Salton Sea Eyed as Source of Widespread Odor

Air quality officials in Southern California are investigating whether the Salton Sea is the source of a rotten-egg odor widely reported across a region stretching from the Inland Empire to the San Fernando Valley.

The South Coast Air Quality Management District deployed field inspectors in numerous locations and was monitoring air samples to determine whether the smell was related to a recent fish die-off at the Salon Sea.

“Several factors indicate that the Salton Sea may have been the source of these odors,” Barry Wallerstein, executive officer for the district, said in a statement. “However we do not have any definitive evidence to pinpoint the Salton Sea or any other source yet.”

Several sources have reported hot weather and a possible release of bacteria from the bottom of the sea due to winds there. Those conditions could cause strong sulfur odors.

In addition, strong thunderstorm activity in the Salton Sea area and resulting high winds from the southeast could have pushed odors into the Los Angeles basin. However, it is highly unusual for odors to remain strong up to 150 miles from their source, Wallerstein said.  

The district received about 200 complaints of sulfur- and rotten-egg odors on Sept. 10. Most callers were from the Coachella Valley and other portions of Riverside County as well as San Bernardino and Los Angeles counties. Only a few calls came from Orange County.

Officials said a strengthening onshore breeze expected Tuesday may keep any additional odors from spreading as far west as they did on Monday.

In the past week, high temperatures reduced oxygen levels in parts of the Salton Sea, causing fish to die and settle to the bottom, where they decomposed with other organic material.

Fish die-offs are not uncommon at the Salton Sea, a shallow lake that occupies a desert basin known as the Salton Sink in the southeastern corner of California. The sea, which covers a surface area of 376 square miles and is fed primarily by agricultural drainage, is vulnerable to dramatic changes in elevation due to reductions or increases in inflows to the sea.