The California Department of Water Resources (DWR) is using a unique piece of State Water Project (SWP) infrastructure for the first time since 2006 to reduce the amount of flood waters going into Tulare Lake in the Central Valley.
At the request of the Kern River Watermaster, the Kern River Intertie is now redirecting flood flows at a rate of 500 cubic feet per second (cfs) from the Kern River to the California Aqueduct to lower flood risk in Tulare Lake and for downstream communities in Tulare County. The Intertie is located west of Bakersfield near where Highway 119 crosses the Aqueduct.
While there is no immediate flooding or public safety concerns, timely use of the Intertie is critical to help prevent additional floodwater from exacerbating flooding in Tulare Lake as river flows increase.
Water flows entering the California Aqueduct will stay at 500 cfs and may increase to 1,000 cfs later this month. The Intertie is capable of handling up to 3,500 cfs of maximum flood inflows, however the expected operations will be between 500 and 1,500 cfs.
If the Intertie flows remain at approximately 1,000 cfs until the end of June, it is estimated that about 75,000 acre-feet of water will be redirected from the Kern River to the Aqueduct, keeping that water out of Tulare Lake.
The Intertie’s operations will be monitored, adjusted, and terminated by DWR in coordination with and at the request of the Kern River Watermaster.
Once the water that is being redirected enters the Aqueduct, it is considered State Water Project water. The flood water is not additional water for the system but rather is part of the 100 percent allocation that DWR announced in April. The Kern River flood water will offset water that would have otherwise been exported from the Delta or drawn down from San Luis Reservoir.
DWR continues to monitor water quality levels in the California Aqueduct and provides test results to State Water Contractors receiving SWP water.
During historically wet years, flood water from the Kern River has been redirected into the Aqueduct. The Intertie was last used in 2006.
This year marks the 10th time that the Intertie has been used since it was built in 1977. Of all the uses, the 755,514 acre-feet of water in 1983 was the largest amount of water entering the California Aqueduct from the Intertie.
The Kern River Intertie’s main purpose is for the benefit of redirecting flood waters and protecting downstream communities.