Lessons from California’s 2012–2016 Drought

Abstract

California's 5-year drought has ended, even as its aftermath lingers. From 2012-2016 much or all of California was under severe drought conditions, with greatly diminished precipitation, snowpack, and streamflow and higher temperatures. Water shortages to forests, aquatic ecosystems, hydroelectric power plants, rural drinking water supplies, agriculture, and cities caused billions of dollars in economic losses, killed millions of forest trees, brought several fish species closer to extinction, and caused inconvenience and some expense to millions of households and businesses. The drought also brought innovations and improvements in water management, some of which will better prepare California for future droughts. This paper summarizes the magnitude and impacts of the 2012-2016 California drought. The paper then reviews innovations arising from the drought in the larger historical context of water management in California. Lessons for California and for modern drought management are then discussed. Droughts in modern, well-managed water systems serving globalized economies need not be economically catastrophic, but will always have impacts and challenges, particularly for native ecosystems. In California and every other water system, droughts usefully expose weaknesses and inadequate preparation in water management. In this regard for California, managers of ecosystems and small rural water supplies had the most to learn.

Water resilience lessons from Cape Town's water crisis

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Does More Storage Give California More Water?

“…The warm‐dry case employed effectively adds about a 30% scarcity, similar to the scarcity experienced in California's recent drought (Lund et al. ). In the end, optimal use only matters when demand exceeds supply, so insights from this case are intended to provide insights to system behavior under reasonable assumptions of substantial scarcity.…”

“…This system was designed based on historical hydrology and has performed reliably in historical extreme events, although growing populations and agricultural demands, exacerbated by extreme droughts and floods, are testing the system (Lund et al. ). The 12‐year period from 2006 to 2017 included three designated wet years — including one of the wettest on historical record (2017) following one of the driest periods (2012–2016).…”

Domestic well vulnerability to drought duration and unsustainable groundwater management in California’s Central Valley

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