Levees face blasts to help lake, fish

TUESDAY, OCT. 30, 2007

A national conservation group plans to blow up two miles of levees today on Oregon’s Upper Klamath Lake in an unprecedented move to improve wildlife habitat, water storage and water quality downstream.

The Nature Conservancy aims to restore almost 5 square miles of marsh in an area vital to two rare fish species. Crews will set off 100 tons of explosives buried in four half-mile sections of dikes.

Water from the lake then will rush through the gaps to flood wetlands lost 50 years ago when the Williamson River delta was drained for farming. The conservancy has bought the croplands and removed them from production.

The explosions, in four bursts over five minutes, will throw soil 150 feet up and 300 feet out, says Mark Stern, director of the conservancy’s Upper Klamath conservation program.

“It’s not going to be this big volcanic explosion, but you will feel the earth move a little bit,” Stern says. He says loud booms will go off before the actual explosions to scare away fish and other wildlife.

The $9 million project, 12 years in the making, is backed by federal and state agencies and a host of groups because it will both aid wildlife and increase the capacity of the Upper Klamath, Oregon’s largest freshwater lake. The lake is home to the shortnose sucker and Lost River sucker, both declared endangered under federal law 19 years ago. It also is the source of the Klamath River, a lifeline for 1,400 irrigation farmers and for threatened Coho salmon downstream.

“By breaching these levees and restoring wetland, we essentially are making Upper Klamath Lake a bigger water body, with more storage available for downstream,” Stern says. “It will also create tremendous breeding habitat for water birds – pelicans, black terns, sandhill cranes and waterfowl” that migrate along the Pacific Flyway.

Helping the fish now – the new marshes will act as a nursery for young suckerfish – could ease a long-running battle over water downstream. In a severe drought several years ago, the lake level fell so low that water managers had to cut off the flow to farmers to protect the fish. Angry protests followed. Lawsuits over the lake, river and fish continue today.

Water releases for farming are likely to continue jeopardizing the three fish species, the federal Bureau of Reclamation reported last week in an assessment of irrigation operations through 2017.

Today’s blasts should boost the lake’s volume by almost 5.9 billion gallons. Explosives are being used instead of bulldozers because the levee soils are too unstable. Earthmovers were still used over the past two years to remove the upper 60 percent of the berms – about 1.75 million cubic yards of dirt – to make the final job easier.

Once the dust settles, aquatic plants such as hard-stemmed bulrushes will begin to reclaim the marsh naturally.

“The recipe for growing wetlands is pretty straightforward,” Stern says.

“Just add water.”


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