REXBURG— With the recent water curtailment order issued by directors of the Idaho Department of Water Resources on May 30, a lot of worry and economic concern has been stirring among the people of Idaho in relation to agriculture. Currently, the Idaho Department of Water Resources has paused its curtailment compliance field inspections and is working to come to an agreement with the groundwater districts in Bingham, Bonneville, Jefferson, and Clark counties. This curtailment impacts groundwater users who hold 6,400 groundwater rights, and potentially impacts some 500,000 acres of farmland.
“Most people have multiple rights, and a lot of times there’s multiple rights even in just one well,” Aaron Dalling the executive director of the Fremont-Madison Irrigation District says.
The curtailment order comes about because of a projected water shortage of some 74,100 acre-feet of water for the Twin Falls Canal Company (surface water users), which holds senior water rights. During times of predicted shortfall, those with senior water rights want to ensure they have the water they need, because of this, under Idaho law, they can make ‘water calls’ over junior water rights users.
Dalling clarifies that whenever there is a potential water shortfall groundwater users are required to follow a methodology order, which falls under a 2016 state water agreement. This order requires groundwater users to be a part of a mitigation plan, or supply that shortfall in storage water so they are not subject to curtailment based on that shortfall. He says the curtailment is usually just for a water season.
“Last year they (IDWR) ran the methodology in April it showed a similar shortfall, 74,000, 75,000 acre-feet, and then in July they reran the methodology order, but because we had a cool wet spring last year the methodology order in July showed that there was no shortfall. They run the methodology order multiple times a year,” Dalling says.
Dalling says the methodology order is run in April and July each year, and there two model types that are run— theSteady State Model, and the Transient Model. This year the Transient state Model was used.
“One of the big issues is that the department changed the way they ran the methodology order, there are two different model types that people reference that you’ll hear. There’s the Steady State Model, and there’s the Transient State Model,” Dalling says. “Prior to 2023 they based the methodology order on the Steady State Model… If there was a shortfall to the Twin Falls Canal Company of 75,000 acre-feet, historically you didn’t have to cut enough water rights that they would get all that 75,000 acre-feet in that same year—it would be over time."
Dalling says some water districts find the mitigation plan, under the methodology hardly workable, but the Madison Water District, the Henry’s Fork Water District, along with water districts in Aberdeen, American Falls, Magic Valley and others find it feasible.
“The Madison Groundwater District, and the Henry’s Fork Groundwater District notified the department back in May that we would mitigate under the 2016 settlement agreement, and that protected us from curtailment,” Dalling says.
For the Madison, and Henry’s Fork water districts the mitigation plan looks like the purchasing of storage water from Henry’s Lake and delivering it directly to Magic Valley canals to offset a portion of their pumping.
“We also purchase water and have it recharged at the Egin Lakes recharge site,” Dalling says.
Dalling says IDWR has to make decisions based on court rulings and Idaho State Law. He says IDWR is primarily made up of hydrologists, geologists, and engineers.
“In defense of the department, they would tell you that they are doing what they’re doing because they’re trying to follow the law, because all of these things have been challenged in court, and the surface water users continue to win in court. The department would tell you that they do what they do because they have to because that’s what the court has directed them to do,” Dalling says.
Dalling says overall there’s a lot of emotion involved with this curtailment issue, and says that he doesn’t believe the Idaho Department of Water Resources is out to get anyone or that it wants to shut off water to 500,000 acres of farmland.
“I think that they’re trying to make the best decisions they can with the information they have. I think it’s similar for the groundwater districts. I think they realize the weight of the decisions that they have to either enter an agreement or not enter it. They feel that. I think on both sides people are working around the clock. I think they’re losing sleep. I think they’re feeling a ton of weight on their shoulders,” Dalling says. “I think everyone is trying to make the best decisions that they can.”