Better data key to informed water policy decisions

By Christine Souza 


To adapt to climate extremes and become more water resilient in California, modernizing the state’s water data—including the way it is collected, stored, shared and used—may lead to more informed decisions.

Improving data practices to best manage California’s water resources helped drive discussions last week as state and local water managers, farmers, environmentalists and others gathered in Sacramento for the 62nd annual California Irrigation Institute Conference.

“To really understand what that vulnerability is from the headwater to the groundwater to the outflow in a watershed, we need to bring together multiple data layers,” said Kamyar Guivetchi, planning division manager for the California Department of Water Resources. “Those same layers will help us come up with adaptation strategies that can help us get in front of and hopefully manage the impacts of climate change.”

With a theme of “Fluid Futures: Adapting to Extremes,” the Feb. 26-27 event focused on leveraging information and data technology to help with water-management decisions.

Erin Urquhart, water resources program manager for the National Aeronautics and Space Administration, offered insights on the benefits of Earth-observing missions that gather water data from space.

“Over the next decade, NASA is leading an outpouring of information from space,” she said. “Many people think of the moon and Mars when they think about NASA. Most people are not aware that we have 34 missions in orbit or in implementation observing our planet, with another seven already in formulation acquisition.”

NASA observations look at precipitation, snow cover, groundwater, surface water, soil moisture and water quality around the globe. “It is a complex place where environmental, geological and geophysical processes are happening at once,” Urquhart said.

“Water use has grown more than two times the rate that the population increased over the last century. By 2025, approximately 1.8 billion people will live in areas plagued by water scarcity,” she said. “Two-thirds of the world population lives in water-stressed regions.”

As water becomes scarcer, information becomes more useful and critical, she said. To help with data collection, on Feb. 8, NASA launched the Plankton Aerosol Cloud, ocean Ecosystem, or PACE, mission to observe oceans, terrestrial ecosystems and atmospheres.

“PACE is really going to help us to identify and track harmful algal blooms in our coastal waters, and our large inland lakes and rivers,” Urquhart said. “It is going to let us look at the land use and land cover impact on downstream water quality, supply and ecosystems.”

She said the Surface Water and Ocean Topography, or SWOT, a satellite system launched in 2022, “is going to give us a digital elevation map of the global waters, so basically the height of water both in surface waters, the ocean and groundwater.”

NASA often works with the water-resource community to help solve regional challenges. Examples include mapping field-scale evapotranspiration and working with Gallo Vineyards to improve water-use efficiency.

Thomas Painter, who led development of the program that would become the NASA Airborne Snow Observatory, shared details on advances related to gathering snowpack data.

“Now that we’re in a changing climate, we’re really going to be suffering without that more advanced knowledge of the water cycle, in particular, the snowpack,” said Painter, lead scientist and founder and CEO of Airborne Snow Observatories Inc.

“The reason that we want to map snow-water equivalent and snow albedo (reflectivity), is those are the two most critical properties of the snowpack that control the magnitude and timing of snowmelt runoff,” he added.

Snow-water equivalent and snow depth, Painter said, are measured by mapping snow depth from scanning LiDAR, or Light Detection and Ranging, a method of remote-sensing technology.

“Our accuracy for snow-water equivalent is about 1% to 2% and that has to be consistent for our users because they need to know—not in July, but now—how much water there is going to be,” Painter said. “Accuracy is paramount. It’s really moving us from a fairly fuzzy understanding to a far more quantitative understanding and that is absolutely where we need to go.”

To advance open water data in California, the Legislature in 2016 passed Assembly Bill 1755, the Open and Transparent Water Data Act, to create a first-of-its-kind water data program.

“AB 1755 is not about a data warehouse; we’re not trying to suck in everybody’s data,” Guivetchi said. “We’re trying to make the data that’s out there discoverable and interoperable by using some common data standards, and that requires communication and engagement.”

As a result of the legislation, the California Water Data Consortium was created. It is working on an open-source groundwater accounting platform, which includes user-scale water budgets and OpenET data on evapotranspiration—the amount of water released from plants, soil and other surfaces.

“We’ve seen agencies, farmers and other water users increasingly seek out highly granular data to reduce uncertainty in decision making and minimize the risk of wasting precious water supplies due to a lack of precise information,” said Alexandra Biering, a California Irrigation Institute board member and senior policy advocate for the California Farm Bureau, which was a sponsor of the conference. “This is especially critical for pivoting quickly on water-management strategies when our climate seemingly boomerangs between drought and floods.”

Tulare Irrigation District general manager Aaron Fukuda said the district has a long history of collecting data but is “evolving to data collection that helps inform what we’re doing.”

“We moved to evapotranspiration measurements and we are doing some effective precipitation calculations to truly know how much demand was being met by surface water and groundwater,” said Fukuda, who also serves as interim general manager of the Mid-Kaweah Groundwater Sustainability Agency. He added the district was an early adopter of SkyTEM, which is aerial electromagnetic survey technology that maps groundwater.

Guivetchi mentioned Gov. Gavin Newsom’s September 2023 executive order on the state’s use of artificial intelligence, technology that enables computers and digital devices to learn, read, write, create and analyze. A related report, Guivetchi said, “will begin laying out guidance for state agencies for how we procure AI software; how we use it and to make sure that we use it in a safe and secure way.”

For a more sustainable water future in California, Guivetchi said water sectors must work together and co-manage at the watershed scale.

“What that means is getting all the disciplines together to plan multibenefit projects, and then knit our pots of money together to actually get those projects implemented,” he said.

(Christine Souza is an assistant editor of Ag Alert. She may be contacted at

Permission for use is granted. However, credit must be made to the California Farm Bureau Federation