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A yard on the left has let their grass go dry, while a house next door has green grass in the Cambrian neighborhood located in West San Jose on July 21, 2021. Water restrictions are in place in San Jose which restrict the length of watering and limits the timing. Beth LaBerge/KQED
A yard on the left has let their grass go dry, while a house next door has green grass in the Cambrian neighborhood located in West San Jose on July 21, 2021. Water restrictions are in place in San Jose which restrict the length of watering and limits the timing. (Beth LaBerge/KQED)

San Jose Relies On Water From the Sierra Nevada. Climate Change Is Challenging That System

San Jose Relies On Water From the Sierra Nevada. Climate Change Is Challenging That System

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In Santa Clara County, lawns are dry, a reservoir is nearly empty, and water restrictions are mandated. After two winters with very little rain — and San Jose’s driest year in 128 years of record keeping — the county is marked by one of the worst droughts in modern history.

Santa Clara County’s experience of drought is set apart from the rest of the state by a myriad of issues — less water from the Sierra Nevada, the effect of human-caused climate change on water supplies, and a case of incredibly bad luck.

“This is a dire emergency caused by the confluence of several horrible things happening all at the same time,” said Gary Kremen, director of Santa Clara Valley Water. “This isn’t like someone crying wolf.”

Valley Water relies heavily on water from the Sierra Nevada snowpack more than 100 miles away. But the agency only received 5% of the water it contracts from the state this year, a quarter of what it sources from the feds, and very little local rainfall.

“We have 2 million people in the county, compared to San Francisco’s 800,000 or Oakland’s 500,000,” he noted. “This is where the people live. We use a lot of water.”


Kremen likens the drought situation in his water district to someone losing their job without savings to fall back on and no outside help to get them through.

“You got no money coming in and none of your relatives want to send you any money because they have their own difficulties,” he said.

Santa Clara County is so dry and the water levels so low, that Kremen’s agency now requires a 15% reduction in water use from all people and businesses. That amount may not not sound like a lot, but if it doesn’t rain this winter, places like San Jose could be in deep trouble next spring or summer.

“I do not believe there’s enough water for a third year [of drought],” Kremen said. “It’s gotten horrible very quick.”

Anderson Lake is 3% full after it was drained so the dam could undergo a seismic retrofit. (Ezra David Romero/KQED)

The Kicker

The kicker on top of two very dry years in a row? The largest reservoir in Valley Water’s system is virtually empty at 3% full, after it was emptied so that the Anderson Dam near Morgan Hill could undergo seismic retrofitting.

“When it’s full this is our primary water supply in addition to our aquifer,” said John Varela , a director on the Santa Clara Valley Water District Board of Directors. “But it’s empty, and we’re in a drought, so it’s not a good time.”

The agency drained the reservoir because the dam is vulnerable to shaking from a severe earthquake. The state wanted to make sure it could withstand at least a magnitude 7.0 quake, and the federal government mandated the retrofit. The work won’t be finished for about a decade.

A Fundamentally Different Climate

In the meantime, Varela says the water district is exploring one possible solution for future water shortages: recycling wastewater. That clean water would then go back into the earth, restoring aquifers.

“We feel that recycled water is the sustainable water supply of the future,” he said.

The agency currently recycles 5% of its water at a facility in San Jose. Varela says the district is partnering with Palo Alto and Mountain View to build a second facility, and with Morgan Hill and Gilroy for a third.  He said preliminary conversations are taking place around creating pipelines throughout the county to share water.

The district would like to double the amount of recycled water in the coming years. But warming temperatures are threatening the very system that supplies water to San Jose, and recycling efforts and other measures might not be enough.

“We now live in a fundamentally different climate,” said climate scientist Katerina Gonzales, who studies the causes and impacts of extreme precipitation at the University of Minnesota. She recently finished her dissertation at Stanford, where she focused on the West.

Tall, dry grass grows across from a green yard in the Cambrian neighborhood located in West San Jose on July 21, 2021. (Beth LaBerge/KQED).

She says warming has condensed the rainy season and is decreasing the annual snowpack. Both are challenging California’s aging water system, which was designed to gradually collect runoff from snowmelt. Not to capture a winter’s worth of rainfall during a couple big, wet storms, known as atmospheric rivers.

“Changes in atmospheric rivers affect almost every part of our infrastructure that deals with our relationship to water,” she said.

If storms come too early in the rain season, reservoirs fill up, creating a flooding risk. If water managers release water too soon in a drought year, it could mean dry reservoirs down the line.

“We can’t rely on this assurance of drought busting atmospheric rivers because of the way that the ingredients in the atmosphere have changed,” Gonzales said.

If California’s water system doesn’t evolve to mitigate impacts from climate change, Gonzales says places like San Jose will continue to have water issues.

State water officials seem to agree that the system has to change. Karla Nemeth, director of the California Department of Water Resources, says the state’s water system needs a major overhaul and Californians will need to save more water.

“We’re still working off past hydrology that was feeding a state that had fewer people,” she said. “All that needs to change, and it can change, if we get focused on how we adapt all of our modeling and operations to accommodate more climate extremes.”

Adam Whyte, 18, spreads mulch around his front yard. The family lawn died in the last drought. (Ezra David Romero/KQED)

What Drought Means For Residents

For residents in the San Jose region, these water woes translate to mandatory 15% water restrictions. People are cutting back mostly on irrigation, like watering lawns, gardens and parks. Even though people are letting their lawns go, water leaders say that can be avoided.

“Your lawn is still going to be nice, it just takes a little bit more time to be judicious about it, reprogramming your irrigation control to the right duration,” said John Tang, vice president of regulatory affairs for San Jose Water. 

Tang says people have learned to save water since the last drought in San Jose. Statewide, Californians use 16% less water.

“There’s certain homes around here that have really heeded the call for conservation,” he said. “People are ripping out lawns and putting in drought tolerant landscaping.”

He says the 15% water reduction is mandatory, but the city is focusing on education and not enforcement. During the last drought, reduction grew to 30%.

“We don’t have any water cops driving around giving people tickets,” he said. “We see it as more of a cooperative partnership.”

In San Jose, brown lawns and drought-tolerant yards are becoming commonplace.

Eighteen-year-old Adam Whyte’s family allowed their lawn to die during the last drought. “It was an eyesore compared to everybody else in the neighborhood who had all this perfectly nice grass,” he said.

This year, his family is mulching the yard with bark from a neighbor. The high school senior is spending part of his summer break with a shovel in hand.


“We’re just gonna spread it out, put up some bricks, maybe a little border,” he said. “Clearly, if we want grass that’s just gonna up the water bill. We’re not doing that.”

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