Fertilizer-Tainted Water Blamed : Fish Kill May Indicate Lake Laguna Is Dying

Investigators tentatively concluded Friday that a massive fish kill in the county’s only remaining natural lake was the result of runoff of fertilizer-laden water that caused the fish to suffocate.

Hundreds of dead bass and carp were found this week in Lake Laguna, in Laguna Canyon, after residents in the nearby Leisure World retirement community complained about a putrid smell.

Biologists and water quality specialists hired by the Irvine Co, which owns the 12-acre lake near the northernmost border of Laguna Beach, began searching the shoreline and testing water Friday.

The dead fish appear to be a confirmation, according to county and Irvine Co. officials, of fears that the county’s only natural lake may be dying because of drought conditions and water drainage from nearby Leisure World.

Some residents of the Laguna Hills retirement community said a stench emanated from the lake several days ago.

“I thought a squirrel died in my back yard,” said Susan Gilkerson, whose Bahia Blanca home overlooks the lake. “It was the fish.”

At least one Leisure World resident phoned county health department officials on Thursday after she noticed the bloated bodies of hundreds of fish floating in the usually pristine lake below her home.

At first “they looked like a lot of leaves floating in the water,” Leisure World resident Betty Anderson said. “It was just so sad to see them floating there, dead. The poor little fish. I just thought that maybe they were poisoned.”

Although tests are incomplete, county officials and consultants for the Irvine Co. said they believe that the fish died because fertilizer-rich water from Leisure World landscaping has been filling the lake with oxygen-eating microbes.

“We want to do whatever we can to help clean this mess up,” Laguna Beach City Manager Kenneth C. Frank told Irvine Co. officials as they inspected the shoreline Friday afternoon. The southern shoreline of the lake is within Laguna Beach.

Irvine Co. spokesman Bill Gartland said rowboat crews next week will begin scooping up the dead fish that are already decomposing among the bulrushes of the lake.

The lake is one of three sister ponds that lie in unincorporated territory near Laguna Canyon Road, about 100 yards north of the Laguna Beach border. Because of drought conditions, two of the lakes have dried up, but the finger-shaped Laguna Lake still contains about 19 feet of water, county officials said.

Unlike many lakes, Laguna lake is not replenished by rivers. It is fed only by runoff from storms and Leisure World, said John M. Tettemer, a consultant hired by the Irvine Co. Consequently, the water is not continuously fed oxygen.

Tettemer, who has been studying the lake’s biosystem for the Irvine Co. for several years, said the company has recorded two mass killings of fish twice in the past 10 years because of oxygen depletion in the water.

“It is not unusual,” he said about the dead fish. “It is just unfortunate.”

The kill comes days before the Irvine Co. is scheduled to release an environmental impact report on the area that, among other things, details a plan to turn over control of the lake system to the county.

As part of development plans for the 2,150-acre Laguna Laurel Planned Community along Laguna Canyon Road, the Irvine Co. has agreed to give 550 acres for establishment of a regional park, Irvine Co. and county officials said. Transfer of the land to public control, however, could take up to five years to complete, officials said.

The impact report’s “Lake Management Plan,” drafted by Tettemer, warns that water runoff from Leisure World and the surrounding hills is killing the lake.

The lake management plan suggests that the company build a bypass system that directs Leisure World water away from the lake and stop allowing cattle to graze near the shoreline.

“This is getting really serious,” Tettemer said, describing how the once green water of the lake has turned brown in a few weeks. The discoloration suggests that the lake may die without intervention, Tettemer said.

Donald R. Collacott, a manager with the county Environmental Management Agency said the lake is rapidly deteriorating.

“We’ve known for a long time that the lake is in very poor shape,” said Collacott, a member of the county team negotiating for public acquisition of the lake.

“It’s a real shame,” he said. “It bothers me quite a bit.” But, he added, county officials have been unable to do anything to save the privately owned lake.

Tettemer said he expects that by midweek results of tests on water samples that were collected Friday would indicate how bad the water quality is.

He estimated that under the best conditions, it could take as long as four years for the lake’s ecosystem to put itself in balance again. But if the drought continues, it could take much longer, he said.