Heat, rain suspected in fish kill at Suffolk lake

SUFFOLK

The state is trying to figure out what all but wiped out the fish population of a 50-acre lake over the weekend.

Residents around Sleepy Lake, a private lake in the northwestern part of the city, awoke Saturday to a blanket of dead fish on the water, said Dennis McBride, chairman of the lake and dam committee of the homeowner s association.

"We don't know if we got a hundred percent fish kill - but pretty damn high," McBride said Monday.

A fisheries biologist from the Virginia Department of Game and Inland Fisheries arrived Monday. Officials from that agency and the Department of Environmental Quality speculated the kill was a natural result of a sudden and rapid depletion of oxygen in the water.

The incident followed a string of hot weather capped by a heavy rainfall on Friday night. That's a classic scenario for an oxygen-depletion fish kill, said Tom Madigan, an underground storage tank manager for the Department of Environmental Quality.

The warm weather promotes the growth of algae, which consumes oxygen when it dies. The lake is already low on oxygen at night, so Friday's rainfall likely churned up the oxygen-depleted water on the bottom of the shallow lake and made things even worse for the fish, said McBride, who spoke with the investigating biologist.

Fish kills are not uncommon in the summer.

"This is the third one that I know of that's been reported this year," said Gary Martel, director of the fisheries division for Game and Inland Fisheries. "It's something that naturally occurs."

Sleepy Lake covers about 50 acres and reaches about 5-1/2 feet at its deepest, McBride said. About two dozen people spent hours Sunday trying to help clean up the mess, he said. They used at least 100 large trash bags to load up as much as they could and threw many of the larger fish on land, he said.

It was a discouraging sight for the residents, who spent about $8,000 to restock the lake following another large fish kill in 2001, McBride said.

That incident followed a local caretaker's use of copper sulfate to kill algae on the lake, which in turn contributed to sudden oxygen depletion in the water.

McBride, who wasn't present for the 2001 incident, said he had the homeowner s association stop using copper sulfate.

Now the residents are cleaning up after another kill and waiting for the remaining dead fish to sink. The smell has improved from the weekend, McBride said.

"It's a lot better now," he said. "But it ain't pretty."

Dave Forster, (757) 222-5563, dave.forster@pilotonline.com