Clear Lake home to Lost River, shortnose sucker

The dam was completed in 1910, and its original purpose was to reduce the amount of water in Tule Lake, making it possible to reclaim more marshlands for farming. The dam was replaced in 2002, according to the Bureau of Reclamation website.

Evaporation rates at Clear Lake make it an inefficient storage reservoir. The lake's maximum depth is about 20 feet, and while the lake has the capacity to store 527,000 acre-feet of water, as of Monday, there were 69,810 acre-feet of water in the lake.

When two species of sucker were listed on the Endangered Species List, the Bureau had to change the way it operates Clear Lake to comply with legally mandated elevations, said Bureau of Reclamation spokesman Kevin Moore.

"Every effort is made to provide releases when available and comply with federal regulations," he said. "Drought conditions like we are currently experiencing further complicate an already difficult challenge."

Endangered sucker

Endangered species of sucker live in Clear Lake and spawn in Willow Creek, the only available spawning habitat connected to the lake.

A U.S. Fish and Wildlife biological opinion dictates the minimum lake elevations that Lost River and shortnose suckers need to survive.

The opinions lay out a plan for reducing the amount of water in Klamath Project reservoirs throughout the irrigation season without harming fish populations.

This year, the lake is already losing water, no irrigation deliveries have been made and none are expected.

The lake's elevation, 4,522.77 feet above sea level on Monday, was below its elevation of a month earlier, despite wet April weather. The 0.10-foot difference represents a loss of more than 1,500 acre-feet of water.

The Fish and Wildlife Service biological opinion says in a "critically dry" year, the lake's elevation should be no less than 4,524.6 feet at the end of April. By the end of September, the elevation has to be above 4,520.6 feet.