LOS ANGELES (AP) -- A federal judge has thrown out a lawsuit filed by Los Angeles against air quality regulators who are requiring the city to do more to control dust on a lake that was siphoned dry a century ago to provide water for the booming metropolis.
U.S. District Judge Anthony W. Ishii granted a motion Wednesday to dismiss the lawsuit in the latest chapter in a decades-old spat over water rights in the arid region 200 miles north of Los Angeles. The lawsuit was filed last year in U.S. District Court in Fresno.
The conflict began in 1913, when Los Angeles began diverting water from Owens Lake, which then went dry in 1926. The lakebed has since been plagued with massive dust storms and poor air quality despite efforts by the city to keep dust down.
The scandal created by the diversion project was fodder for the 1974 film "Chinatown," and an aqueduct carrying away the water was dynamited repeatedly by angry residents after increased pumping in the 1920s combined with a drought ruined many farms.
Since a 1998 agreement, Los Angeles has spent more than $1 billion to tamp down the dust as part of the nation's largest dust mitigation project, mainly by putting water back into more than 40 square miles of the lakebed.
The utility is currently working to control dust on another 3-square-mile parcel, said Ted Schade, air pollution control officer for the Great Basin Air Pollution Control District.
The city alleged in its lawsuit that 2011 orders from the pollution control district to further increase the mitigation were excessive and questioned whether Los Angeles was even responsible for problems in that area of the lake.
Joe Ramallo, spokesman for the Los Angeles Department of Water and Power, said in an email Thursday that the judge's ruling was largely procedural and didn't address the core issue.
"We remain committed to exploring all available means for stopping the enormous waste of California's scarce water supply and protecting consumers from the wasteful spending of Owens Valley regulators," he said.
The city has a lawsuit still pending in state court and has proposed a project that would reduce water use at Owens Lake by 50 percent by using vegetation, ground water, gravel and other means to reduce dust.
The federal lawsuit, which also named the California Air Resources Board, the U.S. Environmental Protection Agency and the U.S. Bureau of Land Management, had asked the court for relief from the "systematic and unlawful issuance to the city of dust control orders and fee assessments."
The department said last year when it filed the action that additional dust control would cost up to $400 million when each ratepayer already provides $90 a year to improve air quality around Owens Lake. The city uses 30 billion gallons annually -- enough to fill the Rose Bowl each day to overflowing for one year -- to keep dust down, the city said.
The latest legal ruling could come at a particularly bad time for the city.
Survey results released Thursday showed snow pack in California was at 17 percent of normal, an ominous situation for a state that depends on a steady stream of snowmelt to replenish reservoirs throughout the summer.
Owens Lake air quality regulators agreed this summer will be particularly dry and are working with the city to use less water on dust, said Schade, whose pollution district covers Inyo, Mono and Alpine counties in a vast region northeast of Los Angeles.
One solution, in addition to placing vegetation and gravel, includes spot-treating areas that are producing the most dust, he said.
"We realize that this is a dry year," Schade said. "We acknowledge the fact that they are putting water on the lakebed, and we recognize the value of that water."
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