There have been drought years in the past that have not drawn the lake down as low as it is now. There are those that estimate that San Luis Reservoir will reach its all time lowest level in history by this August at the current rate this year. What has changed since we are not as far into a drought as in previous years? The primary reason for the San Luis drawdown is keeping enough water in the Sacramento River to preserve endangered species. I am all for that, but it is interesting to note that we have reached a point now in Fisheries management when we must choose between the lesser of evils–one conservation plan over another. Im reading Dan Browns latest novel–Inferno–which is a fiction about one scientist’s mad plan to lower the population of the world in order to save it. Im afraid that the needs of the many are beginning to become more important than the needs of fish, despite science screaming at us that there is a fine line between preserving our resources and the survival of our species.
By Mark Grossi — The Fresno Bee
Massive San Luis Reservoir will turn into a mud puddle this August on the San Joaquin Valley’s west side — maybe a historic low.
The mud puddle will be a symbol of frustration in the nation’s biggest farm water district, Westlands Water District, which depends on this unique California reservoir. For 1.8 million Santa Clara County residents who get water from here, the shortage threatens both water quality and supply.
The rest of the state copes with drier-than-usual conditions after two dry winters. But San Luis has been hit with an extreme water shortage, mostly because it is so different from other large reservoirs in California.
Its only source of water is the troubled Sacramento-San Joaquin River Delta, where water pumping was restricted in winter to protect dying fish. There was a lot less water sent to San Luis this year.
The 2 million acre-foot San Luis Reservoir last week was down to 620,000 acre-feet, about 40% of average for mid-June. Each 326,000-gallon acre-foot is becoming more precious every day.
“San Luis has been dropping like a rock since April,” said Westlands general manager Tom Birmingham.
Located in the dry, grassy hills west of Los Banos, San Luis is the country’s largest reservoir without a natural stream to feed it. River water from the delta is sent about 70 miles through canals to form this artificial lake used by both the federal and state water projects.
For motorists on Highway 152, the route between the San Joaquin Valley and the coast, it is a major landmark, including the reservoir on one side of the roadway and O’Neill Forebay on the other. The forebay collects incoming water from the delta, and pumps lift the water into the main reservoir.
President John F. Kennedy attended the San Luis Dam groundbreaking in August 1962, joining Gov. Pat Brown in pushing plungers to trigger explosions that started construction.
Kennedy famously said, “It is a pleasure for me to come out here and help blow up this valley in the cause of progress.”
The reservoir had long been considered a chance to slow west Valley agriculture’s chronic overdrafting of the underground water, which continues today and increases in dry years, such as this one.
But farm water leaders say this year’s problem is more than a dry winter. They calculate nearly 1 million acre-feet of water — about enough to fill Millerton Lake twice — were lost as a result of delta pumping curtailments under a federal plan to protect threatened delta smelt.
“We’re not even close to having the driest year on record,” said Birmingham. “But the reservoir might be at a record low in August.”
Projections show the reservoir’s pool of water probably will bottom out at about 150,000 acre-feet.
That’s below any past year, except when the reservoir was drawn down for maintenance in the 1980s.
It would be lower than the 188,000 acre-foot low point of 1989, which happened in the first few years of an extended drought.
Drawing down San Luis is actually the goal each year. It’s the most efficient way of using the reservoir, according to the San Luis & Delta-Mendota Water Authority, representing 29 federal water customers on 2.1 million acres of land, including Westlands.
But the reservoir should be full in spring, and that didn’t happen this year, the agency says.
“San Luis Reservoir should be full in April and May and empty by August or September,” said executive director Dan Nelson. “We’re clearly very short this year.”
Farmers in the 600,000-acre Westlands and other districts buying federal water to farm the westside can expect only 20% of their contracted allotment.
Districts are scrambling to buy water from other sources, such as water districts in Northern California, but extra water is scarce this year.
Some farmers have allowed some crops to dry up, so they can be sure their more lucrative orchards survive. Others are drilling deeper wells.
The low point in San Luis could hit just as hard for Santa Clara Valley, another Central Valley Project customer getting water from San Luis. Intense algae blooms are known to spread in the reservoir as the level drops and the Central Valley’s temperature rises.
The algae can be expensive to filter for drinking water, and it can clog drip irrigation systems.
The U.S. Bureau of Reclamation, which runs the Central Valley Project, is hoping cooler temperatures will reduce the algae blooms.
But the Valley is known for 100-degree-plus days in July and August.
“It could be a very difficult summer,” said Elizabeth Kiteck, chief of the bureau’s water operations division in the Central Valley.
When the reservoir drops to 300,000 acre-feet, deliveries to the San Felipe Division of the project — which includes Santa Clara Valley — could be interrupted because of the algae problem, the bureau said.
As city water users, Santa Clara Valley will get 70% of its contracted allotment. People get a higher priority than crops. But that still leaves the district short.
Marty Gomes, spokesman for the Santa Clara Valley Water District, said the agency this year will retrieve up to 40,000 acre-feet of water that it has stored in an underground water bank in Kern County.
“We have planned for dry years,” he said. “But the federal water from San Luis Reservoir is a significant portion of our supply.”
Read more here: http://www.fresnobee.com/2013/06/15/3345553/mud-puddle-on-the-west-side.html#storylink=cpy
