Urban water conservation strategies that reduce greenhouse gas emissions benefit health

Water use in California is intricately linked to energy use and greenhouse gas emissions: because most of California’s water is transported hundreds of miles, often over mountains and across deserts, the energy and carbon footprints are especially large. Consequently, water conservation strategies in California have significant potential to impact climate change and therefore human health through a variety of pathways. Here, we report the results of a comprehensive Health Impact Assessment (HIA) of urban water conservation methods in compliance with California Senate Bill x7-7.  These results are summarized by comparing the health impacts of status quo to two scenarios that could be implemented in response to California’s drought: (1) banning landscape irrigation, and (2) expanding use of alternative water sources (e.g., desalinated or recycled water). Out of the possible solutions studied, expansion of recycled water was found to be the most desirable, because it has large positive effects and small, manageable negative effects on water conservation, energy use and human health.