New water rules for California cities aren't enough: Scientists

New urban water restrictions went into effect for cities across California on Monday, but the state will have to do more to prepare for a possible "new normal" of increased demand and dry periods that are longer, more frequent and more intense, a group of scientists said.

California's approach to water management is severely outdated and ill-suited to the state's mostly dry climate, according to Monday comments from members of the Union of Concerned Scientists. The state has to overhaul its water rights system, give its water managers the authority to supervise water use and restrict it when necessary.

But it also needs to begin employing technological solutions: California should focus less on building storage capacity for water, and more on retaining the water from storms and snow, and recycling the water it does use, the group said.

The New Melones Lake reservoir east of Stockton, California.
Mark Ralston | AFP | Getty Images
The New Melones Lake reservoir east of Stockton, California.

California has historically responded to droughts by "slamming on the brakes" once droughts occur and then returning to business as usual when conditions temporarily improve, said Michael Hanemann, a professor at the University of California, Berkeley.

Previous droughts have typically ended after two successive dry winters, Hanemann said. The current drought has lasted three dry winters so far and is continuing, which explains the current panic.

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Meanwhile, longstanding problems remain unsolved, he said. For instance, the state's water rights system is in part based on English laws that have no application in California's dry climate and have been in place for more than a century.

The ongoing political conversation in California marks the second time in the state's history that top leaders are talking about making changes to the system, the first time was during Jerry Brown's first stint as governor in the 1970s, Hanemann said.

A better water-rights system would allow for some kind of market to allow water rights holders to trade or lend their rights to others and would give state agencies the power to gather data on usage, and restrict use where needed, he said.

California's drought drama and how we got here
California's drought drama and how we got here   

But reforming the water-rights system is not the only needed change. The state also needs to think less about building more storage and more about developing strategies for retaining water when it does fall during storms, Joseph McIntyre, president of Ag Innovations, a nonprofit group that works on a range of agricultural issues.

"It is not about building bigger storage, it is about catching and retaining water wherever we can," McIntyre said.

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"Studies are showing that a combination of water recycling and stormwater capture really can make a dent" in meeting water use needs, said Kirsten James, the senior manager of California Policy and Partnerships at non-profit Ceres. She spoke on behalf of the "Connect the Drops" program, a coalition of businesses promoting water recycling and capturing water from sources such as storms.

The group also wants to ensure that legislation regulating the use of groundwater stays "on track," and that wise use is made of a $7.5 billion water bond announced in April.

Juliet Christian-Smith, a climate scientist with the Union of Concerned Scientists, said the state currently lets one million acre-feet of treated wastewater drain into the Pacific Ocean every year, so there is much more that could be done to make use of available water.

California will very likely have to make use of such solutions to prepare for a future where less snow falls in the state, and the new norm includes long droughts interspersed with intense periods of heavy rain and flooding, she said.