EPA Cites Bad Air at Mono Lake

The U.S. Environmental Protection Agency has proposed re-designating a scenic section of Eastern Sierra High Desert surrounding Mono Lake as being in violation of federal air quality standards because of dust raised off the lake shore.

The federal action last week was the first step in the process for officially naming the lake basin as a violator of federal air quality standards. The re-designation is subject to a 30-day public comment period, after which the EPA could make the move official. That would require that the problem be fixed within six years.

The EPA based its decision on monitoring of dust clouds at the picturesque saline lake. The small particles of dust raised by winds can lodge in the lungs and are considered especially hazardous for children, the elderly, or those with respiratory problems, the agency said.

Only about 20 people live on the north side of the lake, which is the area most often blasted by dust storms. But even visitors caught in one of the dust storms could experience difficulty breathing, according to Duane Ono, deputy air pollution control officer for the Great Basin Unified Air Pollution Control District in Bishop.

Ono said that exposed areas of lake bed were the primary source of the dust storms. Decades of water diversions from several of the lake’s feeder streams by the Los Angeles Department of Water and Power, which owns the water rights, have lowered the lake’s surface by 45 feet and dried up large sections of former lake bed.

“Our studies show that the problem is caused almost completely by wind-blown dust coming off the Mono Lake shoreline,” Ono said.

Court rulings that ordered the lake’s level to be raised have compelled the State Water Resources Control Board to redefine the DWP’s water rights at the lake. Most observers expect the board to require that the lake level be raised to preserve the lake’s ecosystem.

But the added requirement of solving the area’s dust problem could mean that the lake would have to be raised to an even higher level, further curtailing the DWP’s access to the water.