Drought to hit irrigators
Water rights priorities set below Magic Reservoir
By GREG STAHL
Express Staff Writer
The outlook for a low water year and rising power costs is
casting a long shadow over Idaho’s approaching summer.
Though scenic, water trickling down
Trail Creek, through Sun Valley and Ketchum, will probably do little to
help downstream irrigators in the summer to come. Express
photo by Willy Cook
With mountain snowpacks as low as they’ve been in
decades, the water forecast is dismal, and Idaho Power Co. has asked for a
$227 million rate increase to cover—among other things—the projected
shortfall at its hydropower generating dams.
But just how bad it will be could depend on location and
weather over the next six to eight weeks. The forecast is for a wet spell
in the near future, but the longer term remains uncertain, according to
the National Weather Service in Pocatello.
In some places, rain will only delay the inevitable.
The Big and Little Wood basins hold about 45 percent of
their average snowpacks. Further, the state water master for the local
water district, Lee Peterson, said he believes spring runoff on the Big
Wood River has already peaked.
"It does not look very promising," he said.
"There’s a very good chance we have peaked out already. If we
should get some real warm rains up there, then we would get a gush coming
down."
Peterson said he believes most of the snowmelt is seeping
into the ground rather than into area streams and rivers.
The Big Wood Irrigation Co. expects to start delivery of
water stored in Magic Reservoir, primarily filled from the Big Wood,
around May 1 or, if wet spring conditions persist, shortly thereafter. The
reservoir now holds only 70,000 acre feet of water, which is about 35 or
36 percent of its capacity.
That’s enough to supply 30 to 45 days of water to
irrigators, canal company manger Lynn Harmon said.
By mid-June there should be only 4,500 to 6,000 acre-feet
left in Magic, he said.
"It looks pretty sad when it gets down to that,"
Harmon said.
The canal company has not asked irrigators not to plant
crops, he said, but to plant crops that consume less water. That means
more oats and barley instead of sugar beets and potatoes, and only one or
two cuttings of alfalfa.
Other small reservoirs face similar dismal circumstances.
The snowpack in the Salmon Falls basin, south of Twin Falls, is at about
71 percent of average, and in the Oakley Reservoir Basin it is 50 percent.
For larger, reservoir-serviced irrigation tracts, the
picture is a little better.
Jackson Lake, on the Snake River in Wyoming, is nearly
full, but Palisades Reservoir, upstream of Idaho Falls, is not likely to
fill. Downstream, the American Falls Reservoir is the only one on the
Snake that‘s full.
Those three reservoirs provide the bulk of irrigation
storage for Magic Valley irrigators.
If the spring remains cool and damp, which would delay the
start of irrigation demand, the stored water will last longer. But
inevitably, some irrigators will not receive enough water this year.
The state distributes water based on seniority, a concept
called "first in time, first in right." Canal companies are on
the delivering end of the equation.
The Idaho Department of Water Resources has established
priority cuts for Big Wood, Little Wood and Silver Creek basins, dating as
far back as June 1885 for Little Wood irrigators. The oldest right on the
Little Wood is April 1877.
The priority cuts for the Big Wood River above Magic
Reservoir are not yet in, but below Magic on the Big Wood, they are set at
April 1905.
The oldest water right on the Big Wood below Magic is
April 1882.
The Twin Falls Canal Co., which relies primarily on
natural flows, expects to begin the season delivering three fourths of a
miner’s inch per acre. One cubic foot per second of water equals 50
miner’s inches.
The expected low water levels will affect more than
irrigators.
Idaho Department of Fish and Game officials say low water
in reservoirs will affect fisheries, possible wiping some out. Spokesman
Mike Todd said officials are particularly concerned about Magic, Mormon
and Fish Creek reservoirs.
As the reservoirs go dry, fishing limits may be lifted to
allow salvage fishing. Already the limits have been lifted on the Big Wood
River below Magic Reservoir.
