For years, Californians have mismanaged the aquifers that supply the state with about 40 percent of its water supplies. Declining water levels from over-pumping have left less water for agriculture, urban, and other uses in many areas of the state.
But the problems do not stop with groundwater users. Groundwater and surface water are closely connected, so declining groundwater can reduce streamflow at critical times of the year, and can devastate rivers, streams, and wetlands. As groundwater levels drop, people who use surface water have less, but low flows can also leave fish gasping in dewatered streams. Oak forests and wetlands can wither and die. Water quality suffers.
Scientists have long understood that water filters into aquifers from streambeds and the ground surface, and that groundwater in turn contributes to the flow of many streams and wetlands. California water law, however, until recently neglected this reality, treating groundwater and surface water as separate.
A recent law provides an opportunity to address this disconnect, but findings from a recent UC Berkeley report make clear that tough action is required. The Sustainable Groundwater Management Act (SGMA) requires local governments to manage their groundwater resources sustainably. Among other benchmarks, the law charges groundwater agencies with avoiding surface water depletion.
This requirement is a dramatic change. California law recognizing surface water-groundwater interconnections is a bit like the Berlin Wall coming down: immense possibilities emerge from rebuilding connections. However, just as the Berlin Wall’s fall began a difficult reunification process, California now faces the challenge of reconciling two long-separated and sometimes conflicting aspects of water management.
Water rights systems for groundwater and surface water are largely separate. The new law says surprisingly little about how to square their differences. The goals of groundwater users, surface water users, and environmental protection can appear to conflict with one another, creating acute tensions where groundwater pumping affects surface water flows and habitats.
But the opportunities are immense. SGMA provides a process and a forum for sorting out groundwater-surface water conflicts for the first time in California’s history. It just might work if everyone comes to the table.
Our main conclusion is that a “go it alone” approach will no longer work: using groundwater without considering the impacts on ecosystems and surface water users will no longer fly in California. This fact alone could profoundly change California water management. The integration of these two dimensions of California’s water resources may force the siloed interests that have traditionally worked in opposition to come together.
The upside is the opportunity to unleash innovation and craft creative, win-win-win solutions such as new ways to recharge more water into the ground, or to break out of years of narrow thinking and truly operate water systems at watershed scales.
Effective integrated management of groundwater and surface water is simultaneously one of the most important and most difficult challenges facing California. With broad integration, local creativity and ample state support, a sustainable water future above and below ground may just be attainable. It will take time, patience, and good faith effort, but it will be worth it. After all, a reunited Berlin was worth it, too.
As originally published in The Mercury News by Dave Owen, Alida Cantor and Michael Kiparsky on May 9, 2018