Report: Delta in need of water; too much being diverted to reverse lengthy decline
By Alex Breitler
July 22, 2010
Stockton Record Staff Writer
Delta advocates have long asked how much water the estuary needs to recover from a decades-long decline.
They got their answer Wednesday.
In a new report, state officials estimate that about 75 percent of the Delta's water would need to stay in its rivers and streams and flow out to San Francisco Bay to restore the estuary and recover native fish.
Right now, about 50 percent of the water flows to the Bay. In other words, cities and farms have been taking about twice as much water as the Delta can give.
The report is for information only; it does not require cutting back on water pumping nor does it impose any new rules.
It does, however, contain what officials believe to be the best science so far, and could shape discussions in coming months about a peripheral canal or tunnel.
"This is an ongoing legal requirement ... that cannot simply be shelved," said Cynthia Koehler of the Environmental Defense Fund. "Future decisions about the Delta must be informed by this."
Water users said that the impact on their supplies would be devastating if these higher flows were ever put in place.
The report focuses only on what the Delta environment needs. It does not take into consideration other factors - water rights, for example, and the need to protect human health and safety.
"The (report) is a purely theoretical exercise with no application in the real world," said Dan Nelson, executive director of the San Luis & Delta Mendota Water Authority in Los Banos. The authority provides Delta water to farms on the west side of the San Joaquin Valley.
"Any attempt to apply these findings would be devastating, not only to the people of Southern California but to all of the water users north of the Delta as well," Nelson said in a statement.
On average, 29 million acre-feet of snowmelt and rain flows into the Delta watershed, which encompasses much of Northern California. That's enough water to fill the state's largest reservoir, Lake Shasta, six times.
But only about half of that water actually drains into San Francisco Bay.
Achieving the 75 percent goal "would require a significant amount of water," said Victoria Whitney, deputy director of the State Water Resources Control Board, which wrote the report under orders from the state Legislature as part of last November's package of water bills.
The higher flows could lead to a 30-percent hit for those who export water directly from the Delta, and a 70-percent hit for those who take water upstream, according to modeling by the board. Most of San Joaquin County falls into one of those categories.
Some of that water could be recovered through conservation or water recycling, and by addressing other problems in the Delta like contamination from farms and cities.
Environmentalists praised the report for its focus on flow. Baby salmon need the water to get flushed from the upstream tributaries where they're born; adult fish need the water to climb from the ocean to the headwaters where they can spawn.
It's not often that Stockton environmentalist Bill Jennings lauds the state board, but he did so Wednesday, calling the report an "honest and sincere effort."
"Fundamentally, they're saying this estuary needs more water," he said. "It's not surprising. It's consistent with the last 30 years of scientific testimony.
"Now we know what it takes to protect the Delta."
Contact reporter Alex Breitler at (209) 546-8295 or email@example.com. Visit his blog at recordnet.com/breitlerblog.