In what is believed to be a first, the California Department of Water Resources and U.S. Bureau of Reclamation are asking the state board that oversees water rights to investigate water diversion practices by farmers in the Sacramento-San Joaquin Delta. The two powerful water agencies say they suspect farmers are taking water released from upstream dams and intended for consumers in other regions of the state.
The California Sportfishing Protection Alliance, a group often allied with Delta landowners, has countered by filing a formal complaint against DWR and Reclamation, alleging that those agencies are illegally diverting water from four major rivers that flow into the Delta.
The Delta, a complex tidal estuary, has long been a source of water conflict in California. But the brewing battle – with the two sides now openly challenging each other’s water diversions – reflects the heightened tensions over water supply as California weathers a third year of drought.
The estuary collects half of all the freshwater runoff in California. Historically, this fresh water mixed with salty water from San Francisco Bay to nourish a rich inland estuary. But over the past century, the estuary has been channeled and developed into a kind of switching hub for California’s complex water delivery network.
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It has always been difficult to sort out the origin and ownership of water passing through the Delta. Because it is an aquatic mixing zone as big as Rhode Island, tracking the provenance of any given water molecule is unreasonable, if not impossible. Diverters operate on the honor system, each taking only what they need for crop irrigation, or only what their water right allows.
The rival claims suggest the honor system is breaking down.
“We recognize that we’re suffering losses of storage, but we don’t have the data to determine precisely where,” said DWR spokeswoman Nancy Vogel. “Based on what we see, it indicates a potential unlawful diversion of stored water.”
In a July 23 letter, DWR and Reclamation ask the State Water Resources Control Board to investigate water rights in the south and central Delta to determine whether landowners are taking water that does not belong to them. The letter specifically asks the board to use new emergency powers granted by drought legislation passed earlier this year. If the board does so, water rights holders would have five days to provide information on their diversions.
Reclamation officials did not respond to a request for comment.
Delta landowners have denied the allegations and submitted several letters to the water board protesting the call for an investigation. The landowners say they view the request as a desperate measure, because many of the issues have been addressed before. As recently as 2012, in response to legislation, the state water board investigated more than 1,000 water rights in the south and central Delta and found just 12 cases that merited enforcement action.
“It’s just so silly that you would think it’s mainly a harassment technique,” said George Hartmann, a lawyer representing property owners on McDonald Island, a 6,000-acre Delta farming tract near Stockton.
Dante Nomellini Sr., a Stockton attorney who represents the Central Delta Water Agency, said DWR and Reclamation have another objective: easing the water shortage for the agricultural and urban agencies that buy water from them.
“The proposed emergency actions are clearly for the purpose of increasing exports from the Delta,” Nomellini wrote in a letter to the state board.
On Wednesday, the California Sportfishing Protection Alliance struck back. The group alleges that DWR and Reclamation are committing a similar offense by illegally diverting water from the San Joaquin, Mokelumne, Cosumnes and Calaveras rivers. DWR and Reclamation have no water rights on these rivers, said alliance executive director Bill Jennings, yet they divert the water from these rivers when they pump from the Delta.
“Basically, the Bureau and DWR opened a Pandora’s box,” said Jennings. “The water board needs to begin to unravel this.”
The California Department of Water Resources and U.S. Bureau of Reclamation operate the state’s largest reservoirs – including Shasta, Oroville and Folsom – which store water for 25 million people and 3 million acres of farmland. Legally, they have rights only to water where their dams are situated: the Sacramento, Feather and American rivers.
The reservoirs collect mountain snowmelt and release it to the Sacramento-San Joaquin Delta. There, two giant pumping systems divert it into canals that ship the water west to Silicon Valley and south as far as San Diego.
The water agencies want to know whether farmers on Delta islands are intercepting that water before it can reach their pumps. They suspect this because they know how much water they are releasing from their dams, Vogel said, and they’re not seeing the same amount of water available later to divert at their Delta pumps.
In addition to serving their customers, DWR and Reclamation are required by state law to release stored water to prevent salinity intrusion in the Delta, which alters water quality in the estuary. They say the effectiveness of these releases also potentially is being compromised.
“We’re not seeing what we would expect in terms of outflow in the Delta, and we want more information,” Vogel said. “Things are so tight this year in the system that we’re trying to preserve stored water to meet water quality standards, for waterfowl sanctuaries, and for municipal supplies for health and safety.”
Farmers on some 70 islands in the Delta have high-priority water rights that predate the dams and canals. These rights entitle them to divert as much water as they need to grow crops – as long as those diversions are limited to the “natural” flow in Delta channels. Known as riparian and pre-1914 water rights, they are only loosely regulated by the state and supersede even the water rights held by DWR and Reclamation.
At issue in the dispute is whether Delta farmers are exceeding their rights by diverting not only natural flows, but also water that DWR and Reclamation had held in their reservoirs for delivery to their urban and agricultural water contractors.
Delta water users are required to regularly report the amount of their diversions, but DWR asserts those reports don’t include enough useful information. For example, diversions within the Delta are generally not measured by flow meters. Instead, farmers have been allowed a more economical approach, in which they estimate diversions based on the water typically consumed by their crops.
Water diversions in the Delta are especially complex because it is a tidal ecosystem. Because it lies at sea level and is connected to the Pacific Ocean, there is always water in the Delta. But the quality varies based on the amount of fresh water moving through, the effect of tides, urban and farm runoff and other factors.
And there is disagreement about what constitutes natural flow. Landowners assert that they are entitled to more than upstream runoff because of the tidal effect, which creates a “pool” of mixed water in the estuary. Although this water may be salty to some degree, it is usually fresh enough to grow crops.
DWR and Reclamation, however, say the claim to “pool” water is not valid because it may include fresh water released by their dams upstream. If this water is diverted to grow crops in the Delta, DWR and Reclamation claim it imposes direct costs on them because they will be forced to release even more water to serve their customers or to maintain water quality in the Delta.
Hartmann, the Delta lawyer, said the concept of pool water is important for another reason. After Delta farmers irrigate their crops, they have to pump the leftover water back into the estuary. Each island has a system of drainage ditches and pumps for this purpose. The interior of most Delta islands is below sea level, and the soils are porous, so Delta water would seep into the islands, even without crop irrigation.
In reality, Hartmann said, farmers end up draining more water into the Delta than they draw out for their crops.
If Delta farmers were required to cut back their water diversions, he said, many could be forced to fallow some land, which would then fill up with weeds and natural vegetation fed by natural water seepage. DWR’s own studies have shown these plants consume more water than farm crops, which could result in a net increase in water usage.
In addition, he said, if farmers are growing fewer crops, they would have less revenue to operate drainage pumps. This means some islands could fill with standing water, which would be subject to evaporation losses.
“The fundamental point is that farming uses less water than doing nothing,” Hartmann said.
Officials at the State Water Resources Control Board have not yet decided how to respond to the competing claims.
“We are still considering next steps,” said spokesman George Kostyrko.