California water officials are on the verge of making an unusually drastic pronouncement in response to the ongoing drought: Ordering hundreds of water agencies, farmers and other property owners to stop diverting water from rivers in which they have long-standing water rights.
Within a matter of days, the State Water Resources Control Board is expected to issue curtailment orders to "junior" water rights holders, meaning they would be required to stop diverting water from streams and rivers, or reduce those diversions.
The intent is to heed state law, which requires that available water, during times of scarcity, be reserved for those with "senior" water rights and for the environment.
In a similar order, the Santa Clara Valley Water District last month required farmers in Santa Clara County to stop taking water from surface streams and creeks. Most have wells on their properties, however, which provide backup water supplies.
The agency recently posted data on its website estimating when curtailments might be required in certain watersheds, depending on runoff conditions, water demand and the type of water rights. Such orders are now "pending" for junior water rights -- those issued after 1914 -- on nine rivers and their watersheds: the Stanislaus, Tuolumne, Merced, Yuba, Kern, Kings, Kaweah, Tule and Middle Fork Eel.
"Pending" means the order could come any day, said John O'Hagan, supervisor of water rights enforcement at the water board. Such widespread curtailments have not been ordered since the drought of 1977, he said, and are virtually a sure thing this year.
"Based on our analysis, I would think there will be curtailments of certain water rights," O'Hagan said. "Because the snowmelt is not there, the precipitation is not there."
The city of Sacramento, which draws its water from the Sacramento and American rivers, could be affected as soon as May 15. That's when the state may order curtailments for other post-1914 water rights, including the Russian River above Healdsburg and the entire watershed of the Sacramento and San Joaquin rivers, the largest watershed in the state.
If that happens, the city may call for more severe water rationing than the 20 percent conservation order already imposed, said city spokeswoman Jessica Hess.
The city also has some pre-1914 "senior" water rights that would not be affected by initial curtailments, though conservation would be required to continue serving the whole city using these rights alone.
Many cities in the Sacramento region lack water rights, and buy their water from the state and federal governments. Those contracts could be affected as well, because the state and federal governments have water rights that also could be curtailed.
In most cases, the curtailment orders won't mean the water supply is completely shut off. Like Sacramento, most water users have other supplies to fall back on if their primary water right is cut back.
Some can pump groundwater or rely on water already held in reservoirs. Even so, curtailments will require sacrifice, particularly among some farming communities, said David Guy, president of the Northern California Water Association, which represents property owners and water agencies in the Sacramento Valley.
"There's definitely going to be some pockets where these curtailment notices will hit people hard," said Guy. "If they don't have access to other types of water, then they're going to be affected."
The looming curtailments indicate how severe the drought has become. The statewide snowpack was just 20 percent of average as of Wednesday, meaning there won't be a lot of runoff in streams over the long, hot summer months. The snowpack already is melting rapidly, thanks to early hot spells.
Stream flow gauges maintained by the U.S. Geological Survey also tell the tale. Out of 230 gauges in California, 69 percent on Wednesday reported "below normal" flows, up from 46 percent a month ago.
Water rights are held by a broad spectrum of California entities, from the individual rural homeowner to large users such as farmers, energy companies and state and federal agencies that deliver water to millions of urban residents. Normally, a water right represents a very secure supply because it generally allows pumping directly from a stream at will. No one else controls a valve or demands a fee. Although many rights include limitations on water volume and time of year, it is essentially a guaranteed supply -- except in very bad drought years.
The purpose of the first curtailments is to preserve water for "senior" users, which have a legally superior right to access any water that might be available. But by June, the water board estimates, even these senior diverters could face curtailments. The goal at that point would be to preserve water for essential health and safety purposes, and for wildlife and habitat.
Water used for hydroelectric power generation would be exempt from curtailment, because that water merely passes through turbines and is returned to the stream. A curtailment also would not affect water already stored in reservoirs, although additional storage would not be allowed, O'Hagan said.
Under the order, anyone subject to a curtailment who has no other supply would still be allowed to divert as much as 50 gallons per day, per person, for "public health and safety needs."
Staff writer Paul Rogers contributed to this report.