Diffusion of innovations and decentralized green stormwater infrastructure : a case study of the headwaters of Waller Creek Watershed, Austin, Texas

This Report was undertaken as partial fulfillment of the requirements for the degree of a Master of Science in Community and Regional Planning and also as an investigation into how the City of Austin’s Watershed Protection Department (WPD) can advance the particular goals of their Pilot Project: “Rain Catcher”. The Report explores and discusses: 1) the ways in which infrastructure in cities has been regarded and constructed over time, 2) how these perspectives and approaches have influenced stormwater management in the United States, 3) what this has entailed in the case of Austin, Texas, specifically and 4) what are the current barriers and opportunities for the WPD Rain Catcher Pilot Project. With this Pilot Project, the WPD seeks to understand if installing green stormwater systems (e.g. rain gardens and cisterns) on private and public parcels is a feasible alternative service delivery model for stormwater management. To identify the potential barriers and opportunities (i.e financial, technical, cultural, etc.), this study conducted a survey of residents in the headwaters of Waller Creek. In order to interpret the survey results and provide recommendations to WPD, I applied the social science theory Diffusions of Innovations. Results of the survey indicate that the diffusion process of rain gardens and cisterns is in its early stages. Relatively few respondents had already adopted these green stormwater systems (GSI) at their residences and even fewer had familiarity with what constituted a rain garden. Despite this, there was a willingness by a majority of those surveyed to install GSI. The primary obstacles facing greater adoption expressed by residents are 1) cost 2) maintenance 3) help with installation. These practical barriers were also mirrored in people’s yard management: money, time, and knowledge were identified as the three primary reasons why respondents did not have their “ideal yard”. Currently, the majority of respondents do not manage yards that are eco-centric and instead prioritize convenience and keeping costs low. Notable distinctions were revealed between adopter categories (innovators, early adopters, late majority/laggards) however: innovators do value yards that are more eco-centric, ones that can provide a variety of ecosystem services. Additionally, innovators and early adopters had greater levels of education, were wealthier and younger. Diffusion of Innovation theory can provide a framework for the WPD to encourage the greater adoption of GSI. For example, tailoring these GSI to have greater “relative advantage” (i.e. by lessening yard management costs or maintenance needs) would encourage adoption. Reducing the “complexity” of these systems (either in how they are perceived or in terms of providing assistance in their installation, for example), will also help in this regard. To enable greater “compatibility” for GSI, in terms of cultural and social norms, could entail not only simplifying these systems but also promoting yard management practices that are more eco-centric. Finally, Diffusion of Innovation literature suggests that also providing more “trialability” and “observability” opportunities of rain gardens and cisterns will aid in their adoption.