South Bay water officials reach deal to greatly expand San Luis Reservoir capacity
After Monday's rainfall in the Bay Area, it may be hard to focus on the fact that climate change is threatening deeper and more frequent droughts. But water managers in the South Bay just entered into a deal that will add a huge amount to their storage by expanding the San Luis Reservoir in Merced County.
Just off Highway 152, between I-5 and the town of Gilroy, the San Luis Reservoir is the fifth largest reservoir in California, and it is completely man-made. The chances that it could be built today are highly unlikely, but the fact that it already exists presents a tremendous opportunity for extra water storage for the southern Bay Area.
But in 1962 it was just a dry valley surrounded by rolling hills. That's when a young, ambitious President John F. Kennedy arrived to show what it takes to move a rapidly growing nation into the future.
"We're going to have 300 million people in another 40 years in this country. A lot of them are going to live in California," Kennedy told a crowd of people at the site. "In many ways, the growth problems and the conservation problems of California are the same kind of problems that our country faces. It is a pleasure for me to come out here and help blow up this valley in the cause of progress," he said, as the crowd laughed.
With that, he pushed a plunger, setting off dynamite in an explosive groundbreaking for the construction of the 382-foot dam that would create the San Luis Reservoir. That's how they did things back then. And ever since, the water supply that was created has benefited water users from the South Bay to the Central Valley. But Kennedy's predictions about population growth were right, and now the demand for water is once again a challenge for the state.
"We need to be drought resilient. We need to adapt to climate change. We need to have water as these drier times move forward," said Aaron Baker, Chief Operating Officer for Santa Clara Valley Water.
He said they have entered into an agreement with seven other agencies to pay nearly a billion dollars to raise the level of the reservoir's dam 10 feet. That may not sound like much, but with the size of San Luis, it will equate to 130,000 acre-feet, enough for about 260,000 households per year. Of that, nearly half —60,000 acre feet — will go to Valley Water.
"Sixty-thousand acre-feet is quite a bit of water," Baker said. "If we wanted to put it into Anderson Reservoir, currently our local reservoir is about 90,000 acre-feet. This will be 2/3 of Anderson Reservoir."
Because Santa Clara Valley Water will receive the bulk of the water storage, they will pay the largest cost, about $430 million. The eight participating water agencies planned to meet with federal officials in Washington D.C. Wednesday to commemorate the agreement they have reached. But it's only happening because of what they did back in 1962.
"This is an existing reservoir," said Baker. "All the plumbing is already there. Valley Water already receives deliveries from this reservoir, and many others receive deliveries from this reservoir. So, the amount of infrastructure related to those type of things is really just a raise of a dam."
For that reason, the San Luis project hasn't faced the same roadblocks from environmental groups that others have. And with the dam currently undergoing federal seismic safety construction, the dam raising can be coordinated with that activity. But it won't be a quick fix.
"It will take some time," Baker warned. "Right now, we've got to make sure that we're working in conjunction with the existing 'Safety of Dams' project. And so that construction is estimated right now to be done around 2032."
The dam-raising project, like the reservoir itself, is a forward-looking idea —with an understanding that it is the vision of people from the past that people in the present rely on every day.