Thousands of water rights holders, including farms and municipalities, that draw water from the Sacramento-San Joaquin Delta could lose access to their supplies under new emergency drought measures approved by the State Water Resources Control Board this week.
The Water Board voted unanimously Tuesday for the “emergency curtailment regulation” in order to protect drinking water supplies, prevent sea water from pushing into the Delta and to minimize the drought’s impacts on fish stocks and the environment, according to Water Board officials.
If approved by the state’s Office of Administrative Law, the measures could go into effect by as early as this month and would require roughly 5,700 of the Delta watershed’s 6,600 water rights holders to stop drawing water.
People who hold water rights that were acquired prior to 1914 — the so-called senior water rights holders — and those with riparian water rights — those who own property that physically touches a body of water — would not be required to curtail their supplies under the emergency measure.
Water Board chairman E. Joaquin Esquivel said:
“It is imperative that we move urgently to better manage the water we still have and prepare for the continuation of drought conditions.”
The curtailments are intended to maintain water supplies primarily in three key upstream reservoirs — Shasta, Folsom and Oroville — that are well below historical averages for this time of year.
As of July 25, Shasta was at 32 percent of capacity, which is 45 percent of its historical average, while both Folsom and Oroville were at 25 percent of capacity — just 35 percent of historical averages, according to data from the Department of Water Resources.
The three reservoirs are critical components of the water storage and delivery system used for keeping the Delta free of sea water, providing water for farms, fish, wildlife and hydro-electric power, and for delivering municipal water supplies to roughly two-thirds of the state’s population, including the Bay Area, Sacramento and Southern California.
Ernest Conant, regional director for the Bureau of Reclamation, which manages the federal Central Valley Project, said:
“With the extremely low inflow to our reservoirs, we are running out of reservoir storage and other tools to meet all the competing demands.”
The Water Board also issued curtailment orders for 861 water rights holders in the Upper Russian River watershed on Monday and announced that 222 rights holders in the Lower Russian River watershed are likely to see such an order by as early as next week.
Erik Ekdahl, deputy director for the Division of Water Rights, said:
“(Lake Mendocino) is declining much faster than anticipated.”
Without restricting the amount of water drawn from the watershed, Lake Mendocino could be entirely empty by the end of the year, Ekdahl said.
Currently, almost 90 percent of the state is enduring extreme, climate change-driven drought conditions, according to the National Weather Service, and Gov. Gavin Newsom has declared a drought emergency for 50 of California’s 58 counties.
In July, Newsom asked all Californians to voluntarily cut water usage by 15 percent.