Water resources: UC tackles supply and quality

So-called water wars have punctuated California's history, pitting conservationists against developers, residential water consumers against farmers, cities against rural communities and Northern Californians against Southern.

Questions over how much water is available, who should have access to it and how best to distribute it continue to flow through public policy discussions. Increasingly, Californians are questioning the quality of their water resources and the impacts of global warming on supply.

UC researchers have been tackling water issues from a wide range of disciplines. Engineers, hydrologists, economists, environmentalists and more are addressing the challenges of California's aging distribution infrastructure, increasing demand from a growing population and need for more sophisticated conservation measures. Working with state and local water resource agencies, UC researchers bring science and technology to the water policy discussion. Here is just a sample of their research.

Water equity underscores policy decisions

Helen Ingram, professor Department of Planning, Policy, and Design and Department of Political Science, UC Irvine, Drew, Chace and Erin Warmington Chair in Social Ecology
www.uwrc.uci.edu

Social ecologist Helen Ingram specializes in water equity. From her perspective, the underlying issue of fairness moves all water policy debate far beyond just engineering and environmental concerns.

"Water is a symbol of community and humanity," says Ingram, who is affiliated with UC Irvine's Urban Water Research Center. "We believe everyone should have access to a clean, affordable water supply. I think that's built into every single decision we make about water supply."

Ingram is an editor, along with John Whiteley of UC Irvine and Richard Warren Perry of San Jose State University, of a new book titled Water, Place and Equity to be released by MIT Press in October. The book's contributors examine the premise that while Earth may contain sufficient water, the supply is misallocated, wasted and polluted.

The researchers present case studies that examine disparities in distribution and cost on a global and statewide level. With the effects of climate change on water supply, these researchers see a growing water crisis that in the future will dominate resource politics in the same way oil does today.

In California there are ongoing equity questions about transferring water out of rural agricultural communities, maintaining the ecological health of waterways and building new housing when there is limited water supply. The slump in the housing market won't necessarily solve the equity issue, Ingram says, because often when the housing construction industry declines, builders just look for cheaper land farther from urban hubs.

"We can't depend on the economy to slow down growth," she says.

The true cost of water is artificially low, Ingram says, and the price of water, connection fees and building permits should start reflecting the reality of water supply.

In addition, California's budget shortfall shouldn't be allowed to derail efforts under way to address the environmental crisis in the Sacramento-San Joaquin Delta, she says. The same goes for proposals to address the state's aging water storage and distribution infrastructure. The water bond measure being pushed for the November ballot needs to be scrutinized in terms of fairness to all the affected stakeholders, said Ingram: "We can't take a vacation from water."

Snowpack research measures up

Roger Bales, professor, School of Engineering, UC Merced, acting director, Sierra Nevada Research Institute
snri.ucmerced.edu

Critical to sound water resource management is knowing how much water is out there. In the Sierra Nevada, source of much of California's water, UC researchers are developing new technologies to accurately forecast water supply.

"In terms of resource management, we're bringing new technology into mountain hydrology," says Roger Bales, acting director of the Sierra Nevada Research Institute, headquartered at UC Merced. "We're providing the knowledge and tools to modernize our information system in the Sierra Nevada."

The traditional methods used to measure the mountain snowpack were developed decades ago, says Bales, and the forecasts were made using historical data.

"These were good, but not in very dry years or when we start getting very wet years," he says.

Even a 10 percent error in forecasting can have costly consequences for California farmers and water agencies. Farmers base their crop plantings on how much water will be available. Overplanting or underplanting can seriously affect their bottom line. To prevent flooding, water managers need to know how much water they can expect from snowmelt runoff and when to expect it.

The new generation of water measurement technology Bales works with uses a combination of satellite imaging and ground-based, low-cost sensor networks. Daily images from satellites tell researchers what mountain areas are covered in snow.

Researchers have deployed clusters of ground sensors that collect data about snowpack depth, density, moisture content and temperature. This gives a more accurate measurement than the traditional method of sinking a hollow pole into the snow to measure depth and retrieve a core sample.

Researchers track groundwater dairy pollution

Thomas Harter, R.M. Hagan Endowed Chair in Water Management Policy, UC Davis, Cooperative Extension groundwater hydrologist
groundwater.ucdavis.edu

UC Davis hydrologist Thomas Harter studies the impact California dairies have on groundwater quality. For the last 10 years he has been working with dairy farms in the San Joaquin Valley to test the level of nitrates, salts and pathogens that travel into groundwater from herds and the waste they produce.

As more rural areas in the state become urbanized and growing populations tap into the groundwater, quality and safety become an even bigger concern. High concentrations of nitrates in drinking water are especially dangerous to infants, resulting in a condition known as "blue baby" when nitrate converts to toxic nitrite in the body and inhibits blood from carrying oxygen.

Using a network of monitoring wells, Harter has found high concentrations of nitrates and salts in the sandy soils of the Northern San Joaquin Valley where groundwater is found at shallow depths of 10 feet below the surface. Last summer Harter's research group extended the reach of the monitoring studies by drilling wells on dairy farms in Tulare and Kings counties where soil is denser and groundwater collects at deeper levels.

If high levels of contaminants are discovered, Harter helps farmers develop management plans to mitigate the problem. Having accurate data about the nitrate levels of fertilizer helps farmers know exactly how much – or little – to spread on their fields, and that prevents over-fertilizing.

"None of my work is isolated from the community that uses it," Harter says. "We're making sure the best possible science is available to them."

Contaminants leach into the soil through both the solid and liquid manure farmers spread on their fields to fertilize forage crops for the cattle. Each phase of dairy production can create a different source of contamination. Harter monitors the production area where herds are housed, the lagoons where manure is separated and stored, and the fields that are fertilized.

Nitrate has many different sources: dairy lagoons, manure applications, crop fertilizer, septic systems, urban wastewater, golf courses and even rainfall. Using technology developed at the U.S. Geological Survey and Lawrence Livermore National Laboratory, Harter and his colleagues are working on methods to identify the source of the groundwater nitrates through their isotopic signature or other "fingerprints." That gives valuable information to farmers, planners, regulators and citizens about where contamination occurs.

"Everyone likes to point the finger at everyone else," Harter says. "This work helps us understand where the nitrate is coming from."

Knowing the source of contamination allows farmers and public agencies to concentrate their management efforts and costs in the areas that need it.