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Blog Post · March 15, 2018

California Makes Progress on Water Accounting

California’s water accounting system—the balance sheet of where and when water is available and how it is being used—lacks common standards, suffers from major data gaps, and is in need of modernization. A 2016 law, the Open and Transparent Water Data Act (AB 1755), directed several state agencies to improve this system. The Department of Water Resources (DWR)―in concert with other state agencies, non-governmental organizations, and universities―is taking the charge seriously and has set ambitious objectives to be completed within a tight timeframe.

The law requires California to create a statewide system for organizing and sharing water data by September 2019. Currently, water-related datasets are stored in many ways, including on public websites, on non-public servers, and even in paper filing systems. The proposed system will make it easier to find and use the data needed for water management, consolidating datasets into several agency-level collections and allowing users to search from a centralized search engine―similar to how an inter-library loan system works.

DWR collaborated with several research institutions to develop guidance for implementing AB 1755. The researchers examined how local, state, and federal water managers, businesses, community groups, and environmental organizations currently use water data to make decisions. Their findings highlighted situations where better data organization could lead to more efficient and effective decision making.

“We recommend that the new system be designed to reflect real-world water management decisions, to ensure that the final product is relevant and useful to water managers and other stakeholders,” said Alida Cantor of Portland State University, who led the research on behalf of UC Berkeley’s Center for Law, Energy & the Environment.

Beyond problems of data organization, California also has some major data gaps, including accounting for groundwater use and recharge, managing water for ecosystems, and assessing rural communities’ access to safe drinking water.

While AB 1755 doesn’t require the state to fill these data gaps, the new guidance by research institutions has improved understanding and flagged some specific gaps that hinder management decisions.

For example, information on surface water rights and the location of many groundwater wells is not in easily accessible formats. And streamflow monitoring is unavailable for many important aquatic ecosystems. These three data gaps make it difficult for regulatory agencies to permit water trading between water users and the environment—a way to dedicate water to improve the in-stream environment. A current legislative proposal would have the state take a closer look at where more stream gages are needed.

AB 1755 is a “foundational first step” in the path toward better accounting for California’s water, according to Mike Kiparsky, director of UC Berkeley’s Wheeler Water Institute, who helped develop the new guidance. DWR and its partners will prepare a final strategic plan for the new statewide data system in spring 2018. This may also be an opportune moment to take a closer look at high-priority data gaps and develop concrete plans to address them.

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