With statewide shortages looming, Southern California water agencies are scrambling to create a detailed plan of how much water they - and each of us - would get if supplies are cut.

The region could lose 30 percent of its Northern California water supplies next year because of a court ruling to cut use of the pumps that send Northern California rainfall and snowmelt south to the semi-arid southland.

The pumps, which provide much of the region's water, are killing an endangered fish, prompting the federal courts to step in.

A number of smaller water agencies in Southern California have historically fought over their rights to water during shortages, and old arguments over which communities should endure deeper cuts could resurface as officials work out shortage plans.

So far, the area's larger water providers are working together to make those plans and to stave off a shortage rather than fight about who should get more water should one occur, said Jim Bond, a board member of the San Diego County Water Authority and the Metropolitan Water District. Metropolitan is Southern California's main water supplier.

"It's not unlike a forest fire," Bond said. "You know, you don't see the foxes go after the chipmunks when there's a forest fire. They're all running to get away. Everyone is running together to solve this problem.

"Whether we'll all stay that way is hard to tell," he said.

Metropolitan officials said last week they are working on a shortage plan to bring to the district's board next month.

Metropolitan supplies water to nearly 18 million people represented by 26 cities and water agencies, including the Water Authority, in six counties.

Brandon Goshi, a Metropolitan manager who has been working on the plan, said the proposal would revolve around three basic ideas: limiting the harm that water supply cuts could have on retail consumers and the economy; recognizing the steps Metropolitan's member agencies have taken to develop their own water sources; and taking into account how much agencies relied upon Metropolitan for their water.

Difficult process?

Creating a plan to divvy up Southern California's water equitably if Metropolitan cuts supplies could be difficult because not all regions' water needs are equal.

Some areas' water agencies have their own partial water supplies, allowing them to rely less upon Metropolitan than other agencies. If Metropolitan were to cut water equally to all agencies, some areas would be affected more than others.

For example, the city of Los Angeles built its own aqueduct to Owens Valley early in the 20th century, creating a pipeline that delivers half of Los Angeles' water supplies every year. The city also has groundwater supplies of its own. Consequently, Los Angeles only buys 34 percent of its water supply from Metropolitan.

In contrast, San Diego County, which has few reservoirs and doesn't have the kind of porous rock needed for groundwater storage, buys 73 percent of its water for county residents from Metropolitan.

That means the San Diego area would lose a greater percentage of its overall water supply than Los Angeles would if Metropolitan issued an across-the-board cut.

Goshi said the formula that Metropolitan plans to propose to board members a system that would take that discrepancy into account and would increase rates for agencies who can't live within suggested water budgets.

Water rates already are on the rise in most of the county, where local agencies have begun passing on an expected fee hike of 5 percent to 10 percent from Metropolitan.

Many local growers face certain water cuts beginning in January under a program that lets farmers buy discounted water in exchange for being the first to cut back in dry times.

Some cry foul at equal cuts

Some water officials suggest imposing across the board cutbacks and making agencies bid on water for their customers could help the region deal with a shortage.

But forcing communities to pay even more for water when supplies dwindle is a dangerous option for nonwealthy communities and areas that have not created their own supplies, said Glenn Peterson, a board member from the Las Virgenes Municipal Water District, during a planning meeting with Metropolitan last month. That district covers parts of the Los Angeles area and has none of its own water supplies.

"I don't think we all want to compete with Beverly Hills," Peterson said. "I think we have to be above that."

But areas that have invested in their own supplies say uniform cuts would be fair to districts that have invested in finding and storing more of their own water.

Larry Dick is a board member from the Municipal Water District of Orange County, which gets half of its water from its own local supplies.

Dick suggested that Metropolitan could just issue 10 percent across-the-board cuts, then say "but we have more water. And you can bid for it."

Dick said he raised the idea to protect cities and agencies that had made "significant investments" to create their own water supplies and reduce their reliance on Metropolitan.

Transfer deal put SD County in better shape

Even though it still relies heavily upon Metropolitan, the San Diego County Water Authority is one of those agencies that spent a lot of money to find new supplies and cut its dependency on Metropolitan.

In 2003, the Water Authority completed a deal to buy up to 65 billion gallons of water a year from Imperial Valley farmers for about $50 million for 45 to 75 years. The deal ramps up slowly until it reaches the full 65 billion gallons a year in year 19, when it will provide about 22 percent of the county's total water supply.

The Water Authority worked for eight years to complete that deal, and started chasing it out of frustration after the last time Metropolitan had to issue mandatory water supply cuts - during the state's last big drought in 1991.

Drastic cuts were avoided during that scare when what officials called "Miracle March" rains broke all around Southern California, ending the drought.

Some say L.A. could grab local water supplies

In the discussion of how Metropolitan might divvy up Southern California's water supplies, there is a potential joker in the deck - an arcane Metropolitan water-allocation system the agency says it would never use, called "preferential rights."

The Water Authority railed against that system for years, and even sued unsuccessfully to have it changed, saying it was a threat that could let other agencies "steal" water from San Diego County residents.

The system was created as part of Metropolitan's charter when the state Legislature created the agency in 1928.

It guarantees Metropolitan's member agencies a right to the agency's water based upon how much each agency contributed to Metropolitan in property taxes.

Under the system, San Diego County residents "own" about 16 percent of Metropolitan's water even though they annually buy about 28 percent of the agency's supplies.

By contrast, Los Angeles owns more than 22 percent even though it typically buys about 7 percent.

Water Authority officials have said Los Angeles could make a telephone call and Metropolitan would divert water that San Diego County residents use to Los Angeles.

Could preferential rights be invoked if shortages appear and Metropolitan hasn't adopted an allocation plan?

Metropolitan managers say they would never invoke the system. Others say it wouldn't be up to Metropolitan.

Goshi, meanwhile, said he was confident the board would adopt a plan - even if though it hasn't before.

"Here's the difference, we have a threat," he said. "This is different than trying to develop a theoretical plan."

Contact staff writer Gig Conaughton at (760) 739-6696 or gconaughton@nctimes.com.