The 2021 Water Year: Anything But Normal

By Mychel Matthews and Hannah Ashton, Times News

TWIN FALLS — An uncertain winter snowpack, empty reservoirs on the Upper Snake River, and the prediction of the repeat La Nina weather pattern will force farmers in the south-central Idaho desert to make tough decisions about what crops to grow in 2022.

Crops in the Magic Valley significantly suffered through the past year’s hot, dry growing conditions and growers now worry about next year.

Idaho is in a drought “that is unprecedented in recent memory,” according to the Idaho Department Resources. An exceptionally dry spring followed by a summer heatwave resulted in the driest March-to-July period since 1924.

To date, 2021 is the 15th driest year Twin Falls has experienced since the town’s inception, according to the National Oceanic and Atmospheric Administration. Precipitation totals for the year are well below normal.

In the past eight months, Twin Falls has seen 5.26 inches of rain, said Les Colin, National Weather Service forecaster in Boise. Normal precipitation for that period is 7.64 inches.

Farmers here know they have to make the best use of whatever water is available, whether that means changing their crop rotation to include less thirsty crops or selling hungry livestock that depend on the crops for food.

Carl Pendleton, who grows alfalfa near Shoshone, sold all his cattle in the spring, which was devastatingly dry in many regions.

“It was a disaster,” Pendleton told the Times-News on Friday. His gross income on his alfalfa crop normally exceeds $100,000; this year’s total was $13,000.

Pendleton is the board president of the Big Wood Canal Co., which owns Magic Reservoir and delivers irrigation water to growers downstream, including himself. Because of low reservoir levels, the canal company shut off water on June 10, after 27 days of water delivery.

This was the shortest season since 1977, Pendleton said. A normal irrigation season would last 140 to 150 days.

Often, Magic Reservoir carries 50,000 to 70,000 acre-feet from one irrigation season to the next. As of Friday, Magic Reservoir held about 8,000 acre-feet, canal company Manager David Stephenson said. That’s the lowest depth the canal system can draw from.

An acre-foot is the amount needed to cover one acre with 12 inches of water.

In a normal year, shareholders on the Magic Tract grow such thirsty crops as corn, potatoes, alfalfa and sugar beets, Stephenson said. This year, only a few potatoes were grown, but no corn.

“They got maybe a cutting or two of alfalfa,” he said.

His growers will probably wait until after the end of the year to make planting decisions, Stephenson said. Those decisions will depend on the amount of snow that falls in Blaine County mountains this winter, but he assumes the drought will mean growers will plant a lot of small grains and crops that need very little water.

Stephenson also manages the American Falls Reservoir District No.2, delivering water through the Milner-Gooding Canal that winds northwest from Milner Dam on the Snake River, past Shoshone and ends up in the Malad River west of Gooding.

Irrigation companies that draw water from Milner Dam — including Stephenson’s district, Twin Falls Canal Company and North Side Canal Company — rely mostly on the snowpack in northwestern Wyoming, which generally places them in a better position than canal companies that rely on local snowpack.

American Falls Reservoir No. 2 “shut off at the end of September, two weeks short,” said Stephenson, who has managed the two canal companies for four years.

Twin Falls Canal Co. is still delivering irrigation water but reduced the amount being delivered earlier in the season, canal company Manager Jay Barlogi told the Times-News.

“The winter snowpack peaked two weeks early with 80% of normal moisture,” Barlogi said in June.

A harvested barley field is irrigated Thursday east of Twin Falls to prepare for field work this fall. The Twin Falls Canal Co. reduced water deliveries in the summer in order to extend the water supply through the end of the growing season.

As long as water managers keep growers informed of the district’s plans, growers can adjust irrigation and harvest schedules accordingly, Stephenson said.

As of Friday, the whole Upper Snake River system was at 11% capacity, according to the Bureau of Reclamation.

Mother Nature is a fickle woman.

An inadequate water supply has, from the beginning of the Salmon Tract in southern Twin Falls County, plagued farmers on the tract who depend on water in the reservoir to irrigate their crops.

This year was no exception.

By July, the tract was out of water for its 187 shareholders. The company uses 300 miles of canals and laterals to deliver irrigation water to 25,000 acres.

Salmon Falls Creek Reservoir is now at 3% capacity, with less than 7,000 acre-feet, according to the canal company’s website.

But just four years ago, the Salmon River Canal Co. had too much water. In March 2017, water spilled over the Salmon Dam for only the third time in its 110-year history.

“Having too much water is something we don’t deal with,” former canal company board President Karl Joslin told the Times-News at the time.