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A national conservation group plans to blow up 2 miles of
levees Tuesday 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.
Tuesday'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% 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." |
