thus causing an error in the flow accumulation of the other channel. Fortunately,
in this section of the basin, there are no control points. However, short-circuiting
becomes problematic when points are located along either section of the stream
between the short circuit and the true junction. In that case, the drainage area of
the control point has to be adjusted to arrive at the true value.
One solution to this problem is to manually adjust streams that appear to
be too close during the original RF3 editing process. However, moving the
streams could also adjust other features in the drainage scheme and is not
recommended. The only real solution was to use higher resolution DEMs whose
cells would be able to more closely represent the stream network. At this point in
the research, without higher resolution grids, the basin had to be checked
thoroughly by hand to correct for any short-circuiting.
5.5.2 Quality Control Watersheds
As stated in Chapter 4, a second element of the quality control procedure
was to check all watersheds below a flow accumulation value of 1000 cells
(approximately 3 square miles). Through other research projects at CRWR, the
72
value of 1000 cells has been found to be a good starting threshold for quality
control work when using 90-meter data.
After performing a query on the control point file, 68 points of the 517
points in the basin had a flow accumulation value of less than 1000. Immediately,
15 of those points were eliminated since they were either off-channel reservoirs or
points that had already been corrected due to short-circuiting errors. Each of the
remaining 57 control point watersheds were checked visually against the DRG
maps to determine whether the delineations were performed accurately. If errors
were found, a new watershed was delineated by hand, as shown in Figure 5.6.
Figure 5.6: Hand-delineated watershed for quality control
73
The original watershed had an area of 0.68 square miles while the newly
delineated watershed had an area of 0.51 square miles. As shown, the newly
delineated watershed more closely fits the drainage features of the terrain. Of the
57 points checked, 11 were properly delineated by CRWR-PrePro, while the
remaining 46 had to be delineated in the same manner as shown in Figure 5.6.
Possible solutions to errors in the smaller watersheds are the use of higher
resolution stream networks and DEMs.
5.6 CONCLUSION
In general, the results generated for the Nueces basin after adding the
buffered streams were satisfactory. Almost all the values found by CRWR were
within 2 percent of the known flow values defined by USGS and HDR. For a
complete list of control points and parameters, see Appendix A.
After performing the quality control procedures, all instances of short-
circuiting were found and corrected. Also, watersheds were delineated by hand
for those sub-watersheds incorrectly defined by CRWR-PrePro, which mainly
consisted of watersheds below the 1000 cell threshold.
Upon completion of the Nueces basin, it was suspected that most of the
problems encountered could be eliminated by using higher resolution DEMs that
more closely fit the terrain and scale of the stream network. The new 30-meter
datasets became available just after the conclusion of work on the Nueces basin
and were used for the remainder of the research. Results obtained from the new
dataset are found in Chapters 6 and 7.
74
CHAPTER 6: CASE STUDY ? GUADALUPE & SAN ANTONIO
BASINS
6.1 INTRODUCTION
The Guadalupe and San Antonio river basins are also located in South
Texas, adjacent to the Nueces basin (refer to map in Chapter 1). In fact, the San
Antonio runs along the eastern edge of the Nueces basin, while the Guadalupe
runs along the eastern edge of the San Antonio basin. Near the coast, the San
Antonio joins the Guadalupe before exiting into the Gulf. At that point, the total
area of the two basins is 10,125 square miles, with 5954 square miles contributed
by the Guadalupe and 4171 square miles contributed by the San Antonio. Again,
the basin contractor for these two basins was HDR, Inc. Since the San Antonio
flows into the Guadalupe, HDR modeled the two basins as one unit. However,
for the purposes of this research, each basin was processed separately.
As with the Nueces, average precipitation and curve number parameters
were replaced by the flow length parameter for both basins. The basins were first
processed using the procedure described in Chapter 4. However, through
experience with the Nueces and the recent availability of 30-meter data, changes
in the methodology were made and the basins were entirely reprocessed. The
following chapter discusses the results obtained from the use of 90-meter data, the
changes made to accommodate the 30-meter data, and the final results calculated
from the new datasets.
75
6.2 RESULTS FROM FIRST RUN
As stated, each basin was first processed using the original procedure
outlined in Chapter 4. The critical files for each basin are shown in Figures 6.1
and 6.2. These files include the 90-meter DEM, the single-line stream network,
and the basin control points.
Figure 6.1: Layout of Guadalupe River basin
76
Figure6.2:LayoutofSanAntonioRiverbasin
There were a total of approximately 1300 control points (800 and 500 for
the Guadalupe and San Antonio basins, respectively) for which parameters were
needed. Of these 1300 points, 30 were USGS gage locations, 10 were contractor
identified known flow locations, 40 were stream confluence locations, and the
remaining 1220 were water right/diversion locations. Again, all known flow and
confluence points were placed by HDR, while TNRCC located the water
77
right/diversion points. Once completed, all points were sent to CRWR and
merged into one master file for each basin.
The stream network editing process went much more smoothly with the
Guadalupe and San Antonio basins due to the lack of braided streams. Also,
TNRCC provided stream edits with the water right files that were merged into the
existing network. This saved CRWR time in manually checking each of the
points for placement on existing streams. Also, another improvement from the
Nueces editing process was the existence of the USGS centerline file. Instead of
manually digitizing streams in place of the deleted open-water features, the USGS
NHD centerlines were merged into the existing network to fill any gaps.
The 90-meter data was processed in the same manner as the first run of the
Nueces. The grids for each basin were downloaded, merged, clipped, and
buffered. The DEMs and stream networks were then processed separately using
CRWR-PrePro. Also, the flow length grid was generated using the Hydrology
extensioninArcview.
Without the tools created later to automate the point placement process,
each of the 1300 points had to be placed and checked manually to ensure proper
location on the flow accumulation grid. For such a large coverage, this process
proved to be very long and tedious, requiring the work of several researchers over
the span of a week. Once all the points were placed, the values of flow
accumulation and flow length were reported and the incremental watersheds for
each point were delineated. Since this process had previously been performed on
78
the Nueces, errors were anticipated. The following sections detail the errors
found in the Guadalupe and San Antonio, respectively.
6.2.1 Guadalupe Results
With all the parameters generated, the first step was to check the accuracy
of the USGS gage locations and the HDR known flow locations. Table 6.1
presents a comparison of these known flow locations and the CRWR reported
values.
Point CRWR USGS HDR Difference Error
ID
mi
2
mi
2
mi
2
%
1 870.83 839 32 3.79
2 1353.13 1315 38 2.90
3 1471.73 1432 40 2.77
4 1560.92 1518 43 2.83
5 136.37 130 6 4.90
6 2103.38 2103 0 0.02
7 94.13 94 0 0.14
8 359.75 355 5 1.34
9 417.92 412 6 1.44
10 848.1 838 10 1.21
11 323.07 309 14 4.55
12 480.15 460 20 4.38
13 593.68 549 45 8.14
14 5078.28 4934 144 2.92
15 5419.05 5198 221 4.25
16 519.48 494 25 5.16
38 N/A 10128 N/A N/A
Table 6.1: Comparison of CRWR reported values and established drainage areas
Clearly, it can be seen that the results from the first run of the Guadalupe
were not satisfactory. The highlighted control points show locations with a
relative area of greater than 3%, which includes half of the USGS gage locations.
Also, the table shows that the remaining errors for the gages were between 1.5%
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and 3%. Another thing to note is that every CRWR value was higher than either
the USGS or HDR known drainage area. This fact signifies a specific problem of
drainage area being captured from outside the established basin boundary. The
reason for higher errors than the Nueces across the board is due to the relative size
of the two basins. Since the Guadalupe basin is much smaller, any errors in
drainage area are magnified.
When inputted into the water availability model, the USGS gages are used
to calculate the flows at all other points in the basin through a drainage area ratio.
Therefore, there is no reason to study the accuracy of the remaining control points
within the Guadalupe until the errors in the gages are corrected. Therefore,
further study of the Guadalupe can be found in section 6.4 of this chapter.
6.2.2 San Antonio Results
With the Guadalupe, San Antonio and Nueces all in such close proximity
to each other, the same types of errors were expected in the results of the San
Antonio as were found in the others. However, the fact that each of the basins
were being processed almost simultaneously due to project deadlines meant that
the first run of the San Antonio was also performed using the original procedures
outlined in Chapter 4. Surprisingly, the results from the first run were quite
promising, as shown in Table 6.2.
80
Point CRWR USGS HDR Difference Error
ID
mi
2
mi
2
mi
2
%
17 7.75 8.3 -1 -6.63
18 46.79 41.8 5 11.94
19 140.36 137 3 2.45
20 191.56 189 3 1.35
21 639.42 634 5 0.85
22 15.00 15.6 -1 N/A
23 655.00 650 5 0.77
24 9.89 13.1 -3 -24.50
25 57.96 58.3 0 -0.58
26 99.74 99.7 0 0.04
27 975.54 967 9 0.88
28 1326.63 1317 10 0.73
29 1782.49 1743 39 2.27
30 7.97 9.4 -1 -15.21
31 65.43 65.4 0 0.05
32 2137.81 2113 25 1.17
33 68.17 68.4 0 -0.34
34 271.01 274 -3 -1.09
35 824.98 827 -2 -0.24
36 257.95 239 19 7.93
37 3972.22 3921 51 1.31
Table 6.2: Comparison of CRWR reported values and established drainage areas.
In general, the CRWR reported values closely matched that of the USGS
and HDR. The highlighted records show 6 points that have particularly high
errors in relative percent and/or difference. However, 3 of these 6 points are HDR
established known flow locations, for which CRWR was instructed to fit the
values as closely as possible (as referenced in section 5.2). The 12 percent error
in CP18 was produced by only a 5 square mile difference in area, which can be
considered negligible in such a study. The errors in CP36 and CP37 were the
result of the same problems encountered in the Nueces and Guadalupe. The
81
watershed of each point ventured outside the established basin boundary,
capturing area from the adjacent basin.
The exact reason for such improved results in the first run of the San
Antonio over the first runs of the other two basins was not known. The
researchers at CRWR have noticed differences in the quality of the DEM and the
density of the original RF3 network in varying locations. Or, it may simply be
that experience gained in building the stream networks for the first two basins in
the study led to an improved effort in building the network for the San Antonio
basin. At any rate, it was clear that there was room for improvement in the
methodology, particularly with respect to the scale of the DEMs being used in the
processing. It was at this point in the research that a seamless, 30-meter DEM for
the entire state of Texas was completed by USGS.
6.3 CHANGES IN METHODOLOGY
In addition to the incorporation of streams in the buffered area, the
availability of the 30-meter dataset was a clear indicator of the next possible
improvement in the methodology. Obviously, a more defined terrain would
produce more accurate drainage areas across the basin, and could even eliminate
errors in places of low relief. Also, the 30-meter (1:24,000 scale) DEM would
more closely fit the 1:100,000 scale river network, thus eliminating many of the
short-circuiting problems experienced with 90-meter data.
Some anticipated problems with using the 30-meter DEM were increased
file size and processing time. For example, the file size of the Guadalupe DEM
was only 3 MB at 90-meter resolution, but increased to 57 MB at 30-meter
82
resolution. The reason for this drastic increase was the number of cells stored in
the higher resolution grid. The 90-meter DEM for the Guadalupe contained 9
million cells, while the 30-meter DEM contained 80 million cells. Also, since
CRWR-PrePro works on a cell-by-cell basis, the increase in cells resulted in an
increase in processing time, as discussed in the next section..
Previous research at CRWR indicated that Arcview might have a problem
performing calculations on such large grids. It was suggested that a cell threshold
of approximately 40 million exists and, if exceeded, would cause the system to
crash. Before trying other options, the threshold was put to test and the system
did, in fact, crash during the initial processing of the DEM. Therefore, the
alternatives were to process the DEM using Arc/Info, or divide the basin into
smaller, manageable parts. The next two sections explain both of these
alternatives.
6.3.1 Processing DEM using Arc/Info
Without the built in commands of the CRWR-PrePro extension, a new
method had to be devised for performing the same tasks in Arc/Info. However,
the stream network file first had to be converted to a grid in Arcview before being
incorporated into Arc/Info. Also, the resulting grid had to contain values of one
along the stream cells, and no data everywhere else. So, a new field was added to
the stream network attribute table that contained a value of one for every arc in
the shapefile. Then, during the conversion, Arcview asked for the column in the
table to be used for the grid ID values. At this point, the newly created field was
chosen.
83
Once the necessary stream grid was created, it was then taken into the
Arc/Info format for further processing. First, the stream grid was multiplied by
the DEM to produce a new stream grid with values of elevation along the streams,
rather than values of 1. Next, an elevation increment of value greater than the
highest peak in the DEM was added to the original DEM. This produced a new
DEM that had simply been raised a certain height. Next, the new stream and
DEM grids were joined using the merge command in Arc/Info. The result of the
merged grids was the Burned DEM.
At this point, a prompt in Arc/Info stated that a value attribute table (VAT)
has not been created for the Burned DEM. This prompt was an indication of the
cell threshold spoken of earlier. Arc/Info automatically builds the VAT file for
grids up to a certain size and prompts the user to build one if the grid is too large.
However, Arcview simply crashes if the grid is too large. Therefore, before
continuing, a VAT file for the Burned DEM was built using the buildvat
command in Arc/Info.
The next step in the process was the creation of the FILL, FDR, FACC
grids. Commands in Arc/Info already existed to perform these tasks. The fill
command used the Burned DEM as an input to create the Filled DEM. During
this process, the FDR was created automatically. Finally, the flowaccumulation
function used the FDR grid to create a flow accumulation grid (FACC).
One advantage of processing the grids in Arc/Info is that the system
allows the user to input all the necessary functions in the form of a text file. This
way, a batch process can be set up so that the user does not need to input each
84
command as the previous one is completed. Below are the commands used in the
grid processing.
Grid: setcell DEM
Grid: setwindow DEM
Grid: DEMSTREAM = STRMGRID * DEM
Grid: DEMPLUS = DEM + 10000
Grid: BURNDEM = merge (DEMSTREAM, DEMPLUS)
Grid: buildvat BURNDEM
Grid: fill BURNDEM FILLDEM # # FDR
Grid: FACC = flowaccumulation (FDR)
Once the flow accumulation grid was created, the control points were
relocated to the proper flow accumulation cell in the Arcview format. Then, in
the same manner as the stream network, the control points were converted to a
grid using the control point ID numbers as the values for the new grid cells. Next,
back in Arc/Info, the control point grid and FDR grid were used as inputs into the
watershed function to create the watershed delineations, as shown by the
following command.
Grid: WTRSHEDS = watershed (FDR, CPGRID)
The first few attempts at grid processing using Arc/Info resulted in error
messages. During the fill process, several large, temporary grids were created that
filled the entire hard-drive of the computer. However, once enough space was
cleared to accommodate the fill step, the rest of the processing went smoothly. As
anticipated, the processing time required for the 30-meter grids was quite long.
The run-time to complete the burn, fill, flow direction, and flow accumulation
85
steps for the Guadalupe was approximately 15 hours. The same task for the 90-
meter data was completed in approximately 1 hour.
6.3.2 Sub-dividing the Basin DEM
For both the Guadalupe and San Antonio basins, the grid processing was
completed without having to divide the basins into smaller parts. However, after
the first few failed attempts due to lack of space on the hard-drive, a method for
sub-dividing the basins into smaller parts was devised. Although, in the end, the
method was not utilized for the San Antonio and Guadalupe, the method could be
used for processing the larger basins in Texas (namely, the Trinity, Brazos, and
Colorado). Therefore, the methodology to complete the sub-division was
included in this case study.
The first step was to decide upon an appropriate amount of sub-divisions
for the basin. It is recommended to divide the basin into parts of no greater than
15-20 million cells for processing efficiency. Polygons built from a combination
of 8-digit HUCs were used. With the polygons chosen, points had to be placed on
the stream network at the outlet of each polygon. These locations would then be
converted to grids for use in later stages of the processing. The generated
polygons were then used to clip and buffer the DEM. The sub-sections of the
DEM were then processed using CRWR-PrePro in Arcview or the commands
described previously for Arc/Info.
The main challenge of this process was to be able to transfer the flow
accumulation from an upstream sub-basin to the next sub-basin downstream. This
task was also complicated by the presence of the basin buffer for each of the sub-
86
basins. The commands used to accomplish this task and descriptions of each
command will follow. Also, Figure 6.3 can be used as a visual reference,
Figure 6.3: Diagram of sub-division process
where: STATIONGR = Control point at basin boundary
FACCUS = Upstream flow accumulation grid
FDRDS = Downstream flow direction grid
STATIONWSH = Watershed above STATIONGR using FDRDS
Since the two basin buffers overlap, the conjoined area between the two
must be eliminated to prevent double counting the area. So, the first step was to
generate a watershed above the control point that was placed at the basin
boundary previously. The following command accomplished this step.
Grid: STATIONWSH = watershed (FDRDS, STATIONGR)
87
Notice the watershed was generated from the downstream basin only.
This ensured that the watershed extended only from the control point to the upper
end of the downstream basin.
The next step was to create a weight grid that would only include the
upstream flow accumulation at the control point, and values of zero for all other
cells within the STATIONWSH. A grid with values of zero at every cell was
created with the following command.
Grid: WEIGHT0 = con (STATIONWSH > 0, 0)
To create a grid with only the value of the upstream flow accumulation at
the control point location, the control point grid was first divided by itself,
producing a grid with a value of one at the control point location and no data
everywhere else. This grid was then multiplied by the upstream flow
accumulation grid to produce the desired grid.
Grid: WEIGHTST = (STATIONGR/STATIONGR)*FACCUS
Finally, the two weight grids just created were merged to form the grid
with upstream flow accumulation and zeros elsewhere.
Grid: WEIGHT = merge (WEIGHTST, WEIGHT0)
A few more steps remained in the transfer of upstream flow accumulation
to the downstream basin. The next goal was to create a grid the same size and
shape as the downstream basin with values of 1 everywhere except the location of
the control point (where the value of upstream flow accumulation would be
88
located). This ?total weight? grid could then be used to calculate a new flow
accumulation grid for the downstream basin. Step one in this process was to
create the mask grid that contained a value of one at every cell in the downstream
basin. This task was performed by dividing the downstream flow direction grid
by itself.
Grid: MASK = FDRDS/FDRDS
With the mask created, the total weight grid was generated by merging the
MASK grid with the WEIGHT grid generated above.
Grid: TOTALWEIGHT = merge (WEIGHT, MASK)
Finally, the new downstream flow accumulation grid that included the
flow accumulation from the upstream area was computed by running the flow
accumulation function on the TOTALWEIGHT grid.
Grid: FACCDS =flowaccumulation(FDRDS,TOTALWEIGHT)
This process not only works for merging one upstream basin to one
downstream basin, but it can also be applied to situations where two or more
upstream basins are flowing into one downstream basin. To accomplish this task,
the first 4 steps are run on each of the upstream basins. Once completed, all
WEIGHT grids for the upstream basins must be merged together with the MASK
grid before calculating the downstream flow accumulation grid.
89
6.4 RESULTS FROM SECOND RUN
Although the processing time increased more than 10-fold, the
incorporation of 30-meter resolution DEMs was a vital step in producing accurate
drainage areas for the control points in the Guadalupe and San Antonio basins.
Clearly, the increased detail of the new dataset was able to more accurately
represent the drainage features of the landscape, as shown in Figure 6.4.
Figure 6.4: Comparison of 90m (left) and 30m(right) data images
Not only were the watersheds defined more precisely, but the fact that the
1:24,000 scale elevation data more closely fit the 1:100,000 scale stream network
eliminated most instances of short-circuiting in the basin. Also, the DEM, along
with the buffered streams, eliminated the problem of drainage area being captured
from outside the basin. Sections 6.41 and 6.42 detail the results of the Guadalupe
and San Antonio basin parameters, respectively.
90
6.4.1 Guadalupe Results
After generating the drainage areas for each of the control points in the
Guadalupe basin, the results were astounding. Table 6.3 shows how closely the
CRWR generated drainage areas matched the established USGS/HDR drainage
areas in the second run, as compared to those values found in the first run.
Point Version 2 Version 1 USGS HDR Version 2 Version 1
ID
Area (mi
2
) Area (mi
2
)
% Error
1 837.78 870.83 839 -0.15 3.79
2 1314.7 1353.13 1315 -0.02 2.90
3 1432.25 1471.73 1432 0.02 2.77
4 1519.03 1560.92 1518 0.07 2.83
5 129.54 136.37 130 -0.35 4.90
6 2103.07 2103.38 2103 0.00 0.02
7 93.85 94.13 94 -0.16 0.14
8 355.31 359.75 355 0.09 1.34
9 412.43 417.92 412 0.10 1.44
10 838.81 848.1 838 0.10 1.21
11 310.63 323.07 309 0.53 4.55
12 459.79 480.15 460 -0.05 4.38
13 549.05 593.68 549 0.01 8.14
14 4935 5078.28 4934 0.02 2.92
15 5195.88 5419.05 5198 -0.04 4.25
16 493.42 519.48 494 -0.12 5.16
38 10122 N/A 10128 -0.06 N/A
Table 6.3: Comparison of results from second run to established USGS/HDR values
The highlighted columns show the values found for the USGS/HDR
known flow locations and the percent error between the two, respectively.
Clearly, the results from the second run leave almost no room for improvement, at
least at the large, watershed scale. All drainage areas for gaged locations were
less than half a percent difference from their known values. In fact, not one of the
drainage areas shown differed from its established value by more than a few
91
square miles, even for watersheds as large as 5200 square miles. CP38 represents
the drainage area at the confluence of the Guadalupe and San Antonio basins. At
this point, the known drainage area is 10,128 square miles. CRWR reported an
area of 10,122 square miles, a mere 6 square mile difference. Overall, the results
for the USGS gage watersheds in the first run differed by an average of 3.15%.
After incorporating the 30-meter data, the difference over the same set of
watersheds was reduced to 0.11%.
6.4.2 San Antonio Results
The results from the second run on the San Antonio basin were nearly as
impressive as the Guadalupe results. Table 6.4 details these results.
Point Version 2 Version 1 USGS HDR Version 2 Version 1
ID
Area (mi
2
) Area (mi
2
)
% Error
17 8.19 7.75 8.3 -1.28 -6.63
18 44.11 46.79 41.8 5.53 11.94
19 136.04 140.36 137 -0.70 2.45
20 187.04 191.56 189 -1.04 1.35
21 633.63 639.42 634 -0.06 0.85
22 648.84 655.00 15.6 N/A N/A
23 648.84 655.00 650 -0.18 0.77
24 11.65 9.89 13.1 -11.07 -24.50
25 58.27 57.96 58.3 -0.05 -0.58
26 99.60 99.74 99.7 -0.10 0.04
27 961.51 975.54 967 -0.57 0.88
28 1310.35 1326.63 1317 -0.50 0.73
29 1737.49 1782.49 1743 -0.32 2.27
30 9.41 7.97 9.4 0.14 -15.21
31 64.55 65.43 65.4 -1.31 0.05
32 2107.81 2137.81 2113 -0.25 1.17
33 68.32 68.17 68.4 -0.12 -0.34
34 273.97 271.01 274 -0.01 -1.09
35 825.42 824.98 827 -0.19 -0.24
36 239.26 257.95 239 0.11 7.93
37 3906.02 3972.22 3921 -0.38 1.31
Table 6.4: Comparison of results from second run to established drainage areas.
92
Again, almost every value found for a USGS gage location fell within a
half of a percent of the established value. Even problematic points such as CP17,
18, 24,30, and 36 were drastically improved. In the first run, the average error
across the USGS gaged watersheds was 4%. After the second run, this error was
reduced to 1%, which is clearly sufficient when dealing with watersheds of this
size.
6.5 QUALITY CONTROL
Regardless of the accuracy found with respect to the USGS gage
watersheds, the true test of the dataset was its ability to accurately delineate the
smaller watersheds. Also, by proving the accuracy of both the large and small
watersheds, an assumption can be made that all watersheds in between will also
be relatively accurate. Therefore, the same quality control test described in
Chapter 4 was also performed on the results of the Guadalupe and San Antonio.
When performing the quality control on the 90-meter data, all watersheds
below a 1000 cell flow accumulation threshold were visually checked and
manually re-delineated if problems were found. At 90-meter resolution, a 1000
cell flow accumulation corresponds to a drainage area of approximately 3 square
miles, whereas the same number of cells corresponds to an area of approximately
0.3 square miles when using 30-meter data. It was first thought that an increase in
the cell threshold was appropriate when moving to 30-meter data since the
corresponding 1000 cell area was so small. However, with the success of the
USGS gage delineations, it was decided that the original 1000 cell threshold
might still hold true for the higher resolution data sets. To truly test the
93
assumption, each watershed below 1000 cells was delineated manually from the
DRG maps, instead of simply checking the watersheds visually. Table 6.5 is a
synopsis of the results from both the Guadalupe and San Antonio basins.
CP ID # of Cells
Area (mi
2
)QCArea(mi
2
)
61902105302 0 0.00 0.16
11903944301 55 0.02 0.69
11805371201 118 0.04 0.03
11805107301 168 0.05 0.05
61802036301 168 0.05 0.05
61802036002 168 0.05 0.05
11805107002 168 0.05 0.05
11804539001 171 0.06 0.05
11804539301 171 0.06 0.05
11905423303 218 0.07 0.06
11905423301 233 0.07 0.06
61803825302 271 0.09 0.09
11905423304 336 0.11 0.10
11905423001 336 0.11 0.10
11904510303 349 0.11 0.09
61803838301 360 0.12 0.11
61801967301 398 0.13 0.12
11805371101 571 0.18 0.16
11905423302 590 0.19 0.18
61801975001 674 0.22 0.21
61801975301 674 0.22 0.21
61801954002 796 0.26 0.25
61801954302 803 0.26 0.25
61902168001 804 0.26 0.28
11904510301 874 0.28 0.25
61902168301 957 0.31 0.31
Table 6.5: Comparison of computer and hand-delineated watersheds
As shown, even for watersheds as small as five hundredths of a square
mile, the 30-meter data was able to produce extremely accurate results. For the
26 watersheds delineated, only 2 differed by more than three hundredths of a
square mile (see highlighted points). The reason for the discrepancy in both
94
CP61902105302 and CP11903944301 was an error in the stream network. Both
points had been placed near the end of a stream that had not been digitized to the
full extent of its reach. Otherwise, the watershed delineation would have been
accurate. Therefore, as a result of this study, it was concluded that a simple visual
check of the watershed below the 1000 cell threshold is sufficient to evaluate the
quality of the results. Further analysis of the cell threshold issue can be found in
Chapter 8.
6.6 CONCLUSION
In conclusion, the incorporation of the 30-meter DEM into the established
methodology provided outstanding results. A complete list of result for each
control point in the Guadalupe and San Antonio basins can be found in Appendix
B and C, respectively. Nearly every value generated by CRWR matched
USGS/HDR values within an error of less than a half of a percent. These results
were shown to be significantly better than those obtained through the use of 90-
meter data. Not only did the 30-meter data provide accurate results for the large,
USGS watersheds, but the data also produced similar results for watersheds of a
few hundredths of a square mile. The ability to delineate watersheds over such a
wide range of areas (10,000 mi
2
?0.05mi
2
) is certainly a powerful advance in
water resource management.
The only drawbacks to the use of 30-meter data were the cumbersome file
sizes and the significant increase in basin processing time. Functions that ran for
1-2 hours with 90-meter data lasted for approximately 15 hours with 30-meter
data. The processing time is expected to increase significantly for larger basins,
95
making it almost impossible to perform the processing on a basin-wide scale.
However, a method for sub-dividing the basin into smaller, more manageable
sections was developed that should alleviate some of the problems anticipated for
larger basins.
96
CHAPTER 7: CASE STUDY ? SAN JACINTO BASIN
7.1 INTRODUCTION
The final basin studied in this research was the San Jacinto basin. The
basin is located in the southeastern portion of Texas and drains an area of
approximately 4000 square miles, including the City of Houston. The basin
contractor for the San Jacinto was Espey, Padden Consultants, Inc. Unlike the
previous 3 basins, the basin contractor for the San Jacinto required the full set of
parameters for each control point: drainage area, average curve number, average
precipitation and the next downstream control point. Since Espey was using
curve numbers and precipitation to distribute flows throughout the basin, the flow
length parameter was not required.
Due to the success found from using the 30-meter data, the process for the
San Jacinto was not run using 90-meter data. Therefore, instead of comparing
results from 2 separate runs on the basin, the main goal of this study was to judge
the ability of the 30-meter DEM to capture accurate drainage areas in a basin of
rather low relief. Also, a secondary goal was to streamline steps in the
methodology in order to compensate for the increase in processing time that result
from the use of 30-meter data. Areas with room for improvement were the manual
placement of control points on the stream network and the manual generation of a
table locating the next downstream point. Figure 7.1 shows the critical files used
in the basin processing: control points, stream network, and 30-meter DEM.
97
Figure 7.1: San Jacinto basin layout
7.2 BASIN PROCESSING
There were 426 control points for which parameters were needed. In
addition to the 204 water right/diversion points and 19 stream gage locations, a
few new point locations were incorporated into the basin study. Espey requested
the inclusion of 187 specified return flow locations and 19 water quality segment
endpoints. The return flow locations were delivered to CRWR as an Excel
98
spreadsheet with latitude and longitude coordinates, from which a point coverage
was created. The water quality segment endpoints were generated by TNRCC.
The stream network editing for the San Jacinto basin presented a different
set of problems compared to the previous 3 basins studied. Instead of the natural
stream channels encountered previously, the San Jacinto stream network included
many man-made channels and canals. Due to the flat landscape in the lower
portions of the basin, a well-defined stream network was absolutely crucial in
order to obtain quality results, even with the 30-meter DEM. Therefore, careful
consideration was taken in the editing process, particularly in the areas
surrounding control points and along the basin boundary.
The grid processing was performed entirely in Arc/Info. Since the DEM
was approximately 20 million cells in size, sub-dividing the grid was not
necessary. The processing time for the entire basin was approximately 10 hours.
Average curve number and precipitation grids were also generated in Arc/Info
using the commands listed in Chapter 4.
7.3 STREAMLINING THE METHODOLOGY
Other than the grid processing steps, the main time-consuming tasks in the
methodology were the stream editing, control point placement, and the generation
of the next downstream point table. There wasn?t much room for improvement
with regards to the stream editing since much of the work involves engineering
judgment on a case-by-case basis. However, the other two tasks are fairly direct
and can be automated. While this researcher performed the bulk of the data
99
development, a WAM team member, Hudgens (1999), developed a set of tools
that included steps to automate the two tasks.
7.3.1 Snapping the Control Points to the Network
As stated, the control points must be placed in the proper locations on the
flow accumulation grid in order to generate the final results. Therefore, not only
was there a need for a tool to snap the points to the network, but the points also
had to fall on the flow direction path. Hudgen?s script first generates a DEM-
derived stream network. This network is generated by tracing the least-cost path
on the flow direction grid from each headwater point in the single-line stream
network. The fact that the network is traced from the flow direction grid means
that each arc in the network falls in the middle of the flow accumulation cells, as
showninFigure7.2.
Figure 7.2: Comparison of DEM-derived stream network and single-line network.
100
With a stream network centered on the flow direction path, the next step in
Hudgen?s tools is to snap the control points to the newly created network. Since
the points are snapped to a network built from the FDR grid, all the points will be
on the proper flow accumulation grid cell. When the parameters are read, an
accurate drainage area will be reported. The DEM-derived network can take a
few hours to process, depending on the size of the network, but the snapping
portion is completed in minutes. The advent of this tool alone eliminated several
days of processing time.
7.3.2 Generating the Table of Downstream Control Points
Although the identification of the next downstream control point was an
original parameter needed in the WAM process, it was not required by the basin
contractor for the 3 previous basins in this study. Again, stream length values
were used as a substitute. However, the basin contractor for the San Jacinto
requested a complete set of control point parameters, including the next
downstream point. In earlier research performed by Hudgens, the downstream
control point table was generated manually by checking each point individually,
tracing the path downstream, and recording the next control point in an Excel
spreadsheet. Again, this process was tedious and required many man-hours.
Therefore, during the data development process of this basin, Hudgens worked to
create a tool to automate this process.
The first step was to ?Build the Stream Network Connectivity.? This
process assigned ID values to each arc in the DEM-derived stream network. Once
the arcs were labeled, the script located the next arc downstream. Finally, using
101
the snapped control points, the script was able to identify the corresponding arc
ID for the control point, and then navigated through the stream network until
reaching the next downstream point. The control point ID of the downstream
point was then copied into the attribute table of the snapped control points.
Finally, a diagram of control point connectivity was created, as shown in Figure
7.3.
Figure 7.3: Control point connectivity diagram
102
7.4 SAN JACINTO BASIN RESULTS
The changes in the methodology for the San Jacinto basin processing were
not made to improve the results of the basin parameters. Other than the two
changes described, the basin processing was performed in the same manner as the
Guadalupe and San Antonio basins. Although computing basin parameters was
the main goal, a study of the methodology?s effectiveness in dealing with areas of
low relief was also an important task. The following table (7.1) contains the
drainage area results for the stream gage locations in the San Jacinto basin. A
complete list of results for all control points in the basin can be found in
Appendix D.
Point CRWR USGS Difference Error
ID
mi
2
mi
2
mi
2
%
8067650 456.88 451 6 -1.30
8068000 828.71 828 1 -0.09
8068500 403.39 409 -6 1.37
8068740 131.33 131 0 -0.25
8069000 284.47 285 -1 0.19
8070000 324.52 325 0 0.15
8070500 105.58 105 1 -0.56
8071000 117.49 117 0 -0.42
8071500 2814.02 2800 14 -0.50
8073500 284.19 293 -9 3.01
8074000 343.45 358 -15 4.06
8074500 87.91 86 2 -1.86
8075000 93.24 95 -2 1.75
8075500 65.74 63 3 -4.35
8076000 64.07 69 -5 6.75
Table 7.1: Comparison of CRWR and USGS values for San Jacinto gages.
As shown, the drainage area results for the San Jacinto basin gages were
not quite as accurate as those generated for the Guadalupe and San Antonio basin.
103
Although most of the points fell at or below the 1% difference mark, the
highlighted gages reveal significant deviance from the established values.
The main reason thought to be behind these problems was the lack of
relief in the terrain. For example, the watershed slope for USGS gage 8076000
was 0.00075 m/m. Figure 7.4 shows the CRWR delineated watershed for this
gage. Notice the erratic nature of the watershed boundary. Even at the 1:24,000
scale, the resolution of the data was not sufficient enough to properly represent
the subtle changes in the landscape.
Figure 7.4: CP8076000 watershed diagram with circles denoting erratic features.
The boundary of this watershed was checked thoroughly against the DRG
maps, especially around the highlighted areas. Since the terrain was so flat, no
contours existed on the map to interpret if the computer delineation was correct.
104
The watershed boundary was so difficult to decipher from the maps that suspicion
about the USGS values became a factor. The USGS values were originally
developed through manual delineation from similar maps. Judgment by the
person who developed the USGS value could account for the 6.75% difference in
the CRWR watershed.
7.5 QUALITY CONTROL
Checking the quality of the small watersheds for the San Jacinto was also
somewhat difficult. Of the 30 points below the 1000 cell threshold, only 3 were
visibly incorrect and had to be delineated by hand. However, many of the tiny
watersheds were in marshy areas along the coast or fell completely between two
contour lines on the DRG. In such cases, there was no way to visually decipher
the ?true? drainage area for the point. Therefore, the drainage areas found
through the grid processing were assumed to be correct for those difficult points.
7.6 CONCLUSION
The processing of the San Jacinto represented a synthesis of knowledge
learned through the other case studies. For this basin, the buffered streams and
30-meter DEM were both used in an effort to generate the best possible results on
the first processing run. In addition, new tools were created for placing points and
generating the downstream control point table in order to offset the lengthy
processing time of the 30-meter DEM.
Although the best processing techniques were used, the results for the San
Jacinto basin clearly had some deficiencies. Unlike the points in the Guadalupe
and San Antonio basins, several of the control points in the San Jacinto had
105
drainage area differences above the 1-2% range. After studying the delineated
watersheds for these points, it was determined that the lack of terrain relief in the
basin contributed to the differences. The average slopes throughout the basin
(0.0012 m/m) were so small that even the 30-meter DEM could not accurately
represent small changes in the landscape. Further study on the slope limitations
will follow in Chapter 8.
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CHAPTER 8: RESULTS AND DISCUSSION
8.1 INTRODUCTION
One of the primary purposes of this research was to evaluate the effect of
changes in the methodology used to calculate watershed parameters for the
WAM. The previously established methodology used the interior single-line
stream network and a 90-meter DEM of each basin for the processing. The case
studies presented in Chapters 5-7 showed the advantages of adding exterior
streams within the basin buffer and the using 30-meter DEMs. This chapter
presents a synthesis of what was learned through these case studies and evaluates
the overall accuracy of the methodology.
8.2 IMPROVED RESULTS FROM THE USE OF 30-METER DEMS
90-meter DEMs were the only available datasets for use in processing
entire river basins at the start of the project. Therefore, the methodology
established at the beginning of this research utilized these data files. The first
runs of the Nueces, Guadalupe and San Antonio were all performed with 90-
meter DEMs, but failed to produce acceptable results. The average absolute
differences for the USGS gage locations in each basin were 2.22%, 3.17%, and
4.02%, respectively. Although the average differences seem relatively low,
distinct differences in the control point watersheds were prominent. Along with
the watershed errors, several instances of short-circuiting in the stream network
were also found. These problems were anticipated since the literature indicated
problems with using DEMs and stream networks of different scales.
107
In the early part of 1999, USGS released 30-meter data for the entire state
of Texas as part of the National Elevation Dataset (NED). The seamless dataset
produced improved results with its ability to more accurately represent the
features of the terrain, even in areas of low relief. A comparison of the results
found from the use of each dataset is shown in Figure 8.1.
Figure 8.1: Results from the use of 30m and 90m data in the San Antonio and Guadalupe basins
In the figure, the difference in drainage area between the USGS values and
CRWR values for the Guadalupe and San Antonio basins were plotted against
each other on a log/log scale. Results from the Nueces basin and San Jacinto
basin were not included since 30-meter data was not used on the Nueces and 90-
meter data was not used on the San Jacinto.
108
The fact that all the points fell well below the 1-to-1 line shows that the
use of 30-meter DEMs improved the drainage area results. The average percent
difference in drainage areas across both basins was 3.08% for the results
generated from 90-meter data while the 30-meter data produced an average
percent difference of 0.42% for the same control points. Using the 90-meter
DEMs, 22 of the control points had an absolute difference greater than 1% while
only 2 points remained above 1% after incorporating the 30-meter DEMs.
Further statistics on the data is shown in Table 8.1.
Statistic 90-meter 30-meter
Mean 3.08 0.42
Standard Deviation 2.75 1.05
Range 11.69 5.52
Minimum 0.24 0.01
Maximum 11.94 5.53
Table 8.1: Statistical summary of % difference in results for 90-meter and 30-meter data.
The use 30-meter DEMs improved the results on several levels. Not only
did the data improve results for the larger, USGS watersheds by more clearly
defining basin boundaries, but the data also improved intermediate watersheds by
eliminating virtually all instances of short-circuiting in the stream network.
Clearly, the fine scale DEM (1:24,000) more accurately matched the features of
the terrain and the 1:100,000 scale stream network. The effect of 30-meter data
on the small, quality control watersheds is shown later in this chapter.
The only drawback found from using 30-meter data was the significant
increase in both file size and processing time of the DEM. For example, the DEM
109
file size for the San Antonio increased from 2.2 MB to 43 MB, while the flow
accumulation grid increased from 27 MB to 239 MB. The DEM processing time
rose from approximately 1 hour to almost 15 hours. Dividing larger basin DEMs
into smaller parts at the beginning of the process, as described in Chapter 6, can
reduce the total processing time significantly. If file size or processing time is a
restriction, 90-meter DEMs can be used with buffered streams to produce
acceptable results, as shown in the next section.
8.3 USE OF BUFFERED STREAMS
For the first effort in processing the DEM for the Nueces basin, the
constructed stream network contained only the streams that fell within the
established basin boundary. However, the DEM was buffered a distance of 10
kilometers in order to allow the methodology to determine its own boundary from
the data itself. Upon checking the delineated watersheds from the first run, it was
clear that many watersheds meandered outside of the basin boundary. This
resulted in large differences for many of the drainage area values. Several
solutions were considered, including clipping the DEM to the original basin
boundary and building an artificial wall in the DEM along the basin boundary.
However, the solution decided upon was to ?burn? additional streams into the
basin buffer.
110
Figure 8.2: San Jacinto basin without (left) and with (right) buffered streams.
Intuitively, the results for control point watersheds within the interior of
the basin would not be affected by the use of buffered streams. However, the
addition of the streams would affect those control point watersheds that exist
jointly with the basin boundary. Drainage area results were generated with and
without buffered streams for the control points in the Nueces and San Antonio
basins. The results were plotted against each other on a log/log graph for
comparison with a 1-to-1 line, as shown in Figure 8.3.
111
Figure 8.3: Results from burning and not burning streams in the Nueces and San Antonio
Points falling below the line represent improvement in drainage area
difference by the use of buffered streams. As shown, the addition of the streams
within the buffered area provided a significant reduction in absolute drainage area
difference across the control point watersheds, with the average percent difference
dropping from 1.50% to 0.96%. Of course, the most significant improvement was
found for points whose watersheds were directly affected by changes in the basin
boundary. Watersheds in the interior portion of the basin fell along the 1-to-1
line, meaning the addition of buffered streams did not improve the results of these
points. A few of the points fell above the line, meaning a few watersheds actually
112
had worse results after adding streams. One possible explanation for this may be
that the USGS value used for comparison was wrong in the first place. So, when
the drainage area was reduced by the buffered streams, the percent difference in
drainage area became greater. Table 8.2 shows a statistical analysis of the results
for both scenarios.
Statistic W/O With
Mean 1.50 0.96
Standard Deviation 1.44 0.83
Range 7.87 2.81
Minimum 0.06 0.01
Maximum 7.93 2.82
Table 8.2: Statistical summary of difference in results for burning and not burning streams.
8.4 ANALYSIS OF DEGREE OF TERRAIN RELIEF
At the outset of this research, the literature reviewed stated the success of
automated terrain analysis techniques in areas with well-established drainage.
However, several authors expressed caution when using automated techniques in
areas of low relief, such as the coastal region of Texas. With the amount of
watersheds studied in this thesis, significant data existed to test the ability of both
90-meter and 30-meter data to accurately delineate watersheds for varying levels
of relief.
For both the Nueces and San Antonio basins, slopes were calculated for
each of the USGS gage watersheds using 90-meter data. Elevations were read
from the DEM at the upper and lower end of each watershed, and the flow length
for each was found using Arcview tools. The slopes were then plotted against the
113
absolute percent differences in the drainage area results to see if there was a
correlation between terrain slope and accuracy of results, as shown in Figure 8.4.
Figure8.4:Effectofslopeonabsolute%differenceindrainagearea(90m).
Clearly, there was no correlation between slope and absolute difference
for the 90-meter DEM results. The main reason for the lack of correlation is that
many factors besides slope affect the accuracy of the 90-meter DEM results.
Many differences can be contributed to short-circuiting and the lack of
cohesiveness between the 1:250,000 scale DEMs and 1:100,000 scale stream
network.
A similar study was also performed for results obtained from 30-meter
DEMs. Watershed slopes were calculated in the same manner for the Guadalupe,
114
San Antonio, and San Jacinto river basins. The addition of slope values from the
San Jacinto basin allowed for an insight into areas of particularly low relief.
Figure 8.5 is a summary of the results obtained from this analysis.
Figure8.5:Effectofslopeonabsolute%differenceindrainageareas(30m).
Figure 8.5 shows a clear correlation between slope and absolute drainage
area difference for 30-meter data. All watersheds with a slope greater than 0.002
m/m had an absolute difference less than or equal to 1%. However, once slopes
reached 0.002 m/m, a steep increase in absolute difference was apparent. A
majority of the slopes below this threshold were found in the coastal regions of
the San Jacinto basin, which has an overall basin slope of 0.00082 m/m. The
following table (8.3) contains statistical data on slope for the 4 basins studied.
115
The total area and basin slope represent values for each basin as a whole. The
average area and average slope represent values for the individually delineated
watersheds in the basin.
Basin
Total Area
(mi
2
)
Avg. Area
(mi
2
)
#of
Points
Basin
Slope
Avg.
Slope
Avg/Basin
Slope Ratio
Nueces 16749 3742 21 0.0016 0.0050 3.13
Guadalupe 5982 1342 14 0.0023 0.0034 1.48
San Antonio 4195 956 13 0.0026 0.0047 1.81
San Jacinto 3954 426 15 0.0008 0.0012 1.46
Average 7720 1617 16 0.0018 0.0036 1.97
Table 8.3: Representative slopes of the 4 basins within the study area.
As shown, the average slope of a delineated watershed is twice that of the
basin slope. Thus, most of the points within the basin still fall in areas with well-
defined drainage. With all 4 basins draining to the Texas coastline, the flattening
occurs only in the lower portion of the basin, which is where most of the drainage
area differences exist.
Further research was done to determine the threshold limit of distance
from the coast at which the problems with terrain slope occur. Figure 8.6 shows
that slopes below 0.002 m/m occur within 75 miles from the coast. Therefore,
although 30-meter DEMs produce accurate results for most cases, this study
reveals some limitations when working in areas of significantly low terrain relief.
116
Figure 8.6: Analysis of slope as a function of distance from coast.
8.5 QUALITY CONTROL
The final issue studied in this thesis was the effect of DEM resolution on
the quality control required for the datasets. At the outset of this research, a
threshold of 1000 cells was used as a benchmark for checking the smaller
watersheds in the basin. This cell count represents approximately 3 square miles
for 90-meter data and 0.3 square miles for 30-meter data. Therefore, all
watersheds below 3 square miles (or 0.3 square miles) were checked visually
against the DRGs for errors in watershed delineation. If errors were found, a new
watershed for that control point was delineated by hand from the DRGs. Since
the 1000 cell value was chosen somewhat arbitrarily, a study of its validity was
performed for this thesis.
117
For this study, error represents the absolute percent difference between the
computer generated value and the hand-delineated value. Upon studying the
results obtained from the 90-meter data in the Nueces, Guadalupe, and San
Antonio basins, approximately 60 watersheds below the 1000 cell threshold were
delineated manually. The results from this study have been plotted in Figure 8.7.
Figure 8.7: Plot of results from 90m DEM for small watersheds.
The general trend in the data shows an increase in error below
approximately 200 cells, which corresponds to an area of 0.6 square miles.
However, no clear conclusion can be made from this figure, especially since many
of the errors are above 25%. Inconsistency in the results can be attributed to the
lack of density in the 1:100,000 scale stream network. For example, when
118
comparing the stream network with the 1:24,000 scale DRGs, many small streams
necessary to define the watersheds were missing from the 1:100,000 scale
network. Also, many of the existing streams in the network ended without
continuing to the furthest extent of the matching streams shown on the DRG.
Often, these deficiencies were the cause of incorrect watershed delineation.
The same study described above was also performed on the results
generated from the 30-meter DEM. Twenty-five watersheds with a flow
accumulation of less than 1000 cells in the Guadalupe and San Antonio basins
were delineated manually and compared to the automated delineation. Since the
1000 cell threshold for 30-meter data corresponds to a much smaller drainage area
than that of the 90-meter data, it was anticipated that an increase in this threshold
would be required. Figure 8.8 shows the plot of results for the 30-meter data.
Figure 8.8: Plot of results from 30m DEM for small watersheds.
119
The results obtained from the study of 30-meter data revealed a clear
trend, with the error increasing for watersheds below approximately 400 cells or
0.15 square miles. From the graph, however, it is shown that the error does not
close to zero at 1000 cells. Ordinarily, this would suggest that drainage areas of
greater than 1000 cells should be checked until the percent error is eliminated.
However, in watersheds of this size, five percent error corresponds to a drainage
area difference of roughly 0.01 square miles. Clearly, the results show that the
30-meter DEM has the ability to more accurately read small changes in the
terrain.
As stated in Chapter 7, clear delineations could not be performed for the
small watersheds in the San Jacinto basin due to a lack of contours on the DRGs
in the flat areas. Therefore, without a clear basis for judging the accuracy of these
watersheds, the San Jacinto basin results were not included in the quality control
study.
8.6 CONCLUSION
The purpose of this research was to not only generate watershed
parameters, but also to study how changes in the methodology would affect the
results. The results showed that adding streams to the buffered area and
incorporating the use of 30-meter data had a profound effect on the calculated
parameters. Further discussion of the results and recommendations for future
work on this project follow in Chapter 9.
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CHAPTER 9: CONCLUSIONS AND RECOMMENDATIONS
This thesis analyzes an approach for calculating watershed parameters for
control point locations in State of Texas. GIS is used in the calculation of the
parameters, which are used as input into a water availability model, WRAP. First,
the EPA?s river reach file is edited to produce a single-line stream network for
each river basin in the study area. During the stream editing process, TNRCC and
the basin contractor build a control point coverage that includes water right, return
flow, water quality and USGS stream gage locations. Once the stream network
and control points are complete, a digital elevation model is built and processed
using CRWR-prepro. Next, average curve number and precipitation grids are
created. Then, watersheds for each control point are delineated from the
processed DEM, and the parameters are extracted from the flow accumulation,
CN, and precipitation grids. Finally, a script is run to locate the next downstream
point for each of the control points. The methodology was used to generate
results for 4 river basins in Texas: Nueces, Guadalupe, San Antonio, and San
Jacinto. Case studies were presented for each basin.
In each case study, changes in the methodology were made as problems
were encountered. For the Nueces, many of the watersheds along the outskirts of
the basin captured area from the adjacent basin. To remedy this problem, exterior
streams that fell within the 10km basin buffer were merged with the interior
stream network of the basin and burned into the DEM. The additional streams in
the buffer served to carry water away from the boundary and produced watersheds
121
that more accurately fit the established basin boundary. The average error in
drainage area across the basin was reduced from 1.5% to 0.96%. The most
improvement was found along the outer portion of the basin, while the interior
watersheds remained unchanged.
The Guadalupe and San Antonio basins were studied jointly since both
basins were processed simultaneously in the project time-line. Therefore, the
changes in methodology were applied to both at the same time. The first attempt
at generating watershed parameters was made using 90-meter DEMs (1:250,000
scale). Although complications were expected from using 1:250,000 DEMs with
1:100,000 scale river networks, the 90-meter DEMs were the best available data
source at the time. However, soon after the first run was completed, 30-meter
(1:24,000 scale) DEMs became available for the entire state as part of the
National Elevation Dataset (NED). Since many errors existed in the results
generated from 90-meter DEMs, the new 30-meter DEMs were incorporated into
the methodology and produced very accurate results. The average error in
drainage areas across the basin was reduced from 3.08% to 0.42%. The study
showed that the finer resolution DEMs were able to accurately delineate
watersheds of every size in the basin, ranging from approximately 10,000 square
miles to 0.15 square miles.
For the final case study, all the changes made in the Nueces, Guadalupe,
and San Antonio basins were applied to the processing of the San Jacinto basin.
In addition, newly created tools were used to automatically snap control points to
the stream network and to locate the next point downstream of each control point.
122
Also, since the San Jacinto is located in the coastal region of the state, an analysis
was made of the accuracy of the methodology in areas of low relief. Although no
correlation existed between slope and percent error with 90-meter data, it was
found that the use of 30-meter DEMs in the methodology produced accurate
results in areas with slopes above approximately 0.002 m/m, which generally
occur within 75 miles of the coast. Below that level of relief, confidence in the
results was questionable.
The quality control procedures for the methodology were also studied in
this research. When using 90-meter data, the flow accumulation grid has to be
checked for the existence of short-circuiting. Also, watersheds below a flow
accumulation of 1000 cells must be checked for errors in the automated
delineation. Many of the errors in small watersheds can be lessened by careful
construction of the stream network. However, when using 30-meter data, all
instances of short-circuiting were eliminated. Also, the study showed that the cell
threshold for checking watersheds could be reduced to approximately 400 cells,
which corresponds to a drainage area of 0.14 square miles.
Clearly, this study has shown that the accuracy of the methodology is
highly dependant on the source data used. However, after analyzing and changing
the methodology, a few limitations exist. The main limitation of using 30-meter
data is the significant increase in both file size and processing time, which each
increased more than 10-fold when compared to those for 90-meter data. The
study found that DEMs with less than 20 million cells are manageable. Those
larger should be sub-divided using the methods presented in Chapter 6. Also,
123
results from the San Jacinto indicated the possibility of limitations in areas of low
relief. With the inclusion of more coastal basins in the WAM project, more
studies on the effectiveness of the methodology in these areas must be made.
Since the coastal basins are relatively small compared to other basins in the state,
it may be possible to use 10-meter DEMs in these areas. A third limitation is the
lack of density in the RF3 files. By comparing the 1:100,000 scale river network
to the 1:24,000 scale DRGs, it is clear than many streams important to the
drainage features of the terrain are missing in the RF3. However, since the
completion of this research, EPA has released the National Hydrography Dataset
(NHD). Although the network is still at the 1:100,000 scale, it has been described
as a more complete and accurate stream network. Also, the Texas Water
Development Board is working on a 1:24,000 scale stream network for the state.
Upon completion, the incorporation of the 1:24,000 scale network should
eliminate many errors in the smaller watersheds, and should be helpful in defining
the drainage features of the flat, coastal basins.
124
APPENDIX A: NUECES BASIN RESULTS
125
A.1 INTRODUCTION
The following appendix contains a table of watershed parameters for all of
the control points in the Nueces River basin. The table includes the control point
identification number, type of control point, drainage area in square miles,
flowlength to outlet in miles, and the x and y coordinates of the control point
location based on the TSMS Albers projection described in Chapter 3.
126
ID Type Area (mi
2
) Flowlength (mi) X-coord. Y-coord.
1 Stream gage 757.35 368.23 1000279 806937
2 Stream gage 687.10 399.27 976890 812828
3 Stream gage 1863.16 333.81 1010296 773118
4 Stream gage 4045.47 260.92 1031068 703970
5 Stream gage 5193.11 218.54 1074304 695931
6 Stream gage 8144.20 139.44 1141375 683607
7 Stream gage 393.18 327.22 1028577 813632
8 Stream gage 124.32 330.62 1021156 815410
9 Stream gage 637.42 297.20 1031624 786619
10 Other primary 33.96 300.58 1021726 792426
12 Stream gage 208.49 309.74 1049103 814008
13 Stream gage 246.82 289.79 1050368 794439
15 Other primary 4.39 306.90 1054050 809233
16 Stream gage 45.19 305.20 1057745 823187
17 Stream gage 165.23 280.79 1068993 800752
18 Stream gage 97.42 308.87 1072852 822830
19 Stream gage 153.20 288.43 1082194 803040
21 Other primary 57.46 302.15 1089165 819406
22 Other primary 105.08 288.83 1084854 804956
24 Stream gage 138.99 285.79 1024928 776535
25 Stream gage 3428.13 218.59 1083474 730503
26 Stream gage 784.26 148.03 1142083 714461
27 Other primary 5478.07 112.59 1171812 703553
28 Stream gage 1148.67 123.17 1167579 718729
29 Stream gage 15460.55 101.80 1177579 698281
30 Stream gage 16542.09 50.55 1210240 654689
31 Stream gage 16720.74 18.80 1233645 637945
111 Other primary 8.53 301.03 1037201 805844
112 Other primary 23.24 301.58 1038747 806934
141 Other primary 15.64 301.39 1041980 808286
142 Other primary 2.39 301.96 1044418 808545
201 Other primary 1.81 295.58 1077078 808311
202 Other primary 10.19 287.88 1072485 808585
231 Other primary 33.36 286.83 1094630 807107
232 Other primary 13.52 288.87 1098448 807630
991 Confluence 4450.24 238.75 1052394 693798
992 Confluence 4045.47 261.00 1030928 704077
993 Confluence 4426.69 248.43 1044158 701838
127
994 Confluence 7985.91 155.91 1127661 670900
995 Confluence 8072.20 146.88 1134454 678406
996 Confluence 658.52 224.06 1077805 733896
997 Confluence 3575.37 204.74 1095442 717202
998 Confluence 4245.27 168.40 1124277 700117
999 Confluence 828.12 145.21 1145472 714107
9910 Confluence 1532.65 245.47 1074369 757739
9911 Confluence 435.51 274.25 1051143 777500
9912 Confluence 518.71 266.84 1089645 783029
9913 Confluence 128.59 287.95 1023008 778543
12103745001 Diversion point 62.46 297.73 1086836 815531
12103806001 Diversion point 61.53 299.96 1058293 816846
12103878001 Diversion point 70.54 360.82 1030339 848477
12103878002 Diversion point 11.94 361.77 1031326 849033
12103884001 Diversion point 155.28 206.50 1102604 764066
12103903001 Diversion point 3461.83 215.12 1087447 727851
12103910001 Diversion point 20.39 226.34 1085165 611184
12103910301 Other secondary 20.39 226.34 1085165 611184
12103913001 Diversion point 13.98 343.02 1001863 774081
12103913301 Other secondary 13.98 343.02 1001863 774081
12103914001 Diversion point 44.55 256.19 1061891 758511
12103919001 Diversion point 4.95 175.49 1115675 732515
12103954001 Diversion point 518.85 266.51 1090011 782657
12103957001 Diversion point 54.50 402.87 989671 843931
12103978001 Diversion point 41.81 416.96 1005485 852446
12103978002 Diversion point 40.22 417.19 1005748 852677
12103978003 Diversion point 1.51 417.12 1005553 852629
12103978004 Diversion point 1.38 417.22 1005400 852800
12103986001 Diversion point 24.51 216.78 1119644 780861
12103986002 Diversion point 1.08 217.26 1119973 780476
12103986301 Other secondary 1.08 217.26 1119973 780479
12103988001 Diversion point 6.64 292.25 1018085 780236
12103988002 Diversion point 6.54 292.69 1017733 780443
12103989001 Diversion point 6.61 292.32 1018056 780343
12103989002 Diversion point 6.58 292.58 1017826 780505
12103990001 Diversion point 14.51 291.88 1018475 780231
12103991001 Diversion point 3.14 292.96 1017378 780327
12103991401 Other secondary 0.01 292.74 1017647 780402
12104006001 Diversion point 60.74 409.04 989283 849215
12104008001 Diversion point 338.33 401.96 997014 844693
128
12104014310 Other secondary 3340.00 221.41 1080271 731506
12104041001 Diversion point 145.84 209.18 1102902 767682
12104094001 Diversion point 28.12 371.90 1023057 862329
12104113001 Diversion point 154.21 207.24 1102640 765108
12104169001 Diversion point 3.86 402.41 1006074 842193
12104169002 Diversion point 3.79 402.57 1006240 842067
12104169003 Diversion point 3.67 402.77 1006456 842215
12104169004 Diversion point 0.73 403.04 1006887 842239
12104169005 Diversion point 0.66 403.21 1007117 842168
12104169006 Diversion point 0.55 403.50 1007397 842128
12104169101 Other secondary 3.87 402.35 1005967 842212
12104169201 Other secondary 0.29 403.61 1007637 842186
12104177001 Diversion point 432.43 312.40 1033417 799429
12104238001 Diversion point 349.44 333.45 1026942 819787
12104238002 Diversion point 341.67 333.66 1026684 819923
12104238003 Diversion point 341.43 334.39 1026254 820830
12104278001 Diversion point 17.30 414.76 987694 853989
12104286001 Diversion point 51.56 220.99 1109895 779353
12104304001 Diversion point 129.04 287.74 1022991 778258
12104305001 Diversion point 431.42 312.93 1033539 800206
12104310001 Diversion point 246.42 264.34 1038144 753983
12104339001 Diversion point 242.71 267.35 1037122 757614
12104352001 Diversion point 34.07 318.05 1048278 822571
12104352002 Diversion point 33.61 318.24 1048190 822767
12104352003 Diversion point 33.48 318.42 1048078 823077
12104352004 Diversion point 33.37 318.61 1048007 823296
12104365001 Diversion point 12.05 409.90 975683 819658
12104402001 Diversion point 16540.85 51.13 1209473 654977
12104402501 Return flow 16540.85 51.13 1209472 654978
12104405001 Diversion point 0.21 393.32 998571 834853
12104413001 Diversion point 3.93 402.28 1005851 842124
12104505001 Diversion point 131.25 323.76 1045374 827463
12104505002 Diversion point 131.25 323.76 1045356 827471
12104506001 Diversion point 407.92 271.76 1091165 789110
12105009001 Diversion point 103.77 361.79 1021333 850876
12105009002 Diversion point 79.17 363.14 1021565 852384
12105063001 Diversion point 379.73 331.38 1028907 817715
12105063002 Diversion point 379.70 331.49 1028851 817889
12105065401 Other secondary 0.15 103.15 1177182 700585
12105145001 Diversion point 1.70 149.81 1145715 719692
129
12105145002 Diversion point 0.14 145.69 1148395 723560
12105170310 Other secondary 8.45 169.02 1114372 680838
12105186001 Diversion point 74.09 327.86 1045036 832342
12105192001 Diversion point 5.49 286.42 1075296 795872
12105201001 Diversion point 33.81 322.99 987589 713284
12105204001 Diversion point 61.66 332.20 1043365 837163
12105241001 Diversion point 379.75 331.27 1028904 817501
12105247001 Diversion point 163.66 203.59 1102369 760211
12105248001 Diversion point 165.89 202.96 1102148 759510
12105249001 Diversion point 166.32 202.35 1102069 758609
12105258001 Diversion point 1391.99 111.10 1175555 707885
12105297310 Diversion point 50.64 291.60 1021549 782579
12105304001 Diversion point 340.66 335.44 1026414 822254
12105305001 Diversion point 0.92 319.61 1053204 838548
12105325001 Diversion point 138.81 318.68 1047032 821942
12105344001 Diversion point 51.49 221.05 1109920 779447
12105344002 Diversion point 13.91 221.25 1109973 779669
12105372001 Diversion point 316.07 341.66 1024916 827786
12105398001 Diversion point 42.15 278.00 1054377 781066
12105398002 Diversion point 1.47 280.05 1056424 780750
12105398003 Diversion point 1.20 280.24 1056893 780895
12105420001 Diversion point 162.78 283.54 1088062 801165
12105420501 Return flow 162.95 283.47 1088109 801110
12105475001 Diversion point 2.70 338.13 1040415 843920
12105475002 Diversion point 1.78 339.44 1039322 844887
12105497001 Diversion point 385.59 329.16 1028683 815560
12105509001 Diversion point 12.70 17.70 1233662 639472
12105509002 Diversion point 11.79 18.52 1234926 639557
12105509003 Diversion point 8.53 19.22 1235965 639586
12105511001 Diversion point 0.02 136.94 1156036 729414
12105511002 Diversion point 0.37 138.85 1154226 730512
12105511003 Diversion point 0.73 136.95 1156492 729844
12105511004 Diversion point 0.60 136.82 1156319 729649
12105511301 Other secondary 0.02 136.94 1156034 729414
12105511501 Return flow 0.02 136.90 1156170 729404
12105511502 Return flow 2.82 138.41 1153759 729538
12105511503 Return flow 0.02 136.94 1156037 729414
12105561001 Diversion point 2.57 60.61 1211625 662175
12105575001 Diversion point 19.53 340.46 1040874 847406
12105575002 Diversion point 3.45 340.54 1040768 847495
130
62102464001 Diversion point 16720.74 18.80 1233644 637951
62102464002 Diversion point 16540.82 51.18 1209379 654970
62102465001 Diversion point 0.01 55.04 1217573 663322
62102465002 Diversion point 0.01 55.04 1217608 663376
62102465301 Other secondary 0.01 55.04 1217608 663376
62102466001 Diversion point 16719.37 20.39 1232529 635956
62102467001 Diversion point 16765.07 16.76 1234708 639109
62102467002 Diversion point 16764.77 17.29 1233802 639101
62102468001 Diversion point 16766.43 15.13 1235232 637046
62102468002 Diversion point 16765.96 15.57 1235212 637734
62102469001 Diversion point 16765.89 15.62 1235222 637806
62102469002 Diversion point 16766.39 15.19 1235217 637089
62102469002 Diversion point 16766.39 15.19 1235224 637081
62103016001 Diversion point 92.27 420.54 1002812 864437
62103016002 Diversion point 90.02 420.77 1002886 864707
62103017001 Diversion point 13.92 414.81 998837 859827
62103018001 Diversion point 16.92 419.42 1007641 851779
62103018002 Diversion point 16.92 419.42 1007568 851844
62103019001 Diversion point 0.10 415.36 1004365 851854
62103019002 Diversion point 42.12 416.33 1005589 851544
62103020001 Diversion point 62.72 410.05 1001182 852177
62103020002 Diversion point 61.07 410.91 1001674 853001
62103020003 Diversion point 52.32 413.34 1002493 851763
62103020004 Diversion point 52.19 413.72 1002808 851474
62103021001 Diversion point 62.79 409.97 1001124 852049
62103021002 Diversion point 63.24 409.71 1000779 851858
62103021003 Diversion point 64.51 408.69 999765 851185
62103021004 Diversion point 64.55 408.53 999693 851398
62103022001 Diversion point 0.05 405.31 998867 847866
62103022002 Diversion point 256.63 406.51 998307 849590
62103023001 Diversion point 324.33 405.57 998456 848231
62103024001 Diversion point 0.65 401.64 996821 844125
62103025001 Diversion point 3.40 404.60 1002261 845384
62103025002 Diversion point 2.80 404.94 1002732 845547
62103025003 Diversion point 2.67 405.15 1002999 845719
62103026001 Diversion point 4.18 404.07 1001630 845133
62103027310 Other secondary 4.57 403.79 1001179 844941
62103028001 Diversion point 7.83 402.59 1000349 843715
62103028002 Diversion point 7.70 402.77 1000606 843784
62103029001 Diversion point 358.14 397.66 997130 839442
131
62103034001 Diversion point 360.03 396.09 996714 837979
62103036001 Diversion point 360.58 395.46 997154 837201
62103037001 Diversion point 361.89 395.07 996917 836662
62103038001 Diversion point 29.20 413.84 988384 853115
62103039001 Diversion point 57.41 411.01 989995 851353
62103039002 Diversion point 57.06 411.27 990005 851759
62103039003 Diversion point 31.11 412.06 989360 852087
62103040001 Diversion point 63.35 407.63 990990 848316
62103040002 Diversion point 60.99 408.68 989615 848805
62103041001 Diversion point 63.35 407.63 990988 848317
62103041002 Diversion point 63.04 408.03 990477 848347
62103041003 Diversion point 60.99 408.68 989615 848805
62103042001 Diversion point 63.35 407.63 990987 848317
62103043001 Diversion point 73.24 403.75 991558 844197
62103043002 Diversion point 72.86 404.01 991521 844539
62103044001 Diversion point 43.84 405.99 986517 845998
62103044002 Diversion point 32.53 408.01 984393 845971
62103044003 Diversion point 5.05 409.02 983199 845839
62103046001 Diversion point 133.80 399.66 992268 840404
62103047001 Diversion point 0.95 407.47 989702 833341
62103048001 Diversion point 165.24 398.33 993288 838890
62103048002 Diversion point 165.17 398.41 993195 838980
62103049001 Diversion point 176.12 395.26 995681 836456
62103049002 Diversion point 176.67 394.84 996150 836071
62103049003 Diversion point 177.36 393.74 997457 835223
62103049004 Diversion point 579.03 390.60 997893 831909
62103050001 Diversion point 0.51 402.63 1007926 839186
62103051001 Diversion point 3.42 401.01 1006118 839835
62103052001 Diversion point 3.43 400.96 1006081 839835
62103053001 Diversion point 3.43 400.96 1006078 839836
62103054001 Diversion point 3.42 401.01 1006086 839835
62103055001 Diversion point 3.93 402.28 1005851 842124
62103055002 Diversion point 3.82 402.46 1006110 842170
62103056001 Diversion point 8.93 400.52 1004689 840060
62103057001 Diversion point 8.93 400.52 1004687 840070
62103058001 Diversion point 570.19 392.33 997910 833714
62103059001 Diversion point 576.91 391.54 997088 833019
62103060001 Diversion point 578.17 391.00 997587 832237
62103060002 Diversion point 577.06 391.28 997261 832710
62103061001 Diversion point 580.49 390.21 998145 831415
132
62103062001 Diversion point 608.51 388.51 999259 829465
62103063001 Diversion point 610.12 387.29 999051 827974
62103064001 Diversion point 610.29 387.14 999240 827830
62103065001 Diversion point 629.01 382.78 1000592 822403
62103066001 Diversion point 0.66 379.09 999026 818791
62103067001 Diversion point 766.59 365.16 999597 803275
62103068001 Diversion point 787.64 361.65 1001294 800075
62103069001 Diversion point 789.61 358.90 1003753 798142
62103070001 Diversion point 398.30 437.10 961681 840737
62103070002 Diversion point 383.11 438.52 962295 842204
62103071001 Diversion point 661.26 404.99 971779 816329
62103072001 Diversion point 1862.67 334.31 1010045 773806
62103072002 Diversion point 1859.62 334.49 1010100 774069
62103073001 Diversion point 1864.49 333.24 1010978 772573
62103074001 Diversion point 1901.13 322.86 1017123 762560
62103075001 Diversion point 1901.13 322.86 1017123 762560
62103076001 Diversion point 1901.13 322.86 1017123 762560
62103077001 Diversion point 1901.13 322.86 1017123 762560
62103078001 Diversion point 1901.13 322.86 1017123 762560
62103079001 Diversion point 1904.67 321.17 1018689 760710
62103080310 Other secondary 1984.47 313.30 1019595 752441
62103081001 Diversion point 2034.92 295.36 1020323 738864
62103081002 Diversion point 2034.18 296.42 1020691 739965
62103082001 Diversion point 1715.40 297.31 1021402 710532
62103082002 Diversion point 1622.33 293.81 1018612 713152
62103082003 Diversion point 14.86 272.76 1022461 715046
62103082004 Diversion point 33.37 281.48 1019950 725721
62103082005 Diversion point 32.98 281.99 1019841 726470
62103082006 Diversion point 32.69 282.51 1020163 727206
62103082007 Diversion point 0.81 282.27 1018634 726578
62103082008 Diversion point 0.38 283.20 1017667 727327
62103082009 Diversion point 0.03 283.75 1017331 728153
62103082010 Diversion point 2108.16 290.46 1016757 734858
62103082011 Diversion point 2108.16 290.46 1016756 734860
62103082310 Other secondary 12.16 274.90 1020722 717564
62103083001 Diversion point 2110.34 289.13 1016648 733270
62103084001 Diversion point 2122.02 286.69 1018728 731288
62103085101 Other secondary 2033.63 297.46 1020996 740811
62103085201 Other secondary 2032.24 298.55 1021121 741433
62103086001 Diversion point 2148.45 269.67 1023131 711075
133
62103086002 Diversion point 2147.65 270.69 1022582 712543
62103086003 Diversion point 2147.46 270.98 1022650 712948
62103086004 Diversion point 2146.65 271.77 1022300 713925
62103086005 Diversion point 1.59 270.53 1023621 712761
62103087301 Other secondary 7.14 345.38 995489 776522
62103087401 Other secondary 0.01 344.81 995814 775754
62103087601 Other secondary 0.00 345.25 995832 776323
62103088001 Diversion point 190.16 318.04 999627 744920
62103089001 Diversion point 408.81 308.34 998951 731499
62103089002 Diversion point 407.04 309.54 998045 732989
62103090310 Other secondary 1457.81 294.32 1013778 722439
62103091310 Other secondary 1457.81 294.32 1013779 722437
62103091311 Other secondary 1457.81 294.32 1013774 722448
62103092310 Other secondary 1457.81 294.32 1013780 722435
62103092311 Other secondary 1457.81 294.32 1013767 722448
62103092312 Other secondary 1457.81 294.32 1013761 722448
62103093001 Diversion point 1714.24 296.45 1020378 710567
62103094001 Diversion point 3866.24 268.74 1023610 710014
62103094002 Diversion point 1715.40 297.31 1021403 710532
62103095310 Other secondary 3871.07 266.36 1025501 707269
62103095311 Other secondary 8.30 268.82 1022360 706092
62103095312 Other secondary 7.59 269.34 1021961 706719
62103096001 Diversion point 3870.14 267.03 1024776 707991
62103096310 Other secondary 3871.07 266.36 1025491 707278
62103097310 Other secondary 3871.07 266.36 1025498 707271
62103097311 Other secondary 3871.07 266.36 1025493 707276
62103098001 Diversion point 7.46 269.42 1021876 706811
62103099001 Diversion point 12.94 275.51 1016754 698225
62103101301 Other secondary 3.40 274.32 1022279 693531
62103102001 Diversion point 68.93 251.51 1040779 701564
62103103001 Diversion point 15.47 255.91 1042112 680662
62103104001 Diversion point 4998.84 231.02 1061219 696784
62103105001 Diversion point 5104.04 230.27 1063020 697899
62103106001 Diversion point 5108.62 230.80 1063766 698119
62103106002 Diversion point 0.03 228.08 1064975 698059
62103106301 Other secondary 0.03 228.08 1064975 698059
62103107001 Diversion point 5120.88 225.38 1067721 696031
62103107002 Diversion point 5111.25 227.93 1065201 697878
62103108001 Diversion point 3.93 225.38 1067726 696032
62103109001 Diversion point 5115.41 228.13 1066200 697583
134
62103111001 Diversion point 5121.41 224.36 1068713 696723
62103112001 Diversion point 5145.94 223.88 1069185 696806
62103112002 Diversion point 5121.48 224.01 1069085 696821
62103114001 Diversion point 5149.50 222.17 1070824 697684
62103114002 Diversion point 5149.50 222.17 1070823 697682
62103114301 Other secondary 5149.50 222.17 1070822 697682
62103115001 Diversion point 5149.50 222.17 1070817 697666
62103116001 Diversion point 5149.50 222.17 1070818 697668
62103117001 Diversion point 5149.50 222.17 1070819 697671
62103118001 Diversion point 5197.26 217.43 1075132 694633
62103119001 Diversion point 5197.26 217.43 1075131 694637
62103120001 Diversion point 5197.26 217.43 1075132 694656
62103121001 Diversion point 5197.26 217.43 1075131 694655
62103122001 Diversion point 5197.26 217.43 1075131 694654
62103123001 Diversion point 5198.04 216.62 1076153 694187
62103123002 Diversion point 5197.26 217.43 1075130 694645
62103124001 Diversion point 5198.08 216.51 1076278 694192
62103125001 Diversion point 5216.72 215.76 1076716 694192
62103126001 Diversion point 5217.31 215.37 1076968 693700
62103127001 Diversion point 5217.63 214.95 1077138 693193
62103128001 Diversion point 5218.30 214.30 1077806 692704
62103128002 Diversion point 5218.30 214.30 1077804 692703
62103129001 Diversion point 5218.30 214.30 1077806 692704
62103130001 Diversion point 5243.59 214.01 1077995 692363
62103131001 Diversion point 5244.60 212.98 1078014 691046
62103132001 Diversion point 5246.04 211.44 1079573 689951
62103132002 Diversion point 5245.16 211.99 1079011 690006
62103132003 Diversion point 13.13 212.24 1078692 689774
62103133001 Diversion point 5281.21 208.76 1082040 687224
62103133002 Diversion point 5268.00 209.63 1081099 688211
62103133003 Diversion point 5267.84 209.76 1081004 688372
62103134001 Diversion point 5268.69 209.11 1081673 687701
62103135001 Diversion point 5284.38 208.36 1081929 685597
62103135002 Diversion point 5282.87 208.59 1082062 685881
62103135003 Diversion point 5282.82 208.77 1082263 685954
62103135004 Diversion point 5281.38 208.23 1082728 686900
62103135005 Diversion point 12.33 208.49 1082697 687034
62103135006 Diversion point 5281.30 208.55 1082431 687023
62103136001 Diversion point 5281.64 208.10 1082805 686889
62103136002 Diversion point 12.33 208.49 1082696 687038
135
62103137001 Diversion point 5281.64 208.10 1082809 686885
62103138001 Diversion point 5282.25 207.66 1083103 686288
62103138002 Diversion point 5281.92 207.74 1083002 686390
62103139310 Other secondary 5284.66 204.83 1085590 684338
62103139311 Other secondary 8.69 205.39 1084263 682187
62103140001 Diversion point 5389.00 196.44 1091319 674937
62103141001 Diversion point 0.36 156.33 1128256 670308
62103142001 Diversion point 7988.74 154.19 1128757 672539
62103143001 Diversion point 8096.68 143.89 1137007 680776
62103143002 Diversion point 8074.06 145.23 1135865 679678
62103144310 Other secondary 8466.27 119.19 1161979 692476
62103145001 Diversion point 21.09 371.29 1020292 860914
62103145002 Diversion point 23.36 370.39 1021092 860415
62103145003 Diversion point 24.04 369.58 1021502 859764
62103145004 Diversion point 34.14 369.03 1022198 859314
62103145301 Other secondary 21.09 371.29 1020292 860915
62103145302 Other secondary 23.36 370.39 1021092 860416
62103145303 Other secondary 24.04 369.58 1021501 859764
62103145304 Other secondary 28.97 370.71 1022869 861258
62103145305 Other secondary 34.14 369.03 1022199 859314
62103146001 Diversion point 60.24 367.67 1022832 857571
62103147001 Diversion point 137.49 354.23 1023682 842252
62103148001 Diversion point 38.14 367.42 1032793 854155
62103148002 Diversion point 38.14 367.42 1032793 854155
62103148003 Diversion point 36.70 368.68 1032059 855299
62103148004 Diversion point 35.81 369.10 1032173 855722
62103148005 Diversion point 35.81 369.10 1032176 855724
62103148301 Other secondary 40.19 365.61 1031658 853182
62103148302 Other secondary 39.67 366.92 1032122 853856
62103148303 Other secondary 1.12 367.05 1032191 854028
62103148304 Other secondary 38.17 367.34 1032739 854031
62103148305 Other secondary 38.14 367.42 1032796 854160
62103148306 Other secondary 36.97 368.02 1032981 854958
62103148307 Other secondary 36.70 368.68 1032061 855300
62103148308 Other secondary 35.81 369.10 1032171 855722
62103148501 Return flow 38.14 367.42 1032796 854160
62103149001 Diversion point 57.25 361.65 1031029 849400
62103150001 Diversion point 73.21 359.31 1028640 847186
62103150002 Diversion point 73.11 359.50 1028760 847414
62103151001 Diversion point 79.82 357.55 1027577 844933
136
62103151002 Diversion point 79.63 357.75 1027712 845193
62103151003 Diversion point 73.94 358.67 1028590 846134
62103152001 Diversion point 84.91 357.04 1027403 844362
62103153001 Diversion point 235.34 352.93 1024311 840640
62103153002 Diversion point 235.21 353.24 1024106 841070
62103153003 Diversion point 0.43 353.17 1024443 840838
62103154001 Diversion point 0.65 351.78 1023480 839629
62103155001 Diversion point 237.85 351.52 1023474 839343
62103155002 Diversion point 237.82 351.76 1023560 839499
62103156001 Diversion point 241.95 349.37 1023970 836585
62103156002 Diversion point 241.88 349.50 1024068 836661
62103157001 Diversion point 266.78 347.48 1024852 834340
62103157002 Diversion point 266.52 347.72 1024810 834688
62103157003 Diversion point 266.45 347.85 1024696 834887
62103158001 Diversion point 266.52 347.72 1024828 834660
62103158501 Return flow 316.09 341.43 1025042 827594
62103158502 Return flow 305.61 343.18 1024508 828601
62103159001 Diversion point 267.40 347.40 1024837 834238
62103160001 Diversion point 268.27 346.74 1024710 833300
62103160002 Diversion point 268.05 347.03 1024625 833753
62103161001 Diversion point 14.07 350.12 1026983 836857
62103161002 Diversion point 12.19 350.59 1027089 837422
62103162001 Diversion point 2.85 345.71 1021083 830072
62103163001 Diversion point 316.34 341.12 1025153 827221
62103164001 Diversion point 322.99 337.76 1026063 823702
62103165001 Diversion point 339.95 335.86 1027094 822417
62103166001 Diversion point 351.05 332.55 1027726 818890
62103167001 Diversion point 351.06 332.50 1027727 818836
62103168001 Diversion point 385.86 329.05 1028650 815521
62103169001 Diversion point 391.58 328.22 1027885 814602
62103170001 Diversion point 393.20 327.17 1028710 813614
62103171001 Diversion point 397.23 326.44 1029565 813023
62103171002 Diversion point 396.64 326.78 1029201 813304
62103172001 Diversion point 430.88 313.66 1033652 801350
62103173001 Diversion point 433.08 311.61 1033058 798348
62103173002 Diversion point 442.14 309.99 1034113 796899
62103174001 Diversion point 102.98 333.57 1018225 815000
62103175001 Diversion point 102.98 333.57 1018227 815019
62103176001 Diversion point 3.40 343.51 1040467 850454
62103176002 Diversion point 2.77 344.11 1040001 851221
137
62103176003 Diversion point 2.69 344.43 1039622 851056
62103177001 Diversion point 34.54 335.98 1043013 842119
62103178001 Diversion point 55.60 334.70 1043613 840404
62103179001 Diversion point 64.11 330.12 1043589 834621
62103179310 Other secondary 63.27 331.14 1043437 835985
62103180001 Diversion point 1.79 336.07 1036519 839267
62103181001 Diversion point 45.92 324.65 1044687 828538
62103181002 Diversion point 45.64 325.23 1044101 828956
62103181003 Diversion point 44.07 325.61 1043664 829373
62103182001 Diversion point 246.68 290.19 1049949 794747
62103184001 Diversion point 3.98 320.70 1064648 832197
62103184002 Diversion point 3.61 321.08 1064335 831729
62103185001 Diversion point 1.81 322.27 1065165 838325
62103186001 Diversion point 8.48 319.41 1067545 835496
62103186002 Diversion point 8.38 319.67 1067182 835629
62103186310 Other secondary 8.54 319.28 1067615 835304
62103187001 Diversion point 8.67 318.82 1067935 834883
62103187002 Diversion point 8.64 318.95 1067915 835081
62103188001 Diversion point 64.55 314.09 1071275 829561
62103189001 Diversion point 383.88 277.27 1091866 795288
62103190001 Diversion point 407.75 272.08 1091598 789176
62103190002 Diversion point 407.34 272.45 1092090 789340
62103190003 Diversion point 407.27 272.63 1092220 789649
62103190401 Other secondary 0.13 272.77 1092323 789683
62103191001 Diversion point 187.83 271.48 1068882 790718
62103192001 Diversion point 10.08 288.07 1072369 808825
62103193001 Diversion point 3428.10 218.67 1083407 730569
62103194001 Diversion point 30.84 291.58 1019453 780306
62103194002 Diversion point 14.67 291.54 1018866 779972
62103195001 Diversion point 129.04 287.74 1022989 778251
62103196001 Diversion point 137.72 286.55 1024086 777119
62103196002 Diversion point 137.31 286.70 1023958 777275
62103197001 Diversion point 173.08 277.79 1033151 769583
62103197002 Diversion point 170.55 279.12 1031900 770498
62103197003 Diversion point 170.46 279.33 1031939 770771
62103197004 Diversion point 170.34 279.46 1031773 770853
62103198001 Diversion point 235.16 269.80 1036851 760566
62103199310 Other secondary 4.51 227.09 1076272 730800
62103200001 Diversion point 39.25 210.15 1090468 719982
62103200002 Diversion point 38.33 211.30 1089164 720713
138
62103201001 Diversion point 3687.12 191.52 1104403 707437
62103201002 Diversion point 3687.12 191.52 1104403 707440
62103201003 Diversion point 3686.20 192.08 1104578 708145
62103201004 Diversion point 3686.20 192.08 1104586 708150
62103201005 Diversion point 3685.78 192.49 1105013 708629
62103201006 Diversion point 3685.78 192.49 1105012 708630
62103203001 Diversion point 4098.89 179.17 1112057 700384
62103203310 Other secondary 0.06 180.07 1112566 700523
62103204001 Diversion point 4464.19 144.27 1145172 702280
62103204002 Diversion point 4463.81 144.43 1144735 702230
62103204003 Diversion point 4463.58 144.86 1144305 702027
62103205001 Diversion point 4464.28 143.92 1145442 702444
62103205002 Diversion point 4464.24 144.03 1145328 702377
62103205003 Diversion point 4463.70 144.59 1144599 702180
62103206001 Diversion point 4477.23 142.67 1147094 702418
62103206002 Diversion point 7.17 143.05 1146731 702210
62103206003 Diversion point 4469.81 143.12 1146360 702524
62103207001 Diversion point 29.30 225.94 1109305 786168
62103208310 Other secondary 0.89 213.53 1106547 769704
62103209001 Diversion point 79.31 211.14 1104368 769505
62103210001 Diversion point 146.98 207.88 1102528 765910
62103210310 Other secondary 4.29 208.14 1102294 766003
62103211310 Other secondary 155.29 206.39 1102652 763951
62103211311 Other secondary 155.29 206.39 1102650 763955
62103212001 Diversion point 3.12 205.49 1091565 751873
62103212002 Diversion point 1.87 206.60 1091535 753337
62103213001 Diversion point 0.25 156.25 1138643 721936
62103214001 Diversion point 5478.07 112.59 1171815 703554
62103215001 Diversion point 6905.55 105.17 1177047 701070
62103215002 Diversion point 6889.58 107.77 1176484 703728
62103216001 Diversion point 327.45 172.50 1147371 758442
62103216301 Other secondary 327.45 172.50 1147367 758450
62103217001 Diversion point 460.98 164.60 1154135 755172
62103217002 Diversion point 458.77 164.86 1153927 755507
62103218001 Diversion point 486.23 159.66 1156357 751680
62103219001 Diversion point 499.58 154.22 1159580 749158
62104772001 Diversion point 7.23 174.40 1143764 754384
62104772301 Other secondary 7.23 174.40 1143762 754384
62108034401 Other secondary 0.00 172.56 1147253 758451
139
APPENDIX B: GUADALUPE BASIN RESULTS
140
B.1 INTRODUCTION
The following appendix contains a table of watershed parameters for all of
the control points in the Guadalupe River basin. The table includes the control
point identification number, type of control point, drainage area in square miles,
flowlength to outlet in miles, and the x and y coordinates of the control point
location based on the TSMS Albers projection described in Chapter 3.
141
ID Type Area (mi
2
) Flowlength (mi) X-coord. Y-coord.
1 Stream gage 837.78 402.01 1106216 867086
2 Stream gage 1314.70 330.75 1155876 856044
3 Stream gage 1432.25 302.41 1173844 857275
4 Stream gage 1519.03 278.36 1182551 840347
5 Stream gage 129.54 278.06 1181422 839306
6 Other primary 2103.07 176.84 1245044 815594
8 Stream gage 355.31 277.26 1184093 871281
9 Stream gage 412.43 257.96 1201351 869998
10 Stream gage 838.81 208.07 1227016 835698
11 Stream gage 310.63 206.29 1231462 839520
12 Stream gage 459.79 153.74 1259823 815096
13 Stream gage 549.05 125.21 1247601 786093
14 Stream gage 4935.00 100.48 1260471 769802
15 Stream gage 5195.88 50.08 1291215 740309
16 Stream gage 493.42 51.11 1276506 732321
38 Stream gage 10122.30 15.87 1304617 708825
45 Other primary 1660.55 270.84 1186324 836693
71 Other primary 43.27 252.75 1197898 861902
72 Other primary 33.98 252.55 1195292 857921
73 Other primary 12.38 250.80 1188131 851769
74 Other primary 4.22 270.68 1185572 847215
901 Confluence 862.23 398.57 1109070 867308
902 Confluence 910.46 395.38 1111595 868969
903 Confluence 972.66 385.33 1118720 865105
904 Confluence 1049.01 380.02 1123591 866348
905 Confluence 1088.23 367.56 1128049 859469
906 Confluence 1085.94 368.97 1128264 861240
907 Confluence 1368.82 311.76 1163954 859419
908 Confluence 12.00 305.61 1170093 858240
909 Confluence 382.99 269.09 1191954 871540
910 Confluence 1434.74 301.70 1174214 857427
911 Confluence 531.20 246.15 1201186 856674
912 Confluence 538.45 243.20 1204550 856881
913 Confluence 1736.78 255.23 1192539 822006
914 Confluence 1800.80 245.22 1200165 820929
915 Confluence 1870.64 243.91 1201808 821261
916 Confluence 382.94 202.61 1231150 835731
917 Confluence 3506.00 160.89 1251414 811560
142
918 Confluence 5188.95 55.78 1290567 744243
919 Confluence 613.20 221.22 1216103 840704
920 Confluence 1267.17 339.23 1147175 858686
921 Confluence 1351.65 318.23 1160445 862151
922 Confluence 1450.91 297.33 1177709 856570
11803747301 Other secondary 8.30 245.28 1209647 872661
11803747302 Other secondary 7.21 246.02 1209867 873843
11803769001 Diversion point 486.35 428.53 1080393 876638
11803769301 Other secondary 486.35 428.53 1080397 876633
11803825301 Other secondary 3.39 427.97 1080880 857045
11803846301 Other secondary 8.46 427.34 1080722 859590
11803857001 Diversion point 839.01 207.79 1227083 835184
11803859001 Diversion point 813.94 213.05 1222532 836034
11803895001 Diversion point 5813.07 30.44 1296511 724283
11803895401 Other secondary 0.00 27.20 1299622 725653
11803895501 Return flow 3.44 25.55 1297737 724217
11803896001 Diversion point 3.47 430.82 1086296 879890
11803896301 Other secondary 3.47 430.82 1086294 879892
11803899301 Other secondary 1.21 290.78 1174355 871511
11803904301 Other secondary 9.86 427.92 1084471 876708
11803904302 Other secondary 9.59 428.15 1084674 877025
11803916001 Diversion point 845.05 203.97 1229290 832976
11803960001 Diversion point 11.39 329.65 1141794 880065
11803960301 Other secondary 11.39 329.65 1141793 880064
11803973001 Diversion point 1873.10 241.94 1204065 821131
11803995101 Other secondary 11.83 202.61 1231081 835690
11803995201 Other secondary 9.74 203.66 1229896 836381
11804007301 Other secondary 3.88 415.76 1095018 859653
11804020001 Diversion point 5092.99 70.31 1277896 753844
11804022101 Other secondary 584.08 229.71 1211710 846793
11804022201 Other secondary 583.15 230.78 1211680 847867
11804027001 Diversion point 420.48 255.94 1201576 867930
11804033001 Diversion point 582.58 231.87 1210954 848552
11804033002 Diversion point 581.90 232.26 1210556 849134
11804034001 Diversion point 66.33 446.44 1062307 887731
11804034002 Diversion point 66.20 446.52 1062165 888028
11804034301 Other secondary 66.33 446.44 1062304 887734
11804034302 Other secondary 66.20 446.52 1062164 888030
11804043101 Other secondary 541.64 239.86 1207522 854959
11804043201 Other secondary 541.36 240.46 1206855 855028
143
11804062001 Diversion point 5115.62 64.86 1282799 749723
11804075001 Diversion point 2103.32 176.17 1245374 816288
11804080001 Diversion point 582.19 232.21 1210643 849147
11804089001 Diversion point 3463.06 174.51 1245074 817495
11804106001 Diversion point 1186.63 342.50 1145889 857597
11804110001 Diversion point 586.47 227.06 1213077 845746
11804114001 Diversion point 17.22 278.63 1181245 839876
11804114501 Return flow 17.13 279.07 1180758 839875
11804182001 Diversion point 5093.58 68.66 1278793 751835
11804182002 Diversion point 5093.54 68.79 1278848 752079
11804223001 Diversion point 62.54 446.98 1062040 888632
11804223301 Other secondary 62.54 446.98 1062033 888642
11804223401 Other secondary 0.02 447.27 1061777 888761
11804230301 Other secondary 1.64 302.24 1174186 858093
11804230302 Other secondary 1.56 302.56 1174172 858556
11804230303 Other secondary 1.47 302.82 1174291 858871
11804230307 Other secondary 1.30 302.92 1174334 859076
11804230308 Other secondary 0.73 303.51 1174117 859950
11804247301 Other secondary 109.58 319.66 1152160 882187
11804298001 Diversion point 11.63 431.88 1081583 881539
11804298301 Other secondary 11.63 431.88 1081584 881536
11804302301 Other secondary 26.25 313.06 1153513 871706
11804308301 Other secondary 580.60 233.80 1209346 848242
11804318001 Diversion point 4216.27 104.44 1259707 773839
11804324301 Other secondary 41.31 57.48 1291274 746216
11804373001 Diversion point 756.96 220.63 1216595 841144
11804373002 Diversion point 143.36 221.99 1215441 840556
11804373003 Diversion point 613.16 221.37 1215922 840865
11804373004 Diversion point 612.84 222.09 1215793 841667
11804373005 Diversion point 612.78 222.36 1216143 841763
11804388301 Other secondary 4.10 275.14 1187619 875750
11804426301 Other secondary 3.86 247.14 1209244 875294
11804441001 Diversion point 5083.86 73.01 1276776 757378
11804445501 Return flow 1432.27 301.83 1174114 857395
11804486001 Diversion point 55.92 405.80 1102725 869007
11804491001 Diversion point 11.71 320.20 1158335 861888
11804491002 Diversion point 10.92 321.57 1157184 862530
11804491003 Diversion point 8.10 322.62 1156833 863123
11804491301 Other secondary 11.45 320.38 1158153 862013
11804491302 Other secondary 11.09 320.96 1157757 862542
144
11804491303 Other secondary 11.03 321.31 1157495 862344
11804492001 Diversion point 541.79 239.63 1207756 854663
11804492301 Other secondary 541.79 239.63 1207755 854664
11804492501 Return flow 541.79 239.63 1207756 854662
11804502001 Diversion point 582.75 231.27 1210980 847976
11804502501 Return flow 583.67 230.15 1211302 847373
11804518001 Diversion point 310.64 206.34 1231486 839477
11804539001 Diversion point 0.05 162.73 1250279 810735
11804539301 Other secondary 0.05 162.73 1250279 810735
11804569101 Other secondary 612.47 222.89 1216126 842359
11804569201 Other secondary 612.24 223.41 1215454 842644
11804586001 Diversion point 10127.73 11.11 1309071 704482
11804586401 Other secondary 0.00 10.45 1309559 703649
11804586501 Return flow 2.86 9.46 1309724 704124
11804590001 Diversion point 982.88 380.96 1123065 865593
11804597101 Other secondary 784.12 216.55 1219664 837784
11804597201 Other secondary 783.78 217.04 1218901 838283
11804598101 Other secondary 841.53 400.96 1107223 867539
11804598201 Other secondary 839.62 401.23 1106853 867597
11804607001 Diversion point 1336.16 318.50 1160662 861820
11805006101 Other secondary 5031.36 84.62 1273765 765385
11805006201 Other secondary 5030.83 85.35 1273895 766504
11805012001 Diversion point 2.45 18.56 1301113 709252
11805012501 Return flow 2.51 18.30 1301399 708984
11805036001 Diversion point 1325.32 183.99 1239361 822901
11805036401 Other secondary 0.00 184.34 1239223 822658
11805037101 Other secondary 861.64 201.19 1231379 832370
11805037201 Other secondary 845.14 203.65 1229601 833189
11805038001 Diversion point 1301.96 192.17 1235680 826202
11805060001 Diversion point 11.03 440.76 1068738 884389
11805060301 Other secondary 11.03 440.71 1068727 884392
11805092001 Diversion point 583.15 230.72 1211619 847894
11805107001 Diversion point 2.63 403.43 1105231 865862
11805107002 Diversion point 0.05 405.58 1106132 863662
11805107301 Other secondary 0.05 405.58 1106130 863661
11805121001 Diversion point 58.07 239.99 1196675 844658
11805121401 Other secondary 0.00 240.04 1196662 844578
11805122001 Diversion point 641.99 416.12 1091300 864725
11805122401 Other secondary 0.10 416.60 1091424 864079
11805125001 Diversion point 42.28 344.41 1142961 862454
145
11805208001 Diversion point 48.13 414.07 1093940 863455
11805234001 Diversion point 814.39 212.30 1223321 836352
11805234002 Diversion point 815.08 211.42 1224102 835389
11805234003 Diversion point 815.09 211.24 1224230 835424
11805234004 Diversion point 817.45 210.37 1225044 835609
11805234005 Diversion point 838.04 209.34 1225932 835962
11805240001 Diversion point 783.77 217.04 1218886 838292
11805240401 Other secondary 0.01 217.99 1218036 837778
11805267001 Diversion point 461.15 152.70 1259720 813880
11805267301 Other secondary 461.15 152.70 1259720 813879
11805294301 Other secondary 26.34 92.92 1242703 760109
11805294302 Other secondary 26.38 92.79 1242755 759945
11805315301 Other secondary 5.86 431.51 1081933 881358
11805315302 Other secondary 5.86 431.51 1081942 881353
11805315303 Other secondary 5.44 431.86 1082465 881457
11805315304 Other secondary 5.38 431.97 1082488 881617
11805315305 Other secondary 5.32 432.33 1082855 881784
11805321001 Diversion point 23.47 382.53 1124629 869419
11805322301 Other secondary 11.73 440.11 1068470 883578
11805331001 Diversion point 91.25 444.77 1061615 874851
11805331301 Other secondary 91.25 444.77 1061615 874851
11805348001 Diversion point 128.39 449.70 1055669 876753
11805352001 Diversion point 95.32 443.58 1062717 875676
11805371101 Other secondary 0.16 292.31 1173113 881567
11805371201 Other secondary 0.03 292.49 1173013 881869
11805376001 Diversion point 42.45 56.59 1290983 745053
11805376301 Other secondary 42.45 56.59 1290979 745051
11805376302 Other secondary 42.59 56.28 1290432 744932
11805381001 Diversion point 10146.60 7.61 1312198 700695
11805381401 Other secondary 0.00 7.72 1312215 701033
11805394001 Diversion point 486.35 428.53 1080391 876641
11805401301 Other secondary 15.46 432.97 1075124 868598
11805401302 Other secondary 15.40 433.05 1075082 868777
11805402301 Other secondary 25.29 431.70 1075327 867434
11805424301 Other secondary 4.34 59.13 1291241 748546
11805426001 Diversion point 67.24 300.11 1167065 874992
11805444001 Diversion point 451.49 431.59 1076512 878284
11805466001 Diversion point 5190.45 53.38 1289968 742394
11805466401 Other secondary 0.00 52.75 1291192 742698
11805474001 Diversion point 923.98 387.82 1116742 866863
146
11805474002 Diversion point 930.22 385.92 1118019 865709
11805479001 Diversion point 715.34 410.56 1097665 863853
11805489001 Diversion point 2.04 19.24 1300179 709577
11805489002 Diversion point 0.83 21.83 1299003 710384
11805489101 Other secondary 9.24 21.08 1298771 711394
11805489201 Other secondary 58.57 20.85 1298991 711688
11805489401 Other secondary 0.00 22.13 1299845 710789
11805490001 Diversion point 923.22 388.54 1116060 866428
11805495301 Other secondary 66.38 450.45 1058193 871039
11805501001 Diversion point 5.77 402.75 1108549 872068
11805521001 Diversion point 484.92 429.10 1079788 877300
11805528101 Other secondary 842.10 400.12 1107926 866475
11805528201 Other secondary 841.76 400.63 1107513 867111
11805531001 Diversion point 561.77 420.21 1087360 868116
11805534001 Diversion point 923.31 388.36 1116158 866492
11805536001 Diversion point 709.77 411.18 1096832 864337
11805541001 Diversion point 188.13 441.87 1063127 879530
11805545001 Diversion point 1.78 302.67 1166493 883647
11805556001 Diversion point 122.73 316.28 1156182 881160
61801930001 Diversion point 20.99 458.70 1047429 876945
61801930301 Other secondary 20.99 458.70 1047429 876946
61801932001 Diversion point 117.01 454.38 1051201 877465
61801932301 Other secondary 117.01 454.38 1051199 877463
61801932501 Return flow 117.02 454.44 1051231 877493
61801934001 Diversion point 2.96 450.78 1054391 876938
61801934302 Other secondary 31.45 450.31 1054869 878351
61801935001 Diversion point 128.44 449.49 1055954 876810
61801935005 Diversion point 2.84 449.88 1056177 876203
61801936001 Diversion point 128.65 449.03 1056360 877150
61801936002 Diversion point 128.51 449.32 1056171 876971
61801936003 Diversion point 2.99 449.67 1056353 876623
61801936004 Diversion point 2.94 449.83 1056264 876427
61801936006 Diversion point 2.36 450.21 1056158 875801
61801936007 Diversion point 2.33 450.37 1056066 875638
61801937301 Other secondary 31.62 449.87 1055283 878045
61801937303 Other secondary 31.43 450.36 1054716 878347
61801938001 Diversion point 32.14 448.92 1056354 877364
61801938002 Diversion point 128.66 449.03 1056424 877205
61801939001 Diversion point 1.55 449.26 1056459 878003
61801939301 Other secondary 1.55 449.26 1056459 878004
147
61801940001 Diversion point 1.67 449.05 1056689 877674
61801940002 Diversion point 162.59 448.63 1056749 877332
61801940301 Return flow 1.67 449.05 1056691 877682
61801941301 Other secondary 38.56 428.44 1079127 866450
61801943001 Diversion point 169.94 445.61 1060392 877677
61801945001 Diversion point 173.33 443.12 1061961 879061
61801946001 Diversion point 173.37 443.12 1061978 879105
61801947001 Diversion point 173.39 443.06 1061997 879130
61801948001 Diversion point 0.50 443.24 1061604 879624
61801948002 Diversion point 0.32 443.40 1061447 879528
61801948301 Other secondary 0.50 443.24 1061605 879624
61801948302 Other secondary 0.32 443.40 1061443 879524
61801949001 Diversion point 8.73 445.84 1061307 881755
61801949002 Diversion point 8.64 446.05 1061075 881709
61801950001 Diversion point 10.58 444.83 1061391 880650
61801950002 Diversion point 10.71 444.70 1061691 880451
61801950301 Other secondary 10.58 444.83 1061388 880651
61801950302 Other secondary 10.71 444.70 1061690 880451
61801952301 Other secondary 1.63 318.84 1159954 862513
61801952302 Other secondary 1.56 318.97 1159866 862718
61801952303 Other secondary 1.47 319.02 1159864 862814
61801952304 Other secondary 1.47 319.08 1159869 862922
61801953001 Diversion point 188.13 441.87 1063118 879531
61801954001 Diversion point 1.87 313.96 1162198 853539
61801954002 Diversion point 0.25 316.83 1161152 854870
61801954301 Other secondary 1.87 313.96 1162198 853539
61801954302 Other secondary 0.25 316.83 1161153 854871
61801955101 Other secondary 1.41 315.17 1162391 856293
61801955201 Other secondary 1.00 315.38 1162448 855950
61801955301 Other secondary 1.00 315.38 1162449 855957
61801956001 Diversion point 66.71 449.95 1059022 870662
61801956301 Other secondary 66.71 449.95 1059021 870665
61801957301 Other secondary 73.09 449.35 1059585 870685
61801958001 Diversion point 9.24 449.68 1060962 869895
61801958301 Other secondary 9.24 449.68 1060956 869886
61801961001 Diversion point 90.16 445.52 1061749 874004
61801963001 Diversion point 97.22 441.12 1064005 878110
61801963301 Other secondary 97.22 441.12 1064005 878112
61801963302 Other secondary 97.28 440.85 1064236 878347
61801964001 Diversion point 1.24 445.87 1064385 872455
148
61801964002 Diversion point 1.32 445.77 1064376 872626
61801964003 Diversion point 0.99 446.11 1065579 872663
61801964301 Other secondary 1.24 445.87 1064384 872460
61801964302 Other secondary 0.99 446.11 1065577 872672
61801967001 Diversion point 293.84 439.32 1066077 877944
61801967301 Other secondary 0.12 439.92 1066007 877288
61801968001 Diversion point 295.93 438.84 1066669 878142
61801968002 Diversion point 299.06 438.12 1067597 878333
61801968003 Diversion point 5.22 439.04 1067850 876341
61801968004 Diversion point 5.21 439.10 1067772 876305
61801968005 Diversion point 4.70 439.98 1067511 875296
61801968006 Diversion point 3.88 440.14 1067636 875199
61801969002 Diversion point 6.44 438.21 1068086 877439
61801969301 Other secondary 6.44 438.21 1068085 877435
61801969501 Return flow 299.25 437.75 1068097 878156
61801970001 Diversion point 306.97 436.90 1069061 878298
61801970002 Diversion point 307.67 436.58 1069396 878527
61801971301 Other secondary 310.67 435.01 1071616 878410
61801972001 Diversion point 1.69 448.02 1061050 889760
61801973001 Diversion point 3.31 447.18 1061598 887909
61801973301 Other secondary 3.31 447.18 1061593 887907
61801974001 Diversion point 3.40 446.91 1061746 888191
61801974301 Other secondary 3.40 446.91 1061750 888192
61801974302 Other secondary 3.40 446.96 1061818 888232
61801974303 Other secondary 3.41 446.78 1062033 888235
61801974304 Other secondary 66.20 446.52 1062166 888027
61801975001 Diversion point 0.21 446.80 1062969 889072
61801975002 Diversion point 8.42 446.36 1062953 888546
61801975301 Other secondary 0.21 446.80 1062966 889070
61801975401 Other secondary 0.00 446.13 1062773 887866
61801975501 Return flow 8.66 445.86 1063049 887826
61801976001 Diversion point 8.42 446.36 1062952 888547
61801976301 Other secondary 8.42 446.36 1062953 888544
61801977001 Diversion point 75.21 445.62 1063284 887634
61801977002 Diversion point 75.28 445.47 1063508 887509
61801977301 Other secondary 75.21 445.62 1063294 887632
61801978001 Diversion point 76.24 444.99 1063671 886838
61801979001 Diversion point 2.92 445.48 1063122 886385
61801980001 Diversion point 81.01 443.66 1065288 886222
61801981001 Diversion point 81.14 443.40 1065499 885822
149
61801981002 Diversion point 81.15 443.35 1065499 885736
61801981003 Diversion point 81.20 443.25 1065532 885627
61801981004 Diversion point 92.47 442.90 1065557 885203
61801981005 Diversion point 94.70 442.72 1065734 884958
61801982001 Diversion point 95.37 442.07 1066301 884380
61801982301 Other secondary 95.37 442.07 1066302 884378
61801983001 Diversion point 98.68 441.50 1066965 883976
61801983002 Diversion point 98.90 441.39 1067169 883940
61801984001 Diversion point 99.09 441.01 1067365 883506
61801985001 Diversion point 99.09 441.01 1067370 883512
61801987001 Diversion point 99.12 440.80 1067307 883378
61801988001 Diversion point 8.21 442.79 1068751 886922
61801988002 Diversion point 8.82 442.06 1068554 886017
61801988003 Diversion point 9.05 441.80 1068882 885656
61801990001 Diversion point 113.36 438.83 1068330 882005
61801991001 Diversion point 4.52 438.72 1072498 883357
61801991301 Other secondary 4.52 438.72 1072498 883353
61801992001 Diversion point 124.59 436.05 1071398 880435
61801993001 Diversion point 124.64 436.16 1071385 880318
61801993301 Other secondary 124.61 436.05 1071383 880397
61801994001 Diversion point 448.23 433.25 1074116 878208
61801995001 Diversion point 19.06 431.11 1077072 878529
61801995002 Diversion point 18.85 431.27 1077202 878619
61801995301 Other secondary 19.06 431.16 1077071 878534
61801995302 Other secondary 18.85 431.18 1077205 878618
61801996001 Diversion point 512.13 426.83 1082633 875702
61801996002 Diversion point 512.13 426.83 1082634 875702
61801996003 Diversion point 512.13 426.83 1082634 875702
61801996004 Diversion point 486.53 428.40 1080591 876406
61801996301 Other secondary 512.13 426.83 1082636 875700
61801997001 Diversion point 485.15 429.00 1080048 877063
61801997501 Return flow 486.26 428.66 1080198 876773
61801998001 Diversion point 11.11 431.96 1081463 881866
61801998002 Diversion point 11.11 431.96 1081465 881872
61801998003 Diversion point 11.11 431.96 1081465 881872
61801998004 Diversion point 11.16 431.90 1081434 881778
61801998005 Diversion point 11.18 431.85 1081411 881706
61801998301 Other secondary 11.11 431.96 1081464 881868
61801999301 Other secondary 0.42 428.33 1081084 875489
61802000001 Diversion point 525.62 424.67 1084147 873110
150
61802000002 Diversion point 9.70 425.29 1083339 872791
61802000301 Other secondary 9.70 425.29 1083335 872792
61802001001 Diversion point 537.54 423.24 1085428 871423
61802002001 Diversion point 552.13 422.55 1085980 870561
61802003001 Diversion point 551.24 422.91 1085620 871031
61802004301 Other secondary 552.23 422.44 1086002 870379
61802005001 Diversion point 562.27 419.78 1087410 867385
61802005002 Diversion point 562.69 419.54 1087487 867093
61802006001 Diversion point 564.34 418.83 1088312 866136
61802006002 Diversion point 564.37 418.70 1088472 865993
61802006003 Diversion point 562.85 419.28 1087667 866706
61802006004 Diversion point 552.98 421.49 1085902 869003
61802006301 Other secondary 564.34 418.83 1088313 866135
61802006401 Other secondary 0.00 418.85 1088212 866260
61802007001 Diversion point 1.06 434.74 1073483 870088
61802007002 Diversion point 1.90 434.38 1074004 869715
61802007003 Diversion point 2.01 433.86 1074084 869152
61802007301 Other secondary 1.06 434.74 1073484 870087
61802008001 Diversion point 15.46 432.97 1075124 868591
61802008301 Other secondary 15.46 432.97 1075123 868594
61802009001 Diversion point 7.05 434.73 1072945 866185
61802009301 Other secondary 7.05 434.73 1072943 866183
61802010001 Diversion point 7.18 434.40 1073178 866449
61802010301 Other secondary 7.19 434.40 1073188 866476
61802011001 Diversion point 32.80 430.40 1076497 866250
61802011002 Diversion point 32.86 430.13 1076792 866418
61802011003 Diversion point 32.95 429.96 1076959 866519
61802011004 Diversion point 2.85 429.84 1077378 866198
61802011301 Other secondary 2.85 429.84 1077381 866202
61802012001 Diversion point 38.91 428.15 1079449 866419
61802012301 Other secondary 38.91 428.15 1079450 866418
61802013001 Diversion point 0.35 427.50 1079718 868509
61802014001 Diversion point 70.47 418.39 1088687 865537
61802014002 Diversion point 70.28 418.68 1088257 865496
61802015001 Diversion point 640.04 417.40 1089728 864894
61802016001 Diversion point 643.16 415.67 1091926 864876
61802017301 Other secondary 643.83 415.56 1092609 864859
61802018001 Diversion point 6.51 414.74 1093012 865060
61802020001 Diversion point 650.86 413.90 1093939 864566
61802021001 Diversion point 651.01 413.69 1094113 864237
151
61802021401 Other secondary 0.00 414.62 1093178 863525
61802022001 Diversion point 650.83 413.95 1093924 864601
61802022401 Other secondary 0.00 415.20 1094073 866064
61802022402 Other secondary 0.00 415.11 1093813 865871
61802023001 Diversion point 651.07 413.51 1094433 864227
61802024001 Diversion point 651.07 413.40 1094488 864237
61802024002 Diversion point 651.20 413.29 1094649 864265
61802025001 Diversion point 651.21 413.29 1094692 864273
61802026001 Diversion point 652.81 413.08 1095095 864401
61802026002 Diversion point 652.88 412.84 1095337 864275
61802027001 Diversion point 1.63 429.43 1079631 856785
61802028002 Diversion point 1.66 429.17 1079836 856597
61802028301 Other secondary 3.05 431.16 1077089 858031
61802029001 Diversion point 2.43 424.44 1084022 857920
61802029002 Diversion point 25.14 422.60 1085923 858731
61802029301 Other secondary 2.43 424.44 1084019 857916
61802030001 Diversion point 31.14 421.12 1087603 859588
61802030002 Diversion point 3.09 421.01 1088001 859523
61802030301 Other secondary 3.09 421.01 1088002 859521
61802031001 Diversion point 740.40 408.80 1100000 863877
61802031101 Other secondary 740.40 408.80 1099999 863877
61802031201 Other secondary 741.71 408.64 1100196 863869
61802032001 Diversion point 742.23 408.32 1100879 863890
61802033001 Diversion point 753.62 406.47 1102570 864941
61802034001 Diversion point 760.56 405.11 1103789 865009
61802034002 Diversion point 760.64 405.04 1103963 864917
61802035001 Diversion point 761.56 403.83 1104543 865988
61802036001 Diversion point 764.50 403.43 1105277 865875
61802036002 Diversion point 0.05 405.58 1106131 863662
61802036301 Other secondary 0.05 405.58 1106130 863662
61802037001 Diversion point 9.10 414.30 1096616 877635
61802037002 Diversion point 9.67 414.10 1096730 877153
61802038001 Diversion point 27.52 411.47 1098222 874074
61802039001 Diversion point 28.51 410.09 1098764 872549
61802040001 Diversion point 38.38 409.39 1099432 871973
61802041001 Diversion point 55.89 405.75 1102645 869079
61802041101 Other secondary 71.49 404.24 1103857 867888
61802041201 Other secondary 71.12 404.40 1103943 868103
61802042001 Diversion point 56.02 405.35 1103264 869045
61802042002 Diversion point 70.98 404.92 1103594 868647
152
61802043001 Diversion point 71.00 404.92 1103630 868607
61802044001 Diversion point 841.54 401.02 1107266 867507
61802044301 Other secondary 841.54 401.02 1107264 867509
61802045001 Diversion point 841.75 400.63 1107499 867156
61802046001 Diversion point 852.46 398.84 1109025 866941
61802047001 Diversion point 865.60 395.70 1111390 868593
61802048001 Diversion point 43.65 396.04 1111429 869812
61802048002 Diversion point 44.65 395.38 1111559 868974
61802048301 Other secondary 43.65 396.04 1111427 869805
61802049001 Diversion point 910.60 394.98 1111929 869321
61802050001 Diversion point 911.38 394.08 1112619 868505
61802051101 Other secondary 40.18 387.81 1117378 863437
61802051201 Other secondary 41.39 386.34 1118033 864694
61802051301 Other secondary 40.69 386.93 1117525 864394
61802052001 Diversion point 975.59 382.68 1120833 865958
61802052002 Diversion point 977.65 382.17 1121426 865972
61802053001 Diversion point 977.83 381.96 1121853 866046
61802054001 Diversion point 982.82 381.01 1122963 865549
61802056001 Diversion point 3.48 387.29 1126310 875785
61802056301 Other secondary 3.48 387.29 1126309 875799
61802057001 Diversion point 2.48 385.88 1125027 873971
61802057301 Other secondary 2.48 385.88 1125031 873967
61802058001 Diversion point 1052.55 376.37 1126969 866710
61802058002 Diversion point 1052.58 376.09 1127223 866562
61802059001 Diversion point 1060.32 375.88 1127489 866544
61802060001 Diversion point 1052.51 376.45 1126852 866832
61802060002 Diversion point 1061.09 375.44 1128044 866256
61802060003 Diversion point 1061.31 374.51 1127138 865889
61802061001 Diversion point 1067.00 371.72 1127924 863537
61802062001 Diversion point 5.34 375.85 1121579 860024
61802062301 Other secondary 5.34 375.85 1121577 860023
61802063001 Diversion point 1088.05 367.95 1127701 859904
61802064001 Diversion point 6.12 372.32 1123679 856632
61802064002 Diversion point 6.14 372.22 1123763 856741
61802064003 Diversion point 8.97 371.60 1124221 857326
61802064004 Diversion point 9.00 371.66 1124256 857402
61802064301 Other secondary 8.97 371.60 1124222 857330
61802065001 Diversion point 14.30 368.07 1127822 859082
61802065002 Diversion point 13.50 368.30 1127551 858869
61802066001 Diversion point 14.30 367.94 1127868 859081
153
61802067001 Diversion point 1106.43 365.25 1130078 860047
61802067002 Diversion point 1106.50 365.09 1130273 860045
61802067003 Diversion point 1106.60 364.87 1130638 860057
61802067401 Other secondary 0.00 365.30 1130327 860195
61802069001 Diversion point 18.73 342.17 1146243 861705
61802069301 Other secondary 18.97 341.80 1146112 861167
61802070001 Diversion point 67.77 340.39 1146046 859519
61802070002 Diversion point 68.10 340.00 1146219 859082
61802070003 Diversion point 69.03 339.44 1146738 858854
61802070004 Diversion point 1267.19 339.02 1147261 858701
61802070005 Diversion point 1267.43 338.91 1147434 858695
61802071001 Diversion point 1267.58 338.53 1147791 858951
61802072001 Diversion point 1336.15 318.61 1160719 861761
61802072002 Diversion point 1351.65 318.18 1160448 862161
61802072003 Diversion point 1358.44 317.37 1161392 862564
61802073301 Other secondary 0.77 325.75 1154182 865512
61802073302 Other secondary 0.88 325.64 1154008 865472
61802074001 Diversion point 1432.27 302.12 1174030 857362
61802074301 Other secondary 1432.27 302.12 1174029 857361
61802437301 Other secondary 117.38 453.70 1052231 877187
61802438001 Diversion point 124.55 451.45 1053485 877687
61802438301 Other secondary 124.33 451.88 1053331 877288
61802439001 Diversion point 167.21 447.67 1058010 877341
61802439002 Diversion point 167.21 447.67 1058012 877340
61802439301 Other secondary 167.21 447.67 1058014 877339
61802440001 Diversion point 168.53 446.15 1059512 878157
61802441001 Diversion point 172.19 444.32 1061321 877662
61802441002 Diversion point 172.66 444.11 1061329 877933
61802441003 Diversion point 172.90 443.79 1061703 878184
61802442001 Diversion point 12.68 443.77 1062445 880996
61802442002 Diversion point 12.61 444.06 1062196 880944
61802442301 Other secondary 12.68 443.77 1062449 880994
61802442302 Other secondary 12.61 444.06 1062195 880936
61802443001 Diversion point 13.20 442.71 1062236 879774
61802443301 Other secondary 187.33 442.45 1062363 879585
61802444001 Diversion point 49.01 455.41 1053636 868335
61802444301 Diversion point 49.01 455.41 1053634 868336
61802444302 Other secondary 40.99 456.97 1053640 867044
61802445001 Diversion point 75.28 447.77 1060560 871732
61802445002 Diversion point 11.29 447.83 1060542 871635
154
61802445003 Diversion point 10.42 447.94 1060454 871545
61802445004 Diversion point 86.63 447.48 1060886 871732
61802445301 Other secondary 86.63 447.48 1060901 871734
61802446001 Diversion point 88.02 446.24 1061350 873198
61802446002 Diversion point 88.07 446.19 1061346 873264
61802447001 Diversion point 97.06 441.39 1063854 877885
61802447002 Diversion point 97.06 441.39 1063853 877883
61802447003 Diversion point 97.06 441.39 1063851 877881
61802447301 Other secondary 97.06 441.39 1063849 877879
61802448001 Diversion point 4.44 442.94 1064191 875121
61802449001 Diversion point 451.49 431.59 1076505 878281
61802450001 Diversion point 650.78 414.16 1093813 864794
61803815001 Diversion point 1438.53 298.60 1176891 856620
61803816001 Diversion point 1448.78 297.33 1177717 856591
61803816301 Other secondary 2.12 297.41 1177839 856512
61803816302 Other secondary 2.11 297.41 1177916 856483
61803816303 Other secondary 2.10 297.49 1178002 856582
61803816304 Other secondary 2.12 297.41 1177837 856513
61803816501 Return flow 1450.91 297.33 1177706 856566
61803817001 Diversion point 1454.72 296.95 1177443 856091
61803818301 Other secondary 1496.42 284.51 1179361 845822
61803819001 Diversion point 1516.90 280.63 1182918 842832
61803820001 Diversion point 1519.89 277.68 1182820 839576
61803821001 Diversion point 1519.92 277.61 1182735 839517
61803822001 Diversion point 1520.17 277.21 1182332 839239
61803823001 Diversion point 16.00 280.46 1180885 840922
61803824001 Diversion point 17.74 278.94 1180426 839319
61803824002 Diversion point 17.74 278.94 1180426 839318
61803824003 Diversion point 1518.25 278.69 1182143 840588
61803824004 Diversion point 17.74 278.94 1180425 839321
61803824005 Diversion point 17.03 279.52 1180185 839941
61803824301 Other secondary 17.74 278.94 1180427 839316
61803824501 Return flow 17.81 278.75 1180570 839281
61803825301 Other secondary 0.37 291.86 1170854 829769
61803825302 Other secondary 0.09 290.31 1171885 830666
61803826001 Diversion point 17.24 278.63 1181258 839839
61803826401 Other secondary 0.00 278.79 1181088 839779
61803827301 Other secondary 129.49 278.14 1181332 839425
61803828001 Diversion point 129.83 277.43 1181745 838771
61803828002 Diversion point 129.79 277.51 1181658 838909
155
61803828003 Diversion point 129.63 277.66 1181732 839047
61803828301 Other secondary 129.63 277.66 1181730 839045
61803829001 Diversion point 1658.12 274.04 1184501 837094
61803829002 Diversion point 1650.78 276.41 1182889 838364
61803829301 Other secondary 1650.78 276.41 1182888 838366
61803830001 Diversion point 1658.12 274.04 1184501 837095
61803830002 Diversion point 1650.78 276.41 1182889 838364
61803830301 Other secondary 1650.78 276.41 1182889 838364
61803831001 Diversion point 1665.28 268.21 1186894 833583
61803832001 Diversion point 1665.28 268.21 1186894 833583
61803833001 Diversion point 1665.28 268.21 1186894 833583
61803834001 Diversion point 1665.28 268.21 1186894 833583
61803834002 Diversion point 1665.28 268.21 1186894 833583
61803835001 Diversion point 14.72 258.92 1189816 825593
61803836001 Diversion point 1711.27 258.76 1189890 825316
61803836501 Return flow 1711.27 258.76 1189887 825280
61803837001 Diversion point 1717.50 258.09 1190519 824528
61803837002 Diversion point 1717.45 258.22 1190376 824625
61803837003 Diversion point 1711.39 258.42 1190165 824824
61803838001 Diversion point 0.95 255.71 1192190 821797
61803838002 Diversion point 0.94 255.76 1192178 821771
61803838301 Other secondary 0.11 256.08 1191931 821429
61803839001 Diversion point 1737.23 254.46 1193565 821994
61803839002 Diversion point 1737.23 254.46 1193564 821994
61803839003 Diversion point 1737.23 254.46 1193565 821994
61803839301 Other secondary 1737.23 254.46 1193564 821994
61803840001 Diversion point 28.63 257.28 1195690 835732
61803840002 Diversion point 28.45 257.82 1195200 835554
61803841001 Diversion point 60.61 248.30 1199614 826848
61803841002 Diversion point 59.68 248.53 1199246 826952
61803841401 Other secondary 0.00 248.93 1198862 826816
61803842001 Diversion point 69.27 244.02 1201784 821480
61803843001 Diversion point 1883.32 239.35 1206251 821050
61803844001 Diversion point 1968.60 224.48 1216273 820339
61803845301 Other secondary 2068.26 198.06 1233603 816934
61803846001 Diversion point 3468.60 173.30 1246322 817345
61803846002 Diversion point 3468.60 173.30 1246322 817344
61803846301 Other secondary 3468.60 173.30 1246322 817343
61803846501 Return flow 3468.60 173.30 1246322 817345
61803847001 Diversion point 3474.94 167.56 1249645 815849
156
61803847002 Diversion point 3474.38 168.55 1249070 817173
61803848001 Diversion point 3492.03 162.58 1251657 813181
61803848002 Diversion point 3510.49 159.22 1252989 812327
61803848301 Other secondary 3492.03 162.52 1251782 813079
61803848302 Other secondary 3510.49 159.40 1253350 812264
61803849301 Other secondary 0.90 192.74 1261185 858989
61803850001 Diversion point 4074.25 131.21 1259936 793848
61803850002 Diversion point 4074.58 130.72 1259344 794004
61803850003 Diversion point 4106.60 128.27 1259055 793601
61803851001 Diversion point 4135.99 119.03 1260267 786461
61803852001 Diversion point 4207.08 110.11 1260766 779259
61803853501 Return flow 4213.19 107.11 1261231 776948
61803854001 Diversion point 4928.17 103.19 1259568 772338
61803855001 Diversion point 4928.21 103.00 1259556 772014
61803856001 Diversion point 4928.30 102.47 1259347 771333
61803856002 Diversion point 4928.27 102.79 1259559 771672
61803858001 Diversion point 5092.99 70.31 1277900 753843
61803858002 Diversion point 5089.59 71.05 1277091 754673
61803858003 Diversion point 5086.43 71.44 1276795 755179
61803858004 Diversion point 5085.17 71.92 1276703 755850
61803858005 Diversion point 5083.93 72.66 1276797 756987
61803859001 Diversion point 5093.70 68.16 1278889 751099
61803859401 Other secondary 0.00 68.16 1279083 751108
61803860001 Diversion point 5781.05 34.46 1294094 728232
61803860401 Other secondary 0.00 34.08 1294369 727926
61803860501 Return flow 30.14 33.60 1295134 728316
61803861001 Diversion point 5812.64 31.59 1296124 725896
61803861401 Other secondary 0.00 32.78 1297862 726921
61803862001 Diversion point 5812.76 31.07 1296557 725073
61803863001 Diversion point 5874.47 21.91 1302216 715500
61803863002 Diversion point 5870.77 25.66 1298861 718896
61803865001 Diversion point 48.32 249.71 1199160 860050
61803865002 Diversion point 48.32 249.71 1199162 860057
61803865003 Diversion point 48.32 249.71 1199160 860049
61803865004 Diversion point 48.32 249.71 1199161 860053
61803865301 Other secondary 48.32 249.71 1199160 860049
61803865501 Return flow 48.32 249.71 1199160 860045
61803865502 Return flow 48.32 249.71 1199159 860041
61803866001 Diversion point 48.97 249.49 1199131 859769
61803866002 Diversion point 49.49 249.42 1199042 859680
157
61803866401 Other secondary 0.00 249.66 1198963 859892
61803866501 Return flow 86.86 248.84 1199312 858903
61803867301 Other secondary 87.14 248.90 1199319 858780
61803868001 Diversion point 87.73 248.28 1199570 857776
61803868301 Other secondary 87.23 248.41 1199467 858304
61803869001 Diversion point 92.46 247.89 1199734 857681
61803869401 Other secondary 0.00 248.04 1199348 857038
61803870001 Diversion point 14.69 337.99 1132517 882823
61803870301 Other secondary 14.69 337.99 1132519 882820
61803871001 Diversion point 3.97 331.17 1139267 883090
61803871002 Diversion point 4.06 330.85 1139440 882657
61803871301 Other secondary 3.97 331.17 1139269 883089
61803871302 Other secondary 4.06 330.85 1139443 882654
61803872001 Diversion point 51.50 328.67 1141285 882785
61803872002 Diversion point 52.02 328.13 1142035 882383
61803872003 Diversion point 50.38 329.29 1140824 882485
61803872301 Other secondary 50.38 329.29 1140823 882488
61803872302 Other secondary 52.02 328.13 1142037 882385
61803873001 Diversion point 51.50 328.67 1141280 882791
61803873002 Diversion point 52.02 328.13 1142041 882388
61803873301 Other secondary 52.02 328.13 1142033 882381
61803874001 Diversion point 11.39 329.65 1141794 880066
61803874002 Diversion point 11.56 329.32 1142067 880342
61803875001 Diversion point 2.86 329.15 1143593 886408
61803875002 Diversion point 2.52 329.59 1143385 887023
61803875301 Other secondary 2.52 329.59 1143386 887019
61803876301 Other secondary 94.10 323.30 1147965 882587
61803877001 Diversion point 103.83 320.83 1150973 881797
61803877301 Other secondary 103.61 321.37 1150534 882256
61803877302 Other secondary 103.83 320.83 1150976 881794
61803878301 Other secondary 108.18 320.44 1151548 881564
61803878302 Other secondary 109.42 319.85 1151999 882014
61803879301 Other secondary 110.56 318.95 1152855 882115
61803880301 Other secondary 295.37 285.39 1176374 866933
61803881001 Diversion point 295.96 284.63 1177101 867162
61803882001 Diversion point 0.48 285.48 1176562 871736
61803882002 Diversion point 0.79 285.11 1176579 871245
61803882003 Diversion point 0.94 285.09 1176669 871076
61803882004 Diversion point 1.50 284.27 1177497 870151
61803882005 Diversion point 1.51 284.27 1177479 870071
158
61803882301 Other secondary 0.48 285.48 1176561 871732
61803882302 Other secondary 0.79 285.11 1176579 871247
61803882303 Other secondary 0.94 285.09 1176666 871079
61803882304 Other secondary 1.50 284.27 1177496 870155
61803883301 Other secondary 7.27 287.61 1176380 878234
61803883302 Other secondary 1.94 285.25 1178233 876689
61803883303 Other secondary 1.83 281.57 1181324 874431
61803883304 Other secondary 31.22 281.55 1181241 874206
61803883305 Other secondary 33.15 281.31 1181461 874172
61803884001 Diversion point 366.67 273.32 1188420 870385
61803884401 Other secondary 0.00 273.10 1188558 870978
61803884402 Other secondary 0.00 273.76 1188359 870969
61803886001 Diversion point 434.62 249.18 1202403 859977
61803886401 Other secondary 0.00 245.67 1202785 859495
61803886402 Other secondary 0.00 245.72 1202727 859573
61803887001 Diversion point 531.47 245.57 1201977 856277
61803887002 Diversion point 541.79 239.63 1207755 854664
61803887003 Diversion point 531.55 245.33 1202353 856186
61803887301 Other secondary 531.47 245.57 1201982 856276
61803888001 Diversion point 531.85 244.80 1202923 856468
61803888002 Diversion point 531.94 244.50 1203365 856380
61803888003 Diversion point 531.96 244.40 1203528 856373
61803888004 Diversion point 532.03 244.07 1203669 856754
61803888005 Diversion point 532.53 243.70 1203997 857055
61803889001 Diversion point 532.53 243.70 1203974 857051
61803889002 Diversion point 532.51 243.75 1203847 857042
61803890001 Diversion point 582.60 231.82 1211133 848489
61803891001 Diversion point 598.53 225.55 1214248 845065
61803891002 Diversion point 598.30 225.97 1214287 845545
61803892301 Other secondary 8.27 242.66 1194690 847360
61803893301 Other secondary 4.86 237.35 1201019 839972
61803894301 Other secondary 9.92 240.90 1200224 852309
61803895001 Diversion point 784.15 216.42 1219753 837734
61803896001 Diversion point 838.35 208.28 1226719 835849
61803896501 Return flow 8.71 205.12 1229197 837908
61803896502 Return flow 838.91 207.81 1227176 835325
61803897301 Other secondary 838.81 208.07 1227016 835698
61803898001 Diversion point 838.91 207.81 1227195 835320
61803899001 Diversion point 841.20 206.40 1227798 834467
61803899002 Diversion point 843.17 206.03 1228133 834267
159
61803899003 Diversion point 844.25 205.76 1228495 834518
61803900001 Diversion point 861.63 201.19 1231303 832383
61803900002 Diversion point 861.76 200.81 1231370 832853
61803900003 Diversion point 861.86 200.49 1231636 833086
61803900004 Diversion point 861.96 199.92 1231983 832516
61803900005 Diversion point 862.01 199.76 1232135 832261
61803900006 Diversion point 388.00 200.46 1232402 833380
61803900007 Diversion point 388.00 200.46 1232401 833374
61803900008 Diversion point 388.17 200.14 1232238 832912
61803900301 Other secondary 1.50 207.11 1227330 833492
61803901001 Diversion point 0.34 242.54 1209700 867194
61803901301 Other secondary 0.34 242.54 1209698 867191
61803902001 Diversion point 6.47 244.98 1208048 872706
61803902301 Other secondary 6.47 244.98 1208049 872705
61803903301 Other secondary 3.88 243.96 1214194 877734
61803904001 Diversion point 26.99 232.52 1219613 867646
61803904401 Other secondary 0.01 232.76 1219359 867623
61803904402 Other secondary 0.04 233.33 1219135 868102
61803905301 Other secondary 7.14 227.43 1216317 857669
61803906001 Diversion point 32.72 222.51 1222099 856416
61803906301 Other secondary 32.72 222.51 1222099 856416
61803906302 Other secondary 32.76 222.40 1222149 856274
61803906303 Other secondary 33.18 221.94 1222565 855828
61803907301 Other secondary 1257.85 196.26 1233303 828521
61803908001 Diversion point 1271.38 193.21 1234785 827068
61803908002 Diversion point 1270.55 194.40 1234450 827443
61803908003 Diversion point 1270.40 194.48 1234089 827581
61805172001 Diversion point 2047.64 203.25 1229944 816882
61805172002 Diversion point 2098.86 183.32 1242859 814086
61805172301 Other secondary 2047.64 203.25 1229945 816881
61805172302 Other secondary 2098.86 183.32 1242860 814087
61805173001 Diversion point 10122.36 15.74 1304818 708758
61805173002 Diversion point 64.04 9.69 1315130 707640
61805173003 Diversion point 5.04 9.86 1313093 708260
61805173501 Return flow 0.54 15.66 1305262 710000
61805173502 Return flow 3.64 11.58 1311042 709623
61805174001 Diversion point 10122.36 15.74 1304814 708759
61805174002 Diversion point 64.04 9.69 1315129 707639
61805174003 Diversion point 5.04 9.86 1313093 708260
61805174501 Return flow 0.54 15.66 1305261 710000
160
61805174502 Return flow 3.64 11.58 1311040 709621
61805175001 Diversion point 10122.36 15.74 1304822 708756
61805175002 Diversion point 64.04 9.69 1315129 707638
61805175003 Diversion point 5.04 9.86 1313092 708260
61805175501 Return flow 0.54 15.66 1305261 710001
61805175502 Return flow 3.64 11.58 1311040 709621
61805176001 Diversion point 10122.36 15.74 1304823 708756
61805176002 Diversion point 64.04 9.69 1315127 707637
61805176003 Diversion point 5.04 9.86 1313092 708260
61805176501 Return flow 0.54 15.66 1305261 710002
61805176502 Return flow 3.64 11.58 1311040 709621
61805177001 Diversion point 10122.36 15.74 1304814 708759
61805177002 Diversion point 64.04 9.69 1315127 707636
61805177003 Diversion point 5.04 9.86 1313092 708260
61805177501 Return flow 0.54 15.66 1305262 709999
61805177502 Return flow 3.64 11.58 1311039 709620
61805178001 Diversion point 10122.36 15.74 1304822 708756
61805178002 Diversion point 64.04 9.69 1315128 707638
61805178003 Diversion point 5.04 9.86 1313091 708261
61805178501 Return flow 0.54 15.66 1305261 710002
61805178502 Return flow 3.64 11.58 1311039 709621
61805484301 Other secondary 6189.11 15.74 1304803 708764
61805485001 Diversion point 5197.50 49.69 1291430 739741
61805486001 Diversion point 5093.70 68.16 1278891 751096
61805486002 Diversion point 493.42 51.11 1276510 732315
61805486301 Other secondary 493.42 51.11 1276510 732315
61805488001 Diversion point 1665.28 268.21 1186894 833583
61805488002 Diversion point 1695.67 260.10 1189474 826999
61805488003 Diversion point 1737.23 254.46 1193564 821994
61805488004 Diversion point 1759.10 246.30 1199350 820056
61805488301 Other secondary 1665.28 268.21 1186895 833583
61805488302 Other secondary 1695.67 260.10 1189474 826999
61805488303 Other secondary 1737.23 254.46 1193564 821994
61805488304 Other secondary 1759.10 246.30 1199351 820056
61805488501 Return flow 1737.23 254.46 1193569 821992
61805488502 Return flow 1695.67 260.10 1189474 826999
61805488503 Return flow 1737.23 254.46 1193565 821992
61805488504 Return flow 1759.47 245.22 1200122 820920
61805488505 Return flow 1670.74 266.14 1188873 832031
161
APPENDIX C: SAN ANTONIO BASIN RESULTS
162
C.1 INTRODUCTION
The following appendix contains a table of watershed parameters for all of
the control points in the San Antonio River basin. The table includes the control
point identification number, type of control point, drainage area in square miles,
flowlength to outlet in miles, and the x and y coordinates of the control point
location based on the TSMS Albers projection described in Chapter 3.
163
ID Type Area (mi
2
) Flowlength (mi) X-coord. Y-coord.
17 Other primary 8.19 239.88 1141205 820193
18 Stream gage 44.11 225.83 1145844 805859
19 Stream gage 136.04 240.27 1151867 817732
20 Stream gage 187.04 220.40 1153861 800111
21 Stream gage 633.63 291.08 1103175 819853
22 Other primary 15.60 286.46 1106384 816556
23 Stream gage 648.84 286.46 1106384 816556
25 Other primary 58.27 287.55 1114293 816171
27 Stream gage 961.51 226.85 1137676 789273
28 Stream gage 1310.35 215.59 1148255 788584
29 Stream gage 1737.49 202.78 1159610 786703
30 Other primary 9.41 203.90 1159010 787572
31 Stream gage 64.55 200.06 1165646 789759
32 Stream gage 2107.81 151.70 1188440 755639
33 Stream gage 68.32 275.27 1125713 845983
34 Stream gage 273.97 219.28 1163329 826565
35 Stream gage 825.42 139.12 1201350 762803
36 Stream gage 239.26 118.14 1216886 752675
37 Stream gage 3906.02 63.15 1255367 723509
38 Stream gage 10122.30 6.97 1304639 708808
241 Other primary 4.45 284.36 1105203 813821
242 Other primary 7.20 282.34 1107363 813859
261 Other primary 59.76 252.11 1132584 818585
262 Other primary 28.06 256.28 1126769 819655
263 Other primary 11.78 259.24 1119812 820932
901 Confluence 107.65 354.96 1065586 855027
902 Confluence 50.53 278.56 1122389 847713
903 Confluence 24.11 260.03 1126488 824108
904 Confluence 56.08 255.02 1132761 822256
905 Confluence 475.40 186.56 1180626 809544
906 Confluence 755.52 149.25 1196262 773121
907 Confluence 3143.40 128.97 1207018 756104
908 Confluence 3570.33 110.25 1219272 744714
909 Confluence 831.92 249.02 1121266 797350
910 Confluence 1045.68 224.89 1139667 788060
911 Confluence 1298.66 218.04 1146116 789699
912 Confluence 1310.03 216.14 1147923 788956
913 Confluence 357.45 213.49 1151844 791754
164
914 Confluence 1719.80 208.93 1154518 786466
915 Confluence 128.13 216.13 1151052 794740
916 Confluence 1846.69 193.52 1168399 785071
917 Confluence 1939.38 182.73 1175172 778027
918 Confluence 1954.60 179.92 1176827 775819
11903220001 Diversion point 55.01 290.40 1115350 819278
11903220301 Other secondary 55.01 290.40 1115348 819277
11903431001 Diversion point 833.44 134.55 1203121 760734
11903476001 Diversion point 1.54 262.79 1124119 826044
11903476002 Diversion point 1.54 262.79 1124120 826044
11903476301 Other secondary 1.55 262.79 1124121 826044
11903693301 Other secondary 0.83 330.13 1088056 849803
11903752001 Diversion point 12.74 286.59 1114485 852321
11903767001 Diversion point 2238.79 140.91 1196495 757016
11903803001 Diversion point 3182.58 116.05 1216894 748587
11903808001 Diversion point 2107.17 152.63 1187287 755826
11903808002 Diversion point 2107.26 152.46 1187503 755909
11903824301 Other secondary 328.17 323.15 1089888 839945
11903837001 Diversion point 1904.07 185.28 1174178 780771
11903851001 Diversion point 2156.99 143.36 1193928 758738
11903852001 Diversion point 2156.20 143.90 1193198 758537
11903853301 Other secondary 3.79 332.99 1082582 844003
11903861001 Diversion point 2067.48 160.53 1183883 763155
11903887001 Diversion point 1740.43 199.79 1162989 784114
11903888001 Diversion point 1333.46 211.65 1151773 785808
11903897001 Diversion point 3.33 182.86 1175092 778133
11903897101 Other secondary 1936.02 182.81 1175292 778099
11903897201 Other secondary 1904.79 183.34 1175132 778664
11903897401 Other secondary 0.00 183.29 1174675 778212
11903898001 Diversion point 32.45 231.69 1147737 812984
11903909301 Other secondary 2.06 331.72 1084438 844155
11903944301 Other secondary 0.69 320.95 1093521 842461
11903944302 Other secondary 0.81 320.87 1093383 842315
11903949301 Other secondary 12.27 322.66 1101633 846405
11903994101 Other secondary 2051.40 161.50 1183360 763596
11903994201 Other secondary 2047.43 163.58 1182351 765289
11904001301 Other secondary 8.44 284.06 1117403 846519
11904002101 Other secondary 807.32 144.00 1199865 767465
11904002201 Other secondary 773.51 144.15 1199772 767780
11904025301 Other secondary 860.69 243.94 1125467 798903
165
11904025302 Other secondary 831.92 249.02 1121276 797366
11904025501 Return flow 860.67 244.07 1125306 798961
11904025502 Return flow 831.92 249.02 1121274 797363
11904026301 Other secondary 12.26 320.62 1092562 837497
11904051301 Other secondary 0.65 243.69 1155757 821445
11904105001 Diversion point 2.79 206.73 1161571 820557
11904105002 Diversion point 2.79 206.73 1161572 820552
11904105301 Other secondary 2.79 206.73 1161571 820546
11904117001 Diversion point 3782.70 79.07 1241435 723581
11904121001 Diversion point 1886.36 188.93 1171428 783010
11904134101 Other secondary 964.72 225.10 1139392 788264
11904134201 Other secondary 963.94 225.62 1138977 788715
11904135101 Other secondary 1050.29 224.26 1140504 787692
11904135201 Other secondary 963.94 225.67 1138970 788715
11904136101 Other secondary 1051.89 221.76 1142912 788401
11904136201 Other secondary 1050.30 224.21 1140547 787689
11904137101 Other secondary 237.36 217.99 1146087 789746
11904137201 Other secondary 1051.89 221.76 1142911 788401
11904138101 Other secondary 1059.36 220.85 1143588 788924
11904138201 Other secondary 1051.40 222.76 1141967 788224
11904139101 Other secondary 227.87 222.59 1140694 791513
11904139201 Other secondary 226.75 224.24 1139180 791567
11904140101 Other secondary 680.95 279.20 1107957 810817
11904140102 Other secondary 664.42 280.27 1106894 811723
11904140201 Other secondary 680.89 279.44 1107842 811158
11904140202 Other secondary 663.93 281.24 1107971 812578
11904141001 Diversion point 214.83 225.41 1139220 792928
11904149001 Diversion point 762.79 271.51 1105756 805189
11904151001 Diversion point 790.06 258.37 1111572 796540
11904159001 Diversion point 753.09 273.45 1105763 806483
11904170101 Other secondary 682.11 277.65 1107602 809487
11904170201 Other secondary 682.12 277.54 1107550 809529
11904181001 Diversion point 1737.01 203.28 1159002 786846
11904181002 Diversion point 1737.49 202.78 1159615 786703
11904181101 Other secondary 1746.16 199.57 1163125 784291
11904181201 Other secondary 1740.43 199.73 1162997 784135
11904187001 Diversion point 227.76 222.86 1140268 791479
11904202301 Other secondary 17.86 228.45 1141757 807437
11904211301 Other secondary 5.51 286.50 1114689 846549
11904211302 Other secondary 5.53 286.39 1114800 846590
166
11904211303 Other secondary 5.62 286.05 1115203 846434
11904211304 Other secondary 0.68 286.08 1115288 846109
11904211305 Other secondary 0.60 286.30 1115053 845945
11904211306 Other secondary 0.57 286.59 1114999 845751
11904211307 Other secondary 0.37 286.95 1114431 846235
11904294001 Diversion point 7.20 203.69 1166457 794423
11904294301 Other secondary 7.19 203.74 1166458 794427
11904350301 Other secondary 0.36 223.19 1163292 831390
11904350302 Other secondary 0.52 223.01 1163405 831104
11904361101 Other secondary 17.20 199.05 1166855 808414
11904361201 Other secondary 16.56 199.68 1166052 808662
11904362001 Diversion point 16.20 199.99 1165663 808833
11904362002 Diversion point 16.22 199.79 1165859 808695
11904367001 Diversion point 753.56 272.24 1106166 805791
11904407001 Diversion point 2232.39 142.88 1194450 758740
11904434001 Diversion point 800.70 254.93 1115447 796002
11904440301 Other secondary 7.79 229.50 1142281 810230
11904484001 Diversion point 2083.98 156.01 1186467 759090
11904490001 Diversion point 2094.01 153.33 1186649 756476
11904495101 Other secondary 1903.77 185.65 1174422 781282
11904495201 Other secondary 1902.30 186.46 1173701 781638
11904496001 Diversion point 14.01 201.20 1164274 808422
11904496301 Other secondary 14.01 201.20 1164270 808421
11904497101 Other secondary 16.56 199.68 1166054 808662
11904497201 Other secondary 15.52 200.21 1165396 808787
11904497401 Other secondary 0.04 199.92 1165798 808668
11904498001 Diversion point 13.20 202.07 1162996 808563
11904498002 Diversion point 13.51 201.82 1163413 808395
11904499001 Diversion point 13.65 201.58 1163758 808329
11904503101 Other secondary 2094.12 153.18 1186760 756352
11904503201 Other secondary 2093.22 153.71 1186194 756346
11904510301 Other secondary 0.25 250.26 1146855 828366
11904510302 Other secondary 0.43 250.13 1146948 828187
11904510303 Other secondary 0.09 250.23 1146950 828374
11904512001 Diversion point 3452.55 112.47 1218649 747134
11904536101 Other secondary 2146.92 148.95 1189994 755265
11904536102 Other secondary 2147.35 148.49 1190392 755630
11904536201 Other secondary 2146.89 149.22 1189770 755123
11904536202 Other secondary 2147.29 148.73 1190211 755425
11904538001 Diversion point 2152.60 146.24 1191691 757476
167
11904538002 Diversion point 2152.31 146.75 1191034 757338
11904561001 Diversion point 833.87 134.00 1203831 760452
11905002001 Diversion point 2275.38 132.42 1203408 754443
11905043001 Diversion point 3572.32 107.80 1221272 744264
11905044001 Diversion point 3181.84 117.47 1215573 748904
11905062001 Diversion point 2146.92 148.95 1190005 755273
11905079001 Diversion point 3875.00 72.57 1248167 723225
11905097001 Diversion point 55.87 348.06 1068536 847901
11905126001 Diversion point 1902.42 186.25 1173952 781743
11905126002 Diversion point 1903.29 186.01 1174242 781734
11905171101 Other secondary 2027.34 170.39 1179110 770054
11905171201 Other secondary 2026.15 172.23 1178409 771390
11905182001 Diversion point 633.63 170.62 1187349 794308
11905194101 Other secondary 1941.06 180.07 1176627 776007
11905194201 Other secondary 1941.00 180.37 1176449 776364
11905202101 Other secondary 2083.95 156.06 1186460 759181
11905202201 Other secondary 2083.94 156.14 1186496 759281
11905211001 Diversion point 860.73 243.73 1125484 798592
11905211401 Other secondary 0.00 243.66 1125710 798506
11905211402 Other secondary 0.07 243.34 1125822 798221
11905214001 Diversion point 773.15 144.52 1199822 768317
11905218001 Diversion point 721.82 158.02 1194115 783360
11905218002 Diversion point 721.84 157.89 1194129 783238
11905220001 Diversion point 3875.01 72.52 1248273 723224
11905224101 Other secondary 480.14 182.52 1181169 805054
11905224201 Other secondary 478.54 183.25 1181319 805847
11905239001 Diversion point 2156.11 144.08 1192981 758617
11905243001 Diversion point 13.52 179.92 1176820 775865
11905262001 Diversion point 180.55 226.16 1153055 804681
11905264001 Diversion point 1940.71 181.29 1176027 776810
11905265101 Other secondary 13.38 201.87 1163321 808433
11905265201 Other secondary 13.20 202.07 1162993 808565
11905266001 Diversion point 1737.48 202.83 1159665 786762
11905289001 Diversion point 26.38 219.91 1155791 799272
11905296001 Diversion point 2151.85 147.23 1190605 757053
11905298301 Other secondary 0.94 195.43 1170059 787082
11905298302 Other secondary 0.93 198.65 1169369 788162
11905298303 Other secondary 0.71 195.86 1170465 787613
11905306001 Diversion point 2242.05 136.81 1199665 754140
11905307001 Diversion point 1957.12 177.58 1176859 773362
168
11905308001 Diversion point 773.04 145.07 1200045 769088
11905313001 Diversion point 3705.51 90.27 1233170 729574
11905320001 Diversion point 2027.42 170.06 1178790 770120
11905323001 Diversion point 2152.35 146.58 1191207 757477
11905333001 Diversion point 2154.84 145.54 1192309 757089
11905333002 Diversion point 2154.88 145.37 1192406 757252
11905337001 Diversion point 3.50 223.57 1142671 799056
11905339001 Diversion point 1.31 336.83 1079179 835439
11905342301 Other secondary 61.56 346.93 1069981 847765
11905367101 Other secondary 3143.52 128.44 1207682 756027
11905367201 Other secondary 2286.53 129.75 1206346 755474
11905368101 Other secondary 3146.77 126.57 1208893 755341
11905368201 Other secondary 3143.40 128.90 1207047 756096
11905391001 Diversion point 104.02 220.75 1148415 800411
11905391002 Diversion point 104.06 220.65 1148417 800287
11905391003 Diversion point 108.39 219.88 1148609 799128
11905391004 Diversion point 110.83 218.69 1149548 797793
11905391005 Diversion point 112.58 217.16 1150355 796009
11905391301 Other secondary 104.02 220.70 1148415 800403
11905391302 Other secondary 108.58 219.65 1148861 798913
11905391501 Return flow 113.08 216.30 1151074 795017
11905391502 Return flow 106.08 220.25 1148494 799638
11905391503 Return flow 108.66 219.52 1149033 798800
11905391504 Return flow 111.17 217.99 1149608 796928
11905391505 Return flow 112.63 217.03 1150473 795850
11905395001 Diversion point 2033.19 167.61 1178612 767357
11905399001 Diversion point 4.52 130.18 1202050 735969
11905399301 Other secondary 4.52 130.12 1202066 735987
11905423001 Diversion point 0.10 260.33 1130092 827922
11905423301 Other secondary 0.06 260.70 1130274 828500
11905423302 Other secondary 0.18 259.57 1131044 828065
11905423303 Other secondary 0.06 260.09 1130225 827488
11905423304 Other secondary 0.10 260.33 1130091 827923
11905423401 Other secondary 0.00 259.74 1129784 827169
11905455001 Diversion point 2156.16 143.95 1193088 758581
11905469001 Diversion point 41.99 257.08 1133850 824171
11905469002 Diversion point 41.99 257.08 1133850 824171
11905469301 Other secondary 41.99 257.08 1133850 824171
11905478001 Diversion point 3873.42 74.52 1245536 722560
11905478401 Other secondary 0.00 75.16 1245398 722868
169
11905489004 Diversion point 4164.34 13.48 1297679 708456
11905499001 Diversion point 2031.18 169.05 1178765 768781
11905503001 Diversion point 24.89 248.68 1144933 822220
11905503301 Other secondary 24.89 248.68 1144932 822221
11905517001 Diversion point 176.57 242.25 1134388 806721
11905517401 Other secondary 0.00 242.41 1134378 806306
11905532001 Diversion point 2152.42 146.32 1191433 757606
11905549001 Diversion point 13.33 246.80 1124055 801492
11905549002 Diversion point 13.73 246.15 1123969 800819
11905549003 Diversion point 17.31 242.28 1126849 797207
11905549301 Other secondary 13.34 246.74 1124105 801471
11905549302 Other secondary 13.73 246.15 1123971 800819
11905559001 Diversion point 684.03 161.18 1192555 787121
11905577001 Diversion point 1727.09 204.05 1157963 786756
11905577401 Other secondary 0.00 204.11 1158105 786559
11905587001 Diversion point 2068.16 159.04 1184282 761639
11905596001 Diversion point 960.21 228.36 1136359 789386
11905598001 Diversion point 1.54 238.88 1129432 795549
11905598301 Other secondary 1.23 238.94 1129430 795556
61901142001 Diversion point 8.05 289.39 1111618 852642
61901143001 Diversion point 19.50 282.52 1118865 851254
61901143002 Diversion point 19.50 282.52 1118867 851254
61901143301 Other secondary 19.50 282.52 1118858 851254
61901144001 Diversion point 8.20 284.43 1116988 846388
61901144301 Other secondary 8.20 284.43 1116988 846388
61901144302 Other secondary 8.60 283.83 1117759 846412
61901144303 Other secondary 4.32 283.92 1117866 845827
61901145301 Other secondary 15.06 276.87 1124928 841457
61901146001 Diversion point 285.44 210.91 1168837 821918
61901146002 Diversion point 285.58 210.70 1169021 821710
61901146003 Diversion point 285.64 210.48 1169280 821758
61901148001 Diversion point 617.82 173.01 1186846 796251
61901149001 Diversion point 618.02 172.49 1187210 795743
61901150001 Diversion point 633.92 169.65 1188314 793754
61901151001 Diversion point 635.26 169.10 1188187 793095
61901152001 Diversion point 646.76 167.82 1188574 792033
61901153001 Diversion point 647.35 166.49 1190110 791647
61901154001 Diversion point 652.39 165.36 1190274 790651
61901155001 Diversion point 654.15 164.68 1190837 789921
61901156001 Diversion point 655.42 163.50 1191464 788997
170
61901157001 Diversion point 683.24 162.21 1192043 788250
61901157002 Diversion point 683.27 162.10 1192034 788155
61901158001 Diversion point 684.06 160.98 1192651 786870
61901159001 Diversion point 684.67 160.76 1192729 786464
61901160001 Diversion point 727.68 156.51 1194780 781500
61901161001 Diversion point 747.97 151.64 1197466 776288
61901162001 Diversion point 749.42 150.02 1196952 774116
61901163001 Diversion point 5.59 149.41 1195993 773267
61901163002 Diversion point 755.53 149.05 1196328 772981
61901163301 Other secondary 5.12 149.35 1195965 773296
61901164001 Diversion point 759.10 147.68 1197569 771310
61901165001 Diversion point 762.41 147.42 1197577 771010
61901166001 Diversion point 762.46 147.29 1197670 770842
61901167001 Diversion point 807.79 143.32 1199561 766768
61901168001 Diversion point 833.00 134.71 1202860 760770
61901168002 Diversion point 829.22 135.42 1202111 760630
61901168003 Diversion point 827.84 136.00 1202542 761154
61901169301 Other secondary 50.75 278.05 1123100 847674
61901170001 Diversion point 6.38 205.74 1161904 812289
61901170301 Other secondary 6.37 205.74 1161914 812305
61901171001 Diversion point 481.77 180.35 1182569 802231
61901171002 Diversion point 481.75 180.30 1182499 802300
61901931001 Diversion point 104.09 220.57 1148433 800230
61901931301 Other secondary 104.09 220.57 1148432 800234
61901933001 Diversion point 108.39 219.88 1148608 799128
61901933002 Diversion point 108.39 219.88 1148608 799128
61901942001 Diversion point 108.39 219.88 1148609 799128
61901942301 Other secondary 108.58 219.65 1148864 798911
61901944001 Diversion point 110.88 218.61 1149627 797714
61901951301 Other secondary 1.64 215.69 1149977 794012
61901959001 Diversion point 358.25 212.48 1152398 790996
61901960001 Diversion point 135.98 240.50 1151814 817946
61901962001 Diversion point 166.35 232.08 1152920 809670
61901965001 Diversion point 184.56 222.24 1152655 801933
61901966001 Diversion point 358.25 212.48 1152393 790997
61901966301 Other secondary 358.25 212.48 1152395 790997
61902019001 Diversion point 358.25 212.48 1152388 790998
61902019301 Other secondary 358.25 212.48 1152391 790997
61902103001 Diversion point 48.22 367.52 1055445 855295
61902103002 Diversion point 50.91 367.36 1055665 855323
171
61902103003 Diversion point 10.18 367.59 1055462 856436
61902103004 Diversion point 10.31 367.44 1055642 856318
61902103005 Diversion point 10.36 367.31 1055683 856147
61902103006 Diversion point 10.40 367.20 1055710 855973
61902103007 Diversion point 10.43 367.07 1055759 855774
61902104101 Other secondary 92.07 356.67 1063488 855944
61902104201 Other secondary 67.29 361.53 1060406 855674
61902105001 Diversion point 78.15 360.23 1061582 854808
61902105002 Diversion point 4.66 360.36 1061581 854691
61902105003 Diversion point 93.73 356.23 1063867 855397
61902105301 Other secondary 4.40 360.79 1061434 854176
61902105302 Other secondary 0.16 360.82 1061724 854116
61902105303 Other secondary 4.66 360.42 1061581 854684
61902106301 Other secondary 9.81 360.15 1060863 857830
61902107001 Diversion point 95.12 355.15 1065312 855072
61902108001 Diversion point 5.37 360.01 1062450 860138
61902108002 Diversion point 5.50 359.88 1062515 859966
61902108003 Diversion point 5.61 359.62 1062808 859822
61902108004 Diversion point 5.80 359.41 1063006 859614
61902109001 Diversion point 158.56 346.00 1071773 848957
61902110001 Diversion point 158.82 345.62 1071693 848335
61902111001 Diversion point 1.54 362.66 1053860 844216
61902111301 Other secondary 1.57 362.45 1054123 844092
61902112001 Diversion point 5.60 356.96 1059800 846282
61902113001 Diversion point 29.63 355.98 1061173 846138
61902114001 Diversion point 1.49 357.95 1060383 848317
61902114002 Diversion point 1.60 357.61 1060734 847957
61902114003 Diversion point 1.16 357.27 1061557 848223
61902115001 Diversion point 4.03 356.36 1061868 847394
61902116001 Diversion point 42.22 353.48 1063896 846370
61902116002 Diversion point 41.99 354.07 1063374 846005
61902116301 Other secondary 42.31 353.41 1063977 846333
61902117001 Diversion point 234.39 341.77 1074945 847022
61902117002 Diversion point 234.32 341.93 1074779 846948
61902118001 Diversion point 1.10 340.92 1077959 849091
61902119001 Diversion point 304.04 329.93 1084576 841766
61902120001 Diversion point 316.43 329.12 1085471 841110
61902120002 Diversion point 319.06 328.81 1085867 840951
61902121001 Diversion point 4.94 333.47 1082165 838007
61902121002 Diversion point 4.94 333.42 1082174 838053
172
61902121003 Diversion point 4.41 333.74 1082124 837586
61902121004 Diversion point 5.09 333.18 1082291 838320
61902122001 Diversion point 323.93 326.95 1087990 839827
61902123001 Diversion point 395.25 319.75 1092914 839267
61902123002 Diversion point 395.36 319.49 1093035 838983
61902123003 Diversion point 395.47 319.04 1093645 838783
61902124001 Diversion point 6.91 323.62 1090352 836377
61902125001 Diversion point 6.94 323.57 1090427 836391
61902126001 Diversion point 415.05 317.07 1095445 839428
61902126002 Diversion point 413.16 317.29 1095284 839219
61902127001 Diversion point 415.10 316.84 1095595 839701
61902128001 Diversion point 1.72 322.39 1099362 848270
61902128301 Other secondary 1.72 322.44 1099362 848275
61902129001 Diversion point 9.99 321.54 1098693 847266
61902129301 Other secondary 9.99 321.54 1098692 847265
61902130001 Diversion point 648.84 286.46 1106384 816556
61902130002 Diversion point 633.63 291.06 1103163 819839
61902130301 Other secondary 633.63 291.06 1103163 819839
61902130302 Other secondary 648.84 286.46 1106384 816556
61902131002 Diversion point 648.84 286.46 1106384 816556
61902132901 Other secondary 648.84 286.46 1106384 816556
61902133001 Diversion point 683.42 275.93 1107069 808060
61902134001 Diversion point 762.58 271.98 1106178 805496
61902135001 Diversion point 4.11 307.85 1115051 835917
61902135301 Other secondary 4.11 307.85 1115046 835915
61902136001 Diversion point 4.95 306.79 1114905 834321
61902136301 Other secondary 4.95 306.74 1114905 834299
61902137301 Other secondary 784.87 263.09 1109243 799357
61902138001 Diversion point 789.15 259.36 1110513 795959
61902139001 Diversion point 789.21 259.15 1110864 795981
61902140001 Diversion point 805.97 251.88 1118753 796075
61902140002 Diversion point 806.71 250.77 1119572 796901
61902140003 Diversion point 806.93 250.14 1120445 796579
61902140004 Diversion point 807.15 249.83 1120872 796361
61902140005 Diversion point 807.27 249.56 1120993 796743
61902140006 Diversion point 11.23 251.44 1118809 797866
61902140007 Diversion point 12.01 249.93 1120224 797772
61902140008 Diversion point 24.32 249.07 1121082 797380
61902141001 Diversion point 2.82 251.31 1119704 800318
61902141002 Diversion point 2.89 251.24 1119771 800228
173
61902141301 Other secondary 2.85 251.31 1119719 800304
61902142001 Diversion point 24.33 249.02 1121152 797380
61902144001 Diversion point 833.05 247.05 1122723 797757
61902145001 Diversion point 956.84 230.61 1134794 790947
61902145002 Diversion point 956.87 230.56 1134736 790805
61902146001 Diversion point 957.92 229.96 1134657 790029
61902147001 Diversion point 14.96 236.90 1125491 789654
61902148001 Diversion point 30.78 234.80 1127746 788757
61902149001 Diversion point 207.84 228.89 1138192 796460
61902150001 Diversion point 226.26 224.24 1139138 791676
61902151001 Diversion point 235.99 219.29 1144410 790693
61902151002 Diversion point 3.44 219.96 1144865 793234
61902151301 Other secondary 3.44 219.89 1144905 793209
61902151501 Return flow 3.41 220.09 1144772 793296
61902152001 Diversion point 9.69 217.51 1146689 790513
61902152002 Diversion point 9.69 217.51 1146689 790512
61902153001 Diversion point 9.69 217.51 1146689 790515
61902153002 Diversion point 9.69 217.51 1146689 790514
61902153003 Diversion point 9.69 217.51 1146689 790514
61902153301 Other secondary 9.69 217.51 1146689 790513
61902153302 Other secondary 37.72 229.00 1147103 809856
61902153303 Other secondary 43.94 226.37 1145912 806491
61902153304 Other secondary 44.11 225.83 1145846 805856
61902153305 Other secondary 45.21 225.10 1146592 805078
61902153501 Return flow 34.94 230.91 1148333 812109
61902153502 Return flow 45.23 225.10 1146595 805054
61902153503 Return flow 160.33 236.59 1153877 813608
61902154001 Diversion point 9.69 217.51 1146689 790516
61902155001 Diversion point 1310.69 215.54 1148758 788152
61902156001 Diversion point 1345.46 210.31 1153210 786269
61902156002 Diversion point 1347.24 209.09 1154380 786417
61902156101 Other secondary 1347.24 209.09 1154375 786416
61902156201 Other secondary 1345.46 210.37 1153191 786268
61902157001 Diversion point 363.74 210.34 1153358 788301
61902158001 Diversion point 367.61 209.62 1154312 787807
61902158002 Diversion point 371.72 209.28 1154628 787480
61902159001 Diversion point 371.83 209.13 1154589 787256
61902160001 Diversion point 1722.00 206.91 1156160 785426
61902161001 Diversion point 1727.23 203.76 1158423 786869
61902161002 Diversion point 1727.24 203.76 1158470 786872
174
61902161003 Diversion point 62.24 201.51 1164417 791527
61902161301 Other secondary 9.19 204.21 1158729 787850
61902161302 Other secondary 62.24 201.51 1164417 791527
61902161501 Return flow 0.40 203.16 1162956 791127
61902162002 Diversion point 62.24 201.51 1164417 791527
61902162301 Other secondary 62.24 201.51 1164417 791527
61902162302 Other secondary 1727.24 203.76 1158480 786870
61902162401 Other secondary 0.00 206.08 1165452 796961
61902163001 Diversion point 1749.79 197.17 1165204 783859
61902164001 Diversion point 94.21 193.73 1168694 785416
61902164002 Diversion point 1846.69 193.52 1168399 785067
61902165001 Diversion point 1846.79 193.05 1168658 784571
61902166001 Diversion point 1904.69 183.82 1174708 778923
61902167001 Diversion point 1904.75 183.60 1175029 779044
61902168001 Diversion point 0.28 185.52 1179506 781816
61902168301 Other secondary 0.31 185.47 1179538 781762
61902169001 Diversion point 1955.00 179.09 1177403 774843
61902169002 Diversion point 1955.13 178.65 1176795 774624
61902169003 Diversion point 1956.72 178.26 1176587 774131
61902170301 Other secondary 2.41 177.62 1172628 774962
61902171001 Diversion point 2033.69 166.32 1180185 767457
61902172001 Diversion point 2040.50 164.78 1181216 766300
61902173001 Diversion point 2046.99 164.37 1181703 765868
61902174001 Diversion point 2047.02 164.24 1181763 765680
61902175001 Diversion point 2047.42 163.65 1182322 765376
61902176101 Other secondary 2067.58 160.12 1184154 762607
61902176201 Other secondary 2067.49 160.46 1183971 763094
61902177001 Diversion point 2067.59 160.07 1184261 762608
61902178001 Diversion point 2067.65 159.78 1184639 762487
61902178002 Diversion point 2067.69 159.59 1184720 762184
61902179001 Diversion point 2068.17 158.96 1184343 761538
61902179002 Diversion point 2068.29 158.65 1184206 761052
61902180001 Diversion point 2068.17 158.96 1184352 761524
61902180002 Diversion point 2068.29 158.60 1184214 761040
61902181001 Diversion point 2077.55 157.46 1184791 760002
61902182001 Diversion point 2084.15 155.69 1186168 758768
61902183001 Diversion point 2093.19 153.86 1185976 756486
61902184001 Diversion point 2107.69 152.09 1187964 755979
61902184002 Diversion point 2107.39 152.30 1187624 755933
61902184003 Diversion point 2107.71 151.98 1188159 755933
175
61902185001 Diversion point 2108.05 151.16 1188362 754831
61902185002 Diversion point 2107.83 151.59 1188479 755493
61902186001 Diversion point 2239.06 140.56 1196581 756452
61902188001 Diversion point 2275.62 132.10 1203807 754576
61902189001 Diversion point 2285.31 131.01 1204877 755047
61902190001 Diversion point 3454.60 111.47 1219255 745963
61902191301 Other secondary 6.84 133.03 1195050 746268
61902192001 Diversion point 3670.47 96.21 1228693 735083
61902193001 Diversion point 3706.81 88.64 1234034 727757
61902194001 Diversion point 3706.92 88.33 1234459 727634
61902194002 Diversion point 3708.50 86.95 1236131 727188
61902195001 Diversion point 3708.63 86.39 1237031 727112
61902196001 Diversion point 3723.19 85.76 1236978 726229
61902196002 Diversion point 3723.20 85.63 1237148 726168
61902196003 Diversion point 3723.37 85.20 1237654 726599
61902196004 Diversion point 3723.67 84.19 1237673 725722
61902197001 Diversion point 3781.27 79.59 1240771 724050
61902198001 Diversion point 3792.29 76.19 1243287 723076
61902199001 Diversion point 3792.25 76.32 1243190 723159
61902199002 Diversion point 3792.40 75.89 1243646 722721
61902199003 Diversion point 3795.30 75.44 1244243 722652
61902199004 Diversion point 3795.40 74.97 1244990 722473
61904768002 Diversion point 891.52 235.69 1131395 794358
61904768301 Other secondary 50.83 233.99 1132547 794162
176
APPENDIX D: SAN JACINTO BASIN RESULTS
177
D.1 INTRODUCTION
The following appendix contains a table of watershed parameters for all of
the control points in the San Jacinto River basin. The table includes the control
point identification number, type of control point, drainage area in square miles,
average curve number in the drainage area, mean annual precipitation in inches
across the drainage area, and the x and y coordinates of the control point location
based on the TSMS Albers projection described in Chapter 3.
178
ID Type Area (mi
2
) CN Precip X-coord. Y-coord.
0 Stream gage 3977.81 68 46 1485002 845337
100 Return flow 0.05 70 51 1468217 850207
101 Return flow 3.86 84 51 1471652 850497
102 Return flow 3.89 84 51 1471656 850669
103 Return flow 4.04 85 51 1471642 850942
104 Return flow 992.69 78 46 1472090 851929
105 Return flow 0.26 81 51 1471950 862287
108 Return flow 91.19 81 48 1458004 847706
109 Return flow 2.49 86 51 1471481 849730
110 Return flow 987.96 78 46 1470921 851351
111 Return flow 2.47 86 51 1471464 849638
112 Return flow 987.04 78 46 1470129 851148
114 Return flow 993.13 78 46 1472268 852008
116 Return flow 2.05 78 51 1473116 851484
117 Return flow 7.67 81 50 1466640 851984
118 Return flow 768.75 79 46 1464142 852007
119 Return flow 91.01 81 48 1457869 847552
120 Return flow 612.94 77 45 1458442 849548
121 Return flow 609.32 77 45 1456606 849555
122 Return flow 0.18 80 51 1474654 849737
123 Return flow 0.41 77 51 1474834 850159
124 Return flow 88.79 80 48 1457605 846636
125 Return flow 3973.15 68 46 1481291 848333
126 Return flow 3968.64 68 46 1480544 850669
127 Return flow 1.56 85 51 1471709 848877
128 Return flow 0.41 87 50 1466239 854382
130 Return flow 0.75 77 50 1464927 851504
132 Return flow 983.65 78 46 1467115 851986
133 Return flow 2.03 74 46 1427935 838574
134 Return flow 2.16 73 46 1418924 869483
135 Return flow 1.58 73 51 1473408 850733
136 Return flow 0.02 70 51 1474940 851579
137 Return flow 730.01 78 46 1461351 849765
138 Return flow 15.43 91 48 1454413 857689
140 Return flow 986.99 78 46 1469977 851166
141 Return flow 984.17 78 46 1467761 851393
142 Return flow 0.31 70 51 1467889 850584
143 Return flow 3958.58 68 46 1477130 851964
179
144 Return flow 768.66 79 46 1464013 851915
145 Return flow 1.16 67 51 1472307 860141
146 Return flow 1.16 67 51 1472306 860141
147 Return flow 488.28 65 45 1432312 909340
148 Return flow 29.24 66 50 1466984 857530
149 Return flow 6.15 81 50 1467256 848559
150 Return flow 0.01 92 51 1469024 844931
151 Return flow 8.83 87 50 1461651 848719
152 Return flow 93.95 80 46 1442313 845743
153 Return flow 1.75 75 46 1433299 836709
154 Return flow 2896.01 65 46 1475367 859408
155 Return flow 2.10 80 51 1472295 856932
156 Return flow 27.40 87 48 1460926 854358
157 Return flow 2.07 76 50 1462545 840413
158 Return flow 2.07 76 50 1462544 840413
159 Return flow 2900.61 65 46 1476569 858016
160 Return flow 0.08 92 49 1457245 850696
161 Return flow 22.52 75 46 1439294 837026
162 Return flow 1.89 82 50 1457809 840649
163 Return flow 5.92 79 47 1447225 875675
164 Return flow 34.96 72 46 1442928 873856
165 Return flow 2.26 59 49 1460066 866043
166 Return flow 8.64 71 45 1426410 841070
167 Return flow 23.24 72 46 1441061 874634
168 Return flow 17.79 73 45 1430634 842218
169 Return flow 4.05 79 47 1454751 872123
170 Return flow 1771.56 67 45 1457530 883115
171 Return flow 19.95 70 43 1417529 856766
172 Return flow 3.42 77 49 1462891 885449
173 Return flow 17.61 73 46 1439661 873353
174 Return flow 6.27 73 46 1430294 873564
176 Return flow 40.50 84 47 1455638 863018
177 Return flow 5.47 92 49 1457966 847796
178 Return flow 34.30 76 47 1443893 838221
179 Return flow 47.38 76 47 1450400 840393
180 Return flow 12.76 92 48 1453964 858464
181 Return flow 291.57 71 44 1428379 852504
182 Return flow 79.34 78 46 1439579 844599
183 Return flow 3.64 79 50 1461620 841484
184 Return flow 10.93 73 46 1437440 862242
180
185 Return flow 194.69 74 48 1461935 856106
186 Return flow 469.78 76 45 1453790 852682
187 Return flow 6.81 70 45 1424418 841784
188 Return flow 37.95 73 46 1434231 865498
189 Return flow 5.07 72 46 1437292 835377
190 Return flow 1.53 75 46 1428065 846490
191 Return flow 14.97 71 45 1426066 847333
192 Return flow 1.46 85 51 1471682 848506
193 Return flow 79.34 78 46 1439653 844657
194 Return flow 1.04 70 51 1471655 858591
195 Return flow 308.93 72 44 1433670 850983
196 Return flow 0.01 85 45 1422500 886031
197 Return flow 12.20 71 42 1402699 852974
198 Return flow 2.85 72 47 1454953 877218
199 Return flow 0.44 55 45 1425323 950497
200 Return flow 1.02 81 46 1421897 871806
201 Return flow 5.11 78 46 1423044 870484
202 Return flow 50.50 78 45 1431665 891909
203 Return flow 2.56 74 47 1440139 869575
204 Return flow 0.01 70 46 1430999 878593
205 Return flow 0.39 78 47 1439227 893471
206 Return flow 2.05 84 46 1433856 876013
207 Return flow 1.75 74 46 1426436 840717
208 Return flow 0.39 87 46 1436316 882168
209 Return flow 229.02 80 44 1425764 877499
210 Return flow 249.42 80 44 1433091 880370
211 Return flow 0.16 63 47 1446292 883570
212 Return flow 1.39 71 47 1443907 883998
213 Return flow 2.30 73 43 1409659 853043
214 Return flow 0.26 70 47 1433808 869733
215 Return flow 0.08 78 46 1427675 863505
216 Return flow 1.03 73 46 1427501 872884
217 Return flow 282.62 80 44 1439015 883243
218 Return flow 14.58 70 43 1414429 856420
219 Return flow 1.54 70 45 1419011 859805
220 Return flow 16.16 68 50 1473726 870076
221 Return flow 33.87 63 46 1434759 894210
222 Return flow 765.03 71 44 1452141 883628
223 Return flow 247.80 80 44 1430972 879312
224 Return flow 7.87 79 46 1415460 865261
181
225 Return flow 20.56 74 45 1420612 863308
226 Return flow 0.08 56 49 1462369 878885
227 Return flow 22.15 75 46 1428856 866175
228 Return flow 0.07 70 46 1434201 834759
229 Return flow 0.92 70 46 1426746 870348
230 Return flow 42.25 73 46 1446864 873283
231 Return flow 0.02 70 43 1408185 856034
232 Return flow 2.45 70 45 1419923 846167
233 Return flow 15.63 75 45 1417068 864205
234 Return flow 2.44 70 44 1415463 858707
235 Return flow 1.72 72 50 1462631 859605
236 Return flow 22.18 71 44 1411768 862711
237 Return flow 0.72 64 47 1444630 887560
238 Return flow 2.97 81 45 1434114 885851
239 Return flow 284.31 80 44 1440574 883383
240 Return flow 0.87 70 46 1436804 873773
241 Return flow 24.39 70 42 1410910 854014
242 Return flow 4.93 70 43 1412593 849717
243 Return flow 16.42 73 46 1437206 872802
244 Return flow 4.51 71 45 1413786 864326
245 Return flow 13.48 74 46 1420488 866243
246 Return flow 283.17 80 44 1439181 883262
247 Return flow 1.36 70 43 1413674 857923
248 Return flow 3.70 85 45 1429746 882418
249 Return flow 2.36 72 45 1423375 848277
250 Return flow 3.15 70 45 1421803 842869
251 Return flow 9.71 80 46 1425368 869765
252 Return flow 10.07 72 46 1433539 873375
253 Return flow 0.84 70 46 1435398 876604
254 Return flow 12.42 78 46 1426657 869070
255 Return flow 0.15 70 47 1444787 875078
256 Return flow 3.43 63 47 1437517 901468
257 Return flow 1.99 76 46 1439057 877929
258 Return flow 1.08 85 47 1442576 878513
259 Return flow 0.45 71 45 1422624 844511
260 Return flow 3.29 71 49 1461862 895505
261 Return flow 9.05 72 46 1440297 876092
262 Return flow 2.36 85 47 1443603 880395
263 Return flow 1.24 85 47 1442916 879044
264 Return flow 30.33 71 42 1414219 851264
182
265 Return flow 9.57 60 46 1433518 900983
266 Return flow 0.11 85 47 1442457 878265
267 Return flow 22.94 66 50 1467093 860966
268 Return flow 6.26 78 46 1418150 867835
269 Return flow 0.73 70 47 1445776 874269
270 Return flow 229.48 80 44 1426239 877245
271 Return flow 18.83 74 45 1419043 864085
272 Return flow 2.71 73 47 1440316 869485
273 Return flow 85.02 70 42 1410597 847442
274 Return flow 0.17 85 46 1411484 876733
275 Return flow 5.51 80 46 1416980 868695
276 Return flow 83.92 70 42 1409288 847813
277 Return flow 0.44 70 46 1429727 870386
278 Return flow 262.87 80 44 1434065 881260
279 Return flow 21.98 75 46 1428751 866279
280 Return flow 10.32 71 46 1422823 853395
281 Return flow 91.19 81 48 1458007 847710
1001 WQS point 2900.72 65 46 1476415 857860
1002 WQS point 2837.05 65 46 1468896 871810
1003 WQS point 393.00 61 48 1466049 889804
1004 WQS point 998.36 64 45 1455843 883767
1005 WQS point 3977.76 68 46 1484909 845584
1006 WQS point 1036.64 78 47 1474131 854551
1007 WQS point 771.83 79 46 1466349 852413
1008 WQS point 770.59 71 44 1455791 883707
1009 WQS point 328.47 79 44 1451346 883556
1010 WQS point 374.83 60 48 1465539 889624
1011 WQS point 157.08 58 49 1464182 893633
1012 WQS point 450.02 65 45 1425469 918533
1013 WQS point 461.21 75 45 1448951 853857
1014 WQS point 345.79 73 44 1442721 853142
1015 WQS point 276.38 64 44 1420497 905397
1016 WQS point 124.26 72 47 1460105 863026
1017 WQS point 110.46 81 47 1446801 855068
10061 WQS point 4.25 85 51 1471997 851754
10071 WQS point 15.97 89 50 1461168 849763
8067650 Stream gage 456.86 65 45 1427618 916968
8068000 Stream gage 828.74 64 45 1436252 906511
8068500 Stream gage 403.28 65 44 1438865 891717
8068740 Stream gage 131.09 80 43 1412481 873803
183
8069000 Stream gage 284.13 80 44 1439928 883427
8070000 Stream gage 324.58 61 47 1469702 918147
8070500 Stream gage 105.35 61 47 1451025 908779
8071000 Stream gage 117.42 56 49 1464036 906351
8071500 Stream gage 2813.56 65 46 1468754 880083
8073500 Stream gage 285.28 71 44 1424110 852342
8074000 Stream gage 346.06 73 44 1443140 852970
8074500 Stream gage 86.76 78 47 1444175 854631
8075000 Stream gage 94.41 80 46 1443076 845934
8075500 Stream gage 65.80 78 48 1455046 843845
8076000 Stream gage 63.94 75 47 1452208 870879
11004038001 Diversion point 1.78 63 47 1432042 914418
11004038301 Other secondary 1.78 63 47 1432042 914418
11004066001 Diversion point 27.36 71 44 1415727 860289
11004066401 Other secondary 0.00 59 45 1415879 860992
11004066402 Other secondary 0.01 65 45 1415764 860808
11004188001 Diversion point 9.55 62 45 1428909 900869
11004188301 Other secondary 9.55 62 45 1428907 900871
11004248001 Diversion point 3.20 60 47 1432753 921895
11004248301 Other secondary 3.20 60 47 1432753 921895
11004248401 Other secondary 0.01 84 47 1432356 921715
11004255301 Other secondary 0.20 74 47 1435040 930196
11004255302 Other secondary 0.16 83 47 1434530 930620
11004255303 Other secondary 0.06 56 47 1434367 929531
11004309301 Other secondary 0.13 56 47 1440797 937503
11004309302 Other secondary 0.20 55 47 1440884 936940
11004375001 Diversion point 33.42 77 46 1443428 837534
11004375501 Return flow 33.43 77 46 1443455 837567
11004523301 Other secondary 0.20 59 46 1426150 925244
11005055001 Diversion point 297.86 80 44 1443230 883601
11005055002 Diversion point 300.19 80 44 1444970 883931
11005055401 Other secondary 0.00 59 47 1443390 883521
11005055402 Other secondary 0.00 59 47 1444792 883862
11005191001 Diversion point 996.28 78 46 1473170 853020
11005191501 Return flow 996.27 78 46 1473041 852885
11005209001 Diversion point 39.64 74 46 1436077 864824
11005209401 Other secondary 0.00 92 47 1436129 865438
11005209402 Other secondary 0.01 92 47 1435948 865560
11005209403 Other secondary 0.04 88 47 1436142 865855
11005209404 Other secondary 0.00 72 47 1436395 865717
184
11005209405 Other secondary 0.00 72 47 1436429 865454
11005257001 Diversion point 287.38 71 44 1425810 852287
11005257401 Other secondary 0.08 90 46 1426638 852675
11005257501 Return flow 287.49 71 44 1425969 852651
11005261301 Other secondary 0.09 63 46 1431982 931263
11005299001 Diversion point 2900.72 65 46 1476357 857801
11005311001 Diversion point 53.10 74 45 1432522 842704
11005311401 Other secondary 0.00 85 46 1432386 842959
11005311402 Other secondary 0.00 92 46 1432644 842815
11005311403 Other secondary 0.00 92 46 1432709 842946
11005332001 Diversion point 28.05 71 44 1416141 859359
11005332401 Other secondary 0.00 59 45 1416973 859284
11005334001 Diversion point 2901.02 65 46 1476007 857364
11005334501 Return flow 2901.02 65 46 1476007 857364
11005336101 Other secondary 314.15 72 44 1436029 853763
11005336201 Other secondary 310.89 72 44 1434611 852732
11005336401 Other secondary 0.00 92 47 1435286 852977
11005336402 Other secondary 0.00 92 47 1435867 853656
11005340001 Diversion point 2900.34 65 46 1476475 858707
11005353001 Diversion point 711.52 78 46 1460060 849453
11005353501 Return flow 711.51 78 46 1459956 849374
11005362001 Diversion point 4.62 75 46 1429657 841228
11005362002 Diversion point 4.42 74 46 1433524 837936
11005362501 Return flow 4.44 74 46 1433561 837759
11005363001 Diversion point 289.75 71 44 1427390 852609
11005363501 Return flow 291.24 71 44 1427698 852506
11005408301 Other secondary 0.75 67 44 1415485 894869
11005408302 Other secondary 2.11 73 44 1415889 895310
11005430001 Diversion point 611.61 77 45 1458023 849835
11005430002 Diversion point 612.86 77 45 1458207 849765
11005432001 Diversion point 609.30 77 45 1456573 849569
11005432002 Diversion point 609.30 77 45 1456512 849595
11005432003 Diversion point 609.28 77 45 1456448 849624
11005436001 Diversion point 5.79 79 49 1462087 884330
11005436301 Other secondary 5.01 78 49 1461681 884719
11005436302 Other secondary 5.04 78 49 1461893 884514
11005436303 Other secondary 7.71 79 49 1462173 883664
11005436404 Other secondary 0.00 59 49 1462155 884327
11005437301 Other secondary 4.84 78 49 1461606 884863
11005471301 Other secondary 4.99 57 44 1407995 895119
185
11005498001 Diversion point 341.09 61 47 1468748 913112
11005505001 Diversion point 8.95 81 46 1439269 844150
11005505002 Diversion point 70.21 78 46 1439239 844182
11005505401 Other secondary 0.00 92 47 1438886 843512
11005505402 Other secondary 0.00 92 47 1439042 843257
11005507001 Diversion point 200.72 74 48 1465260 853589
11005514001 Diversion point 2.67 85 43 1402781 874202
11005514002 Diversion point 3.38 85 43 1403205 873859
11005514003 Diversion point 3.41 85 43 1403532 873526
11005514401 Other secondary 0.00 85 44 1403324 873105
11005522001 Diversion point 1.49 85 51 1471729 848658
11005560001 Diversion point 201.04 74 48 1465613 853143
11005565001 Diversion point 50.95 74 46 1437482 862772
11005565401 Other secondary 0.00 70 47 1437113 862732
11005572301 Other secondary 0.10 55 44 1405358 894201
11005576301 Other secondary 1.95 61 45 1418714 901183
61003927301 Other secondary 1.66 65 45 1424569 953542
61003928301 Other secondary 2.25 64 45 1424239 952698
61003929301 Other secondary 4.16 61 45 1422768 950609
61003930001 Diversion point 3.03 71 45 1427256 951969
61003930301 Other secondary 3.03 71 45 1427256 951969
61003930302 Other secondary 3.88 70 45 1426604 951393
61003930303 Other secondary 4.97 68 45 1426351 950874
61003931301 Other secondary 14.72 61 45 1427348 946617
61003932301 Other secondary 0.44 55 44 1414432 930611
61003933301 Other secondary 0.97 58 44 1415113 930527
61003934301 Other secondary 0.30 62 44 1412790 928266
61003935301 Other secondary 0.45 71 47 1429704 926374
61003936301 Other secondary 0.08 79 45 1417307 921465
61003936302 Other secondary 0.40 71 45 1417350 921625
61003937301 Other secondary 0.82 57 45 1419198 919114
61003938301 Other secondary 1.05 58 45 1419156 919712
61003939301 Other secondary 1.12 65 45 1421450 918695
61003939302 Other secondary 0.35 68 45 1421561 918243
61003939303 Other secondary 0.09 76 45 1421948 917906
61003940301 Other secondary 1.86 61 45 1425558 916419
61003941001 Diversion point 6.06 63 43 1390368 923511
61003941301 Other secondary 6.06 63 43 1390368 923511
61003942301 Other secondary 0.14 87 44 1408659 917543
61003942302 Other secondary 0.02 89 44 1408630 917729
186
61003942303 Other secondary 0.07 81 44 1409119 917720
61003942304 Other secondary 0.02 78 44 1409197 917914
61003943301 Other secondary 0.03 62 44 1413353 913665
61003944301 Other secondary 0.63 74 45 1420197 915295
61003945301 Other secondary 1.80 58 45 1419884 912944
61003946301 Other secondary 1.29 62 45 1422580 914296
61003947301 Other secondary 3.03 59 45 1424265 912736
61003948301 Other secondary 4.51 61 47 1434383 921538
61003948302 Other secondary 0.16 55 47 1433918 922154
61003949301 Other secondary 0.48 73 47 1438104 905084
61003950301 Other secondary 0.85 67 47 1438472 914969
61003951301 Other secondary 0.42 77 47 1441591 905176
61003952001 Diversion point 0.12 86 43 1400274 888592
61003952301 Other secondary 0.12 86 43 1400274 888592
61003953301 Other secondary 0.64 56 43 1391859 905539
61003954301 Other secondary 0.14 74 44 1404507 898350
61003955301 Other secondary 5.69 60 44 1412378 894181
61003955302 Other secondary 0.93 55 44 1412451 894012
61003956101 Other secondary 0.33 82 44 1401908 906109
61003957301 Other secondary 0.35 83 44 1413157 899034
61003957302 Other secondary 0.06 84 44 1412816 899158
61003957303 Other secondary 0.45 81 44 1413280 899058
61003957304 Other secondary 0.36 83 44 1413199 899046
61003958301 Other secondary 75.04 61 44 1421347 894103
61003959001 Diversion point 29.76 61 46 1434205 896869
61003959301 Other secondary 29.76 61 46 1434205 896869
61003960001 Diversion point 0.52 85 46 1434935 894798
61003960301 Other secondary 0.52 85 46 1434935 894798
61003960302 Other secondary 0.03 84 46 1435122 895280
61003961001 Diversion point 34.70 63 46 1434869 892890
61003962301 Other secondary 5.84 85 42 1389463 884089
61003963001 Diversion point 69.94 80 42 1397549 867733
61003963401 Other secondary 0.00 70 42 1397704 867279
61003964001 Diversion point 3.89 85 43 1400431 875312
61003964301 Other secondary 3.89 85 43 1400432 875312
61003965101 Other secondary 131.07 80 43 1412409 873864
61003965201 Other secondary 108.04 80 42 1403892 872491
61003965401 Other secondary 0.00 85 44 1404645 873392
61003965402 Other secondary 0.00 92 44 1406086 873573
61003965403 Other secondary 0.00 92 45 1408663 874042
187
61003965404 Other secondary 0.00 73 44 1404400 871430
61003966001 Diversion point 2.04 85 44 1405714 874952
61003966301 Other secondary 2.04 85 44 1405711 874956
61003967001 Diversion point 135.01 80 43 1413742 873379
61003968001 Diversion point 7.82 78 45 1427148 877764
61003968401 Other secondary 0.00 90 46 1427436 877537
61003969301 Other secondary 0.26 62 45 1436138 956094
61003969302 Other secondary 0.42 67 45 1436033 955995
61003969303 Other secondary 0.04 56 45 1436141 955727
61003970001 Diversion point 358.94 61 47 1470128 904910
61003970002 Diversion point 358.92 61 47 1470103 905124
61003971301 Other secondary 0.36 59 47 1439336 934003
61003972301 Other secondary 1.11 63 46 1433503 933109
61003973301 Other secondary 0.24 75 47 1433928 931069
61003974001 Diversion point 0.49 56 47 1438428 929407
61003974301 Other secondary 0.49 56 47 1438428 929407
61003975301 Other secondary 0.29 75 47 1440100 926592
61003976301 Other secondary 2.58 55 47 1442697 924603
61003977301 Other secondary 11.12 56 47 1447041 922496
61003978301 Other secondary 12.51 56 47 1447048 921059
61003979001 Diversion point 194.11 58 50 1479264 897316
61003979301 Other secondary 194.11 58 50 1479264 897316
61003979401 Other secondary 0.00 92 50 1480586 897074
61003980001 Diversion point 2813.61 65 46 1468759 879903
61003980401 Other secondary 0.00 92 50 1473860 881578
61003980402 Other secondary 0.00 70 50 1473822 881199
61003981301 Other secondary 0.37 64 50 1469132 868023
61003982001 Diversion point 86.87 70 42 1410838 847520
61003983001 Diversion point 1.40 70 44 1404930 866400
61003983401 Other secondary 0.02 70 43 1404419 865930
61003984001 Diversion point 2.79 74 45 1412562 867771
61003984002 Diversion point 2.92 74 45 1412856 867711
61003984003 Diversion point 5.59 79 46 1414188 867523
61003985001 Diversion point 344.44 73 44 1441159 852633
61003985401 Other secondary 0.01 91 48 1441124 852363
61003986001 Diversion point 345.45 73 44 1441849 852581
61003987001 Diversion point 0.18 92 48 1453298 852525
61003987002 Diversion point 468.62 76 45 1453003 852763
61003988001 Diversion point 713.67 78 46 1460965 849843
61003988501 Return flow 15.96 89 50 1461121 849708
188
61003989001 Diversion point 768.64 79 46 1463875 851834
61003990001 Diversion point 768.76 79 46 1464200 852034
61003991001 Diversion point 771.79 79 46 1465963 852420
61003992001 Diversion point 975.63 78 46 1466390 852389
61003992501 Return flow 7.66 81 50 1466528 851901
61003992502 Return flow 975.63 78 46 1466490 852323
61003992503 Return flow 7.57 81 50 1466490 851476
61003993001 Diversion point 985.83 78 46 1469853 851205
61003993501 Return flow 985.83 78 46 1469852 851205
61003994001 Diversion point 988.33 78 46 1471700 851904
61003994501 Other secondary 992.69 78 46 1472090 851929
61003994502 Other secondary 4.04 85 51 1471642 850942
61003994503 Other secondary 3.89 84 51 1471656 850669
61003994504 Other secondary 3.86 84 51 1471652 850497
61003995001 Diversion point 16.56 64 50 1465954 864347
61003995002 Diversion point 16.56 64 50 1465954 864347
61003995301 Other secondary 16.56 64 50 1465954 864347
61003996001 Diversion point 3959.26 68 46 1477400 851759
61003996501 Return flow 3959.42 68 46 1477640 851577
61004963001 Diversion point 450.02 65 45 1425454 918554
61004963301 Other secondary 450.02 65 45 1425455 918553
61004964001 Diversion point 2837.06 65 46 1468957 871753
61004964401 Other secondary 0.00 92 51 1479744 862136
61004965001 Diversion point 2837.06 65 46 1468958 871753
61004965301 Other secondary 2837.06 65 46 1468957 871753
61004966001 Diversion point 0.18 78 46 1425920 921884
61004966002 Diversion point 3.72 76 46 1427184 927247
61004966301 Other secondary 3.72 76 46 1427184 927247
189
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191
VITA
David Mason was born in Boca Raton, FL on May 23, 1976, the son of
Joseph Henry Mason and Elizabeth Ann Mason. After completing his work at St.
Edwards School in Vero Beach, FL, he entered Virginia Polytechnic Institute and
State University in Blacksburg, VA. He received a Bachelor of Science in Civil
Engineering from Virginia Tech in 1998. In August of 1998, he entered the
Graduate School at the University of Texas at Austin.
Permanent address: 5144 N. U.S. 1
Fort Pierce, FL 34946
This thesis was typed by the author.