[env-trinity] Low flows in Shasta River stalling chinook in pools
Mark Dowdle - TCRCD
mdowdle at tcrcd.net
Mon Sep 28 10:04:52 PDT 2009
*Concerns pool over salmon*
*By John Driscoll*
A heavy run of Chinook salmon into a parched Klamath River tributary
have fishery managers watching for signs of a possible fish kill and
working to get additional water into the river.
Since Sept. 4, at least 1,200 fall Chinook have passed through the
Shasta River weir, with another 100 per day expected. Radio tags on some
of the fish have shown that all of the fish are packed into pools in a
1.5- to 2-mile section of the river, said California Department of Fish
and Game biologist Mark Pisano.
The Shasta River has seen very low flows this year, at least partly
because of an ongoing drought. But conservation groups have also pointed
to regular irrigation withdrawals as depleting flows, and Fish and Game
has worked out agreements with irrigators to cut back on the amount of
water they use before the end of the season on Oct. 1.
”We're very near a tipping point,” Pisano said.
The concern is that if warm-water-related diseases were to break out,
crowded conditions could spread the diseases through the fish rapidly
and devastate a strong run of salmon. Pisano said that cool mornings
have helped prevent the water from being unbearable for fish. He said
that a handful of fish have died -- but not more than what is typically
associated with natural mortality from the rigors of the migration from
the ocean into the middle Klamath River.
California Department of Water Resources Shasta Valley Water Master Ira
Alexander said that his hands are tied
by court adjudication over water rights in the basin, called the Shasta
”We only have the authority to enforce the decree,” Alexander said.
Shasta Valley Resource Conservation District Administrator Adriane
Garayalde said that some irrigators are scaling back their diversions,
which is easier with new systems than old systems. She said that another
diverter shut off last night, and the water reduction should begin to
show in the lower river soon.
”We've been trying to do more,” Garayalde said, “but the problem is
we're just in a really, really dry year.”
There are about 30,000 irrigated acres in the Shasta River Valley, most
of which are planted with alfalfa and grain.
Agreements brokered by Fish and Game with irrigators to leave more water
in the river may now be beginning to take effect, Pisano said, and the
department will continue to seek more water. Pisano said that those
actions should help improve conditions.
”As conditions are right now, we're at the higher end of what they can
deal with,” said Malena Marvin with Klamath Riverkeeper, a conservation
group monitoring the situation.
The group raised concerns about extremely low flows in the Shasta and
Scott rivers in late summer before salmon began moving into the Klamath
tributaries. Marvin said that it's critical to do something before a
fish kill starts.
Marvin said that such a strong run of fish should not be squandered by
poor water management, especially in light of the recent restrictions on
ocean salmon fishing over the past two years.
Biologists have been on higher alert for the possibility of a fish kill
in the Klamath River basin since 2002, when low flows and warm water
kept a big run of salmon packed into cold-water pools. A disease
outbreak that followed killed at least 68,000 Chinook salmon that year.#
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