The Science, Policy, and Economics of Achieving Stormwater Capture and Water Neutrality – A Case Study of the University of California, Irvine Campus
Stormwater is an overlooked source of freshwater in urban areas throughout southern California, including on college campuses. The University of California Stormwater Initiative is a multi-campus research effort to evaluate the feasibility of capturing and subsequently using stormwater runoff from the five southern UC campuses (UC Irvine, UC Los Angeles, UC Riverside, UC San Diego, and UC Santa Barbara). This Stormwater Initiative presentation will focus specifically on the concept of water neutrality at UC Irvine (how much can UCI rely on stormwater to satisfy its potable and non-potable water demand?) and a proposed stormwater capture project for the campus. The analysis blends stochastic hydrology (to predict volumes of runoff), water policy (to evaluate existing water portfolios and regulatory constraints), and economics (to achieve maximum environmental benefits for minimum cost). We assess two environmental benefits of stormwater capture, namely (1) the percent of runoff volume captured annually (and thus no longer discharged to nearby San Diego Creek), and (2) the percent of water demand that can be satisfied by captured stormwater annually. Our analysis also takes precipitation variability into account, comparing how a wet year versus a dry year affects the degree of environmental benefits delivered by the stormwater capture system. This presentation will walk audience members through the steps of conceptualizing a stormwater capture project, from initial predictions of runoff volume to understanding the economics, environmental benefits, and policy implications, using UCI as a case study. Audience members will also be introduced to the idea that water neutrality looks different at different scales, depending on where we draw the box (i.e., looking at the UCI campus in isolation versus including local water utilities and ecosystems). While the focus is on the UC Irvine campus, the interdisciplinary science, engineering, and policy analysis, within the larger context of a water neutrality framework, will inform stormwater capture projects at any scale or geographic location. Audience members will be engaged and prompted to think about how to apply a similar analysis to their own stormwater projects. This presentation is well aligned with the conference theme and CASQA vision, as its focus is on establishing stormwater as a vital resource at UC Irvine by “connecting the drops” of science, policy, and economics.