Courtesy of Kacee Lathrop
Calls to release an additional 1,000 acre-feet of stored irrigation water from Willow Creek Reservoir in Eastern Oregon will not significantly impact the local environment, according to a draft report issued March 2 by the U.S. Army Corps of Engineers.
The Corps operates Willow Creek Dam near Heppner, Ore., primarily for flood control, irrigation and recreation. Farmers currently receive 2,500 acre-feet of water from the reservoir during the irrigation season, from April 16 to Oct. 31, though the Willow Creek District Improvement Co. has requested an increase to 3,500 acre-feet, which would relieve stress on groundwater wells.
Willow Creek Reservoir already stores 3,500 acre-feet of water for irrigation, said Brian Thompson, district president. The change merely allows farmers and ranchers to access the full amount.
“Right now, the main reason we want to go back after this is groundwater,” Thompson said. “Our groundwater for our homes and cities is going the wrong way.”
Long-term irrigation water releases from the reservoir are established by an environmental assessment completed by the Corps in 2008. A recently completed supplemental analysis found releasing an additional 1,000 acre-feet would have no significant environmental impact — meaning the Corps would not need to conduct a full environmental impact study under the National Environmental Policy Act.
Public comment on the draft findings will continue through Monday, April 2. Lauren Bennett, a spokeswoman for the Corps Portland District, said the agency may update its recommendation based on the comments received.
Irrigation water from Willow Creek Reservoir serves roughly 11 landowners over 20 miles between the cities of Heppner and Ione in Morrow County. Thompson said the district does not intend to put any new acres in production, but rather supplement existing acres used to grow alfalfa, grain and high-value vegetables such as potatoes.
“It just gives us access to a renewable, calculated amount of water,” he said.
The district applied for the change in 2015 to the Bureau of Reclamation, which handles water storage contracts for the reservoir. Three years later, the Corps has determined there would “little to no incremental effect” on water quality, vegetation and wildlife.
The biggest short-term impact may be lower reservoir levels between May and January, the report states, which could potentially impact boating and fishing. For the last two years, the Oregon Department of Fish & Wildlife has released several thousand extra large trophy trout into the reservoir, part of a statewide program to promote economic development in rural areas.
With additional water releases from the reservoir, the boat dock may not be usable for several weeks in the summer during drought years. However, Thompson added the reservoir historically experiences seasonal blue-green algae blooms during this period, when people are urged to stay away from the water for health and safety reasons.
“We have a blue-green algae bloom before we even start drawing (for irrigation), usually,” he said. “The water turns to pea soup.”
Bennett said the Corps has acknowledged that water quality may worsen at the reservoir with increased irrigation releases, leading to an increase in blue-green algae blooms. However, degraded water quality “would not rise to a significant level under NEPA.”
The agency also consulted with the Confederated Tribes of the Umatilla Indian Reservation, which discussed its intention to reintroduce steelhead into Willow Creek “at some future time,” though the Corps says potential reintroduction of the fish remains uncertain.
Thompson said increasing the amount of surface water available to farmers will actually have a net positive environmental impact, protecting increasingly vulnerable groundwater in an area that receives little annual precipitation.
“I have three wells myself, and I don’t intend to run them unless I have to,” he said. “That would be a huge environmental benefit.”
Comments on the Corps’ draft assessment can be sent to the Corps Portland District office, care of District Engineer Kathleen Wells, P.O. Box 2946, Portland, OR 97208-2946, or email firstname.lastname@example.org.