Kern River Intertie to SWP Activated to Relieve Tulare Lake Flooding
Intertie Activation, Kern River Watershed System, Tulare Flood Damage, California Water Politics
Press release excerpt from DWR on May 22, 2023:
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.
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.
How decisions were made to open the Intertie gates
The Kern River intertie near the end of the river flow is a connection to the SWP’s California Aqueduct. It was built in 1977, but has only been used 10 times, most recently in 2006. That was to move water from Lake Isabella due to instability concerns of the dam, now repaired. The intertie infrastructure is located west of Bakersfield in the southern portion of San Juaquin Valley. See below:
On May 10, the Kern River Watermaster, Mark Mulkay, requested that the state authorize use of the intertie to divert water flood water from Tulare Lake. The decision to activate the intertie was delayed 10 days as several state government agencies debated about protocol, water rights and a possible need for permits. Following a 2022 SWRCB determination denying the request to reconsider a 2010 unsuccessful petition of 6 water districts that all Kern River water is fully allocated as part of their water rights, without intermittent unallocated excess water, Gov. Newson issued an executive order exempting the move of water by the intertie from permits as well. Water began to flow into the SWP on May 20th, which then “owns” the water.
Kern River Basin and Water Management
The Kern River is one of four rivers and several creeks that continue to flood the Tulare Lake Basin. Spring snowmelt has swollen the Kern River, pushing massive amounts of water into the previously dry lake bottom turned into rich farmland. Approximately 165 miles long, the Kern River is the most southern of the rivers in the San Joaquin Valley. The river cascades down from the Sierra Nevada near the base of Mount Whitney. Its main fork joins its major tributary, the South Fork, near Isabella Reservoir. From Isabella Reservoir to just before Bakersfield, the river drops over 2,000 feet in elevation through the Kern River Canyon. So much water is diverted in Kern County canals to supply farmlands that the river seldom reaches beyond the northeast side of Bakersfield.
The Kern County Water Agency (Agency) is the second largest contractor in the State Water Project. The Agency has long-term contracts with 13 local water districts, called Member Units, and Improvement District No. 4 for SWP water. District No. 4 was formed in 1971 to provide a supplemental water supply for the urban Bakersfield area via importation of water from the State Water Project. The Cross Valley Canal was constructed in 1975 to move SWP water from the California Aqueduct to Bakersfield.
With an average of less than six inches of rainfall per year, Kern County is a semi-arid region. Surface water supplies are not enough to meet the needs of citizens, businesses and farms in the area, so groundwater plays an integral part in how water is managed in Kern County. The Agency works to improve groundwater levels and to monitor groundwater quality throughout Kern County, especially in the areas surrounding groundwater banking projects.
Kern County is one of the world’s most innovative groundwater banking operations. Between 1977 and 2005, Kern County invested more than $300 million to build its groundwater banking infrastructure throughout the county. The water banks can store an enormous 5.7 MAF during wet years, and extract water through pumping during dry years. The City of Bakersfield’s 2800 Acres Spreading Area was the first full-fledged banking project. In the 1990s, banking programs were expanded with the construction of the Kern Water Bank, which encompasses 20,000 acres of recharge ponds and habitat/wildlife land, and the Agency’s 2,233-acre Pioneer Banking Project, which was created for groundwater recharge and recovery operations.
Approximately 800 production wells and 200 monitoring wells measure groundwater levels on a semiannual basis within the Kern sub-basin of the San Joaquin Valley groundwater basin. Groundwater banking is so important to Kern County that nearly all groundwater districts have banking projects within their district’s boundaries.
The Kern River Watermaster acts as the liaison with the Army Corps of Engineers, which operates water releases from Isabella Lake. The Watermaster also keeps track of all the rights and contracts that govern the river and checks on record keeping.
High levels of water along the Kern River this year led to the diversion of water from the river into ponds just west of Bakersfield in the southern part of Tulare Basin. Flooding these recharge ponds allows water to seep into aquifers for long-term storage. Excess water eventually empties into Tulare Lake.
Flood control projects include the Kern River-California Aqueduct Intertie, connecting the two bodies of water. Sponsored by the Agency and built by the U.S. Army Corps of Engineers in 1977, its purpose is to convey Kern River flood water into the Aqueduct to avoid damages to lands downstream of the Intertie. The Agency acts as the superintendent of the project and works in cooperation with the California Department of Water Resources, the Army Corps and the Kern River Watermaster, along with several water districts which receive benefits from reduced flooding in Buena Vista Lake and Tulare Lake.
Kern County is the second largest SWP contractor behind Metropolitan Water District. They are the top two recipients of Article 21 Water this year, described in my recent article about Lade Mead and the Colorado River Basin. This is possible because both have massive water storage capabilities and banked water for later use and sale. As I wrote before, there is no real water shortage!
Flood Damage in Tulare Lake
Tulare Lake was once home to thousands of migratory birds, numerous land and water species and provided for a population of up to 70,000 Native American Yokut people. Between 1850 and 1900, Tulare Lake was known to have varied in size between wet and dry years. At times it was a dry lake bed and other years it swelled to an area of nearly 800 square miles. The lake is the terminal point for 4 primary rivers in the watershed basin; the Kings, Kaweah, Kern, and Tule Rivers.
The Kern River is the southern-most river of the four major rivers. It has the largest drainage basin area and carries the second largest basin runoff. Upriver, Isabella Dam is in a valley at the junction of the mainstream and South Fork branches of the river. After flowing through a deep canyon, it emerges northeast of Bakersfield. From there, the river flows about 12 more miles distributing water into smaller diversions and channeled into canals. The river also receives water from the Friant-Kern Canal from excess flow in the other more northern rivers.
High Kern River flow not used for groundwater recharge empties into either the Buena Vista Lakebed, into the Kern River Intertie and the California Aqueduct, or north towards Tulare Lake via the Kern River flood canals. The Kern County Agency has 34 groundwater recharge sites. The California Aqueduct also supplies water for groundwater recharge through the Kern Water Bank Canal and the Cross Valley Canal. Those two canals can also reverse flow to send water back to the Aqueduct. In flood years, the excess water in the Kern River comes from both runoff and the Friant-Kern Canal. Since the intertie was built, it has handled excess flood water 10 times between 1977 and 2006.
By the early 1900s, Tulare Lake had been essentially engineered out of existence. Today, any water that flows to the area is used to irrigate thousands of acres of cotton, safflower, pistachios and tomatoes that are grown year-round in the lakebed.
The lake has only flooded and reappeared a handful of times since it disappeared, most recently in 1997. In those instances, the water has not only covered agricultural fields, but has at times breached levees and bested other flood prevention infrastructure to flood nearby communities including Corcoran, Allensworth and Alpaugh.
Tulare Lake is a closed basin…it has no outlet. Very little water will sink because of its compact clay bottom. Evaporation is the main way the lake will dry up, which can take two or more years.
Tulare Lake, which has grown to at least 186 square miles near the end of May is still expanding. The water in the lakebed has caused billions of dollars in economic losses and displaced thousands of farmers and residents in agricultural communities. Continued flooding also threatens levees, dams and other ailing flood infrastructure in the area. The nearby town of Corcoran has a protective dirt levee at risk of breaching from rising waters and received emergency federal funding to raise the levee by four feet.
Gov. Newsom’s office has estimated more than $60 million in agricultural losses and still calculating crop and dairy damages. More than 600 structures in Tulare County have been damaged by flooding. More than half of California’s farmworkers, about 200,000, live in the Central Valley. Thousands are losing work, wages and homes. Getting financial and housing help to farm laborers is challenging.
Several towns and rural communities of color also are struggling. In a local conflict that made national headlines, the historic Black town of Allensworth, nearby Alpaugh, and farmers along the Tulare Lake bed were flooded after a large landowner refused to allow his property to flood. As Allensworth residents pleaded for official intervention and scrambled to save their community, SJV Water, a nonprofit newsroom, reported that the landowner had placed heavy farming equipment in the way of a water manager’s efforts to use the farmer’s private canal
Tulare Basin flooding has wreaked havoc on the large dairy industry. Dairies employ more undocumented workers than other agricultural industries, which hire workers from a federal visa program for seasonal workers. Dairies operate year-round. The trade association Western United Dairies estimates $20 billion of damage to the sector. More than 100,000 cows and 15 dairies had to be relocated as farms and milking facilities began flooding in March. Many animals today were on farms completely surrounded by water. The Governor’s Office of Emergency Services has been providing high-water vehicles to get milkers to cows.
Cotton production and the region’s dominant tomatoes crops will be limited. Processing tomatoes were already in short supply after the three-year drought. About 90% of the nation’s processing tomatoes and more than a quarter of the world’s supply come from California. Tomatoes stand to be one of the crops where consumers will see the biggest impact, according to the director of the Kings County Farm Bureau.
In Kings County, where more than 60,000 acres of flooded farmland has been confirmed and 115,000 acres may ultimately be counted, production losses are expected to top $300 million this year. Property damage could be even higher. The county’s annual production has recently been about $2.3 billion.
Closing Thoughts
Although I was quite familiar with the scale and power of Metropolitan Water District, I had not appreciated the massive, complex system of Kern County. Kern County has now likely replenished its groundwater from drought conditions. The Kern County water districts’ petitions to retain rights to ALL the water as totally allocated was denied by the SWRCB, but the attempt is logical in light of the massive infrastructure there.
The Tulare Lake and the basin will take years to recover. Many lives have been disrupted and farming the region will not be possible for at least two to three years, if ever. Another significant blow to food production has occurred, so food prices and availability will be impacted yet again. No mention has been made in the media about efforts to provide assistance to the farm owners, who lost millions of dollars in assets and their homes. Farm workers too are suffering. It’s all a tragic story and another nail in the coffin for the California economy and well-being of its people. I just wonder if the Kern intertie had been activated sooner, could some of the damage been avoided by sending flood waters to recharge dry regions in southern California?