Friant Dam 101
After experience more rain here in Fresno and in California than we’ve seen in recent years, how will that affect water storage? GV Wire went up to Friant Dam, just north of Fresno to find out.
Melting snow and rain help fill Millerton Lake, formed by the building of the dam in 1942. That water flows through the dam, supplying the water for the San Joaquin River. The river flows down towards Mendota, then north into the Sacramento Delta.
Millerton Lake holds 520,500 acre feet of water. Right now, the lake is at 70% capacity. Duane Stroup, Deputy Area Manager for the U.S. Bureau of Reclamation, the federal agency that manages the dam, says that is higher than normal. He says that is a little higher than normal for this time of year. They want to leave room for unexpected storm water. During the dry years, Millerton can go as low as 29%.
“We like it when it rains to be nice and cold so it falls as snow. That is our main form of storage. Then that stores the water. As that melts, it flows into our reservoir and reservoirs up stream. We want it to melt at just the rate where we can store it and send it south and north for beneficial use,” Stroup commented.
About 4,000 cubic feet per second (CFS) are being released through dam, which fills the San Joaquin River as well as the Friant-Kern Canal and the Madera Canal. That amount is approximately 8,000 acre feet a day. One acre-foot is equal to 325,7851 liquid gallons. During the summer months, only about a tenth of the water released now would be let out.
The water is used for agriculture on the eastside of Fresno County as well as municipal use by customers like the City of Fresno. The dam also helps flood control, especially during the rains. “What we want to do is regulate flow so we don’t flood people out that are downstream,” Stroup says.
Westside farmers, meanwhile, receive their water pumped in from the Delta. “The main reason why they don’t get it from (the Friant Dam), is because the water supply is not as dependable as it is in the Delta,” Stroup explains. “We put the pumps where they have a greater chance to be used every year.” He says that flows from Friant haven’t been like this for five years.
Some of the water that makes it to the Delta will flow out to the ocean. More storage, such as the proposed Temperance Flat Dam could help keep the water for ag use. “As long as the storage was on the San Joaquin River, yes. If there was more storage, we can store more water and less would flow to the ocean,” according to Stroup.
Another big issue is the drought. “It’s much better to be in the situation we are in now than the last few years. It has been really tough to operate. We have had to release water to meet other demands and gave zero allocations and no one is getting any water out of this reservoir,” says Stroup.
How does Stroup respond to whether these winter storms have ended the drought? “Nobody knows. We are looking at a good year this year. The only time you know when you are out of the right is when you look back and say you are out of the drought. It is looking like a nice wet year.”