California must embrace groundwater management, and expand it

By Sandi Matsumoto, Special to CalMatters

We all walk on water. Not literally, but most Californians do walk over the water stored in the aquifers beneath our feet. 

This unseen resource is groundwater, which provides 40% of our water supply in normal years, and up to 60% of our supply in times of drought.

With dry periods expected to increase in frequency and duration, groundwater is key to creating a more resilient water supply for drinking water, producing food, and sustaining our precious natural resources. Yet despite its importance, groundwater use in California has been largely unregulated.

Fortunately, this is about to change. 

This month marks the fifth anniversary of the signing of the Sustainable Groundwater Management Act. Under this act, groundwater users must come together to understand groundwater conditions and make hard decisions about how to sustain our groundwater supply.

Over the last five years, more than 250 groundwater sustainability agencies have formed to manage groundwater at the local level and dozens of groundwater sustainability plans are in progress. These plans will be implemented to achieve groundwater sustainability by 2042.

So what do we still need to make the Sustainable Groundwater Management Act a success?

First, local agencies need to engage disadvantaged communities that rely on shallow wells, as well as people who represent the plants and animals that rely on shallow sources of groundwater. These groups will be the first to feel the impact of declining groundwater levels, but too few agencies have meaningfully engaged them in decision making and planning.

The state should provide incentives, training and tools to help local agencies reach out to these underrepresented interests. Local agencies should provide them seats on boards and key committees. If agencies fail to adequately engage with them, the state should reject their plans. 

Second, academic institutions, non-governmental organizations and agencies should continue their work to reduce the time and cost of complying with the act. Currently, they are providing free resources on a diverse range of issues and providing feedback on draft plans to help local agencies identify and address deficiencies early.

Third, to achieve sustainable groundwater management, agencies will need to significantly increase water supplies through recharging aquifers and reducing groundwater use. Public funding and local investments should prioritize projects that provide benefits for multiple uses, including drinking water and nature.

The Nature Conservancy and the Colusa Groundwater Authority will soon pilot a project to recharge aquifers while providing seasonal wetlands for shorebirds. If successful, this project will serve as a model for how farmers can improve our groundwater supply while supporting the habitat needs of migratory birds.

Because agriculture relies upon groundwater, some landowners may decide to stop farming. To make this transition easier, the state should enable and incentivize alternative land uses, including the opportunity to return cultivated lands into wildlife habitat.

Finally, we need to expand groundwater regulation. Large areas, including the desert and areas dominated by volcanic rock, lack effective groundwater regulation today. Three-quarters of the groundwater-dependent ecosystems are in unregulated areas.

As the Sustainable Groundwater Management Act limits pumping, pressure will mount to find “new” sources of water in unregulated areas. Pumping in unregulated areas poses a major threat to rural residents and plants and animals that rely on shallow groundwater.

Five years ago, California became the last state in the West to regulate groundwater. Many thought this would be impossible until the need for groundwater management became overwhelmingly clear during the last drought.

Let’s not wait for the next drought to finish what we’ve started by learning from these past five years and extending sustainable groundwater management statewide.

Sandi Matsumoto is associate director for the California Water Program at The Nature Conservancy,  [email protected]. She wrote this commentary for CalMatters.

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