When it comes to water conservation in cities that depend on wastewater reuse, even the best intentions can have unintended consequences. That’s the main message to be gleaned from new findings from a team of water economists and engineers led by Kurt Schwabe, a professor of environmental economics and policy and the associate dean of the School of Public Policy at the University of California, Riverside.
Treated municipal wastewater has a broad variety of potential uses, the researchers noted. It can be applied to irrigated agriculture and golf courses, used to recharge groundwater, or supply critical flows to local streams and rivers that provide habitat and recreational services. In regions like Southern California, where most water is used for municipal purposes rather than agricultural ones, effluent — municipal wastewater that has been treated — flows from inland communities down the Santa Ana River Basin and toward the coast.
As a result of compliance with conservation measures through lower indoor water use, the amount of wastewater effluent was reduced. This reduction means less water for recycling and reuse — a source of water often thought of as drought-proof — and less water for stream augmentation, with a consequence of potentially impacting streamflow and downstream water quality, the researchers wrote.
Source: Water World
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