Suchergebnisse

Includes bibliographical references. ; 2020 Spring. ; Rainwater harvesting (RWH) is a localized renewable water supply alternative that minimizes the necessary resources for beneficial use. Estimates for RWH potential vary, and past studies conclude that accurate modeling depends on variables like precipitation, demand, and tank volume. In Colorado, RWH potential is limited by the high irrigation rates required by traditional turfgrass landscaping in the semi-arid climate. Additionally, RWH storage volume is strictly regulated under Colorado water law for both residential rooftop runoff capture (decentralized) and neighborhood-scale stormwater harvesting (centralized). Historically, legal storage limitations have effectively prohibited RWH, but legislation in the last decade has increased viability of, and interest in, RWH as a renewable supply source. However, despite recent progress toward RWH, it remains unclear whether Colorado has appropriate policy, infrastructure, and climate conditions to develop RWH as viable water supply. This research furthers our understanding of the practical viability of RWH in Colorado and finds that current allowable harvesting practices can provide for residential irrigation when demand is limited by landscaping area and vegetation type. Established and novel modeling methodologies are used to evaluate water quality treatment for stormwater harvesting, to develop estimates of allowable harvest volume for centralized harvesting, and to estimate supply yield potential for both centralized and decentralized RWH. We tested the sufficiency of one- and twoparameter linear models for predicting stormwater treatment effluent quality and conclude that monitoring studies should more thoroughly report parameters to support more complex treatment models for better treatment estimates. A state-approved water rights accounting method and tool were developed to support centralized RWH pilot projects; the tool lowers the barrier to entry for pilot participants and represents an innovative expansion of Colorado's water administration practices. Finally, the potential yield of residential RWH was simulated with different supply and demand variables. We conclude that RWH potential is most limited by irrigation demand, and that changes in precipitation and storage volume have the largest effect on increasing yield when irrigation demand is lowest.