If the Sierra snowpack vanishes as feared, California will need ideas like this for water

Sacramento — which once only had to worry about seasonal floods — now worries each year about delivering water to its citizens in a hotter and drier California.

But there is a way for Sacramento to capture rain and snow, and for the broader region to keep surface reservoirs like Folsom and Oroville lakes nearly full. This same technique could help Sacramento capture enough water to share with neighboring areas in dry years, as well as to store it when we need it most.

It’s called groundwater banking. The need for it will only become more urgent as the Sierra snowpack starts to disappear.

According to a recent study by researchers at the Lawrence Berkeley National Laboratory, snowpack in the Sierra Nevada mountains will become increasingly scarce, leading to decades-long stretches without snowfall by the 2050s.

Through groundwater banking, providers can divert water into an underground aquifer that is less dependent on seasonal rainfall and can be stored until it is needed.

State and local experts say major funding is needed for this strategy to take root in Sacramento. The Sacramento Regional Water Authority, a joint powers authority representing nearly two dozen local water providers, is seeking funding to capture rainfall and surface water that is currently lost from the Sierra snowpack and surface water reservoirs. It’s a promising plan that deserves consideration from lawmakers as California enters a future shaped by worsening climate change.

Sacramento would be following in the footsteps of others, such as the San Joaquin Valley and San Antonio, Texas, which is the largest city in the U.S. that relies solely on groundwater aquifers for its municipal supply.

An infusion of nearly $300 million could allow the regional water authority to rehabilitate and install new well systems and also solve some of California’s most persistent climate-related challenges.

Roseville is already delivering some bankable water to a small-scale groundwater banking system. Upgraded infrastructure would be able to increase the input from many of the other 20 water purveyors who are part of the regional authority, and help ameliorate snowpack changes impacting our region’s supply.

Banking into these aquifers would better capture water runoff from rain and snow that typically ends up in the sea, and withdraw the water when needed, mitigating environmental damage and the strain on consumers when conservation is needed. Capturing the spring melt could stave off the all-but-certain future of more drought-filled summers.

Experts say no solution will completely solve California’s worsening water woes. But the Sacramento Regional Water Authority, in coalition with the Sacramento Water Forum, could use groundwater banking to maximize the American River watershed and boost the ecological health of the Sacramento Valley and beyond, aiding more of California’s waterways.

Sacramento’s groundwater aquifers could be ideal for this strategy since the groundwater aquifers underneath Sacramento are in better condition than many others in the state.

California should maintain its conservation efforts, but conservation alone is not a realistic solution. Infrastructure investments for strategies like groundwater banking can strengthen the connections between water systems and help distribute more water in wet periods while allowing the use of groundwater during dry periods. It is a worthwhile expense to help maintain the flexibility to move between surface water reservoirs like Folsom Lake and underground basins that can hold twice as much to alleviate runoff losses.

Supporting our water districts will not only allow the residents of the Sacramento Valley to withstand future droughts, but also benefit water users throughout the state.

This story was originally published February 2, 2022 at 5:00 AM with the headline "If the Sierra snowpack vanishes as feared, California will need ideas like this for water."