Groundwater users will be required to find mitigation water for the Twin Falls Canal Company and other surface water users found to be injured in a long-running water delivery call, Idaho Department of Water Resources Director Dave Tuthill announced Friday in his final order on the topic.

The order resolves, at least for the moment, a water dispute that began in January 2005. Members of the Surface Water Coalition - including the Twin Falls and North Side canal companies, among others - sought to shut off groundwater users who they said were depriving them of their full, senior water rights.

Other members of the coalition include the A&B, Milner, Minidoka and Burley irrigation districts and American Falls Reservoir District 2.

Hearing officer and former Idaho Chief Justice Gerald Schroeder found in an April recommendation that the Twin Falls Canal Company in particular had been injured, and also questioned some of the procedures followed by IDWR. In Friday's order, Tuthill wrote that he agrees with a number of the subjects addressed in Schroeder's recommendation while taking the chance to defend several actions taken by himself and previous Director Karl Dreher.

For example, Tuthill argued for the continued use of replacement water plans as an administrative tool. Some water users had previously said the plans should be treated following the more thorough process used for full mitigation plans. But Tuthill wrote that the plans give him a way to ensure both sides are treated fairly during a pending call - senior users get their water, while junior users are not "irreparably harmed."

Without the plans, he wrote, "junior ground water users could have been curtailed (shut down) from the time the May 2005 Order was issued until a plan was filed and an order on the plan issued."

Along the same lines, he also wrote that carryover shortages - or shortages in the amount of water stored from one season to the next - should be remedied in the season of the shortage. It's too hard to tell in advance whether senior users will lose water, he wrote, citing 2006 and 2008 as years when shortages were expected but did not happen.

Besides ordering the mitigation, Tuthill also wrote that he would revamp the current approach for calculating harm caused by missing water. The current approach, known as "minimum full supply," will be renamed "reasonable in-season demand" and a separate order before the end of this year will detail the new approach, he wrote. The order will also address carryover needs for 2009, and parties will have the chance to ask for a hearing, he stated.

Water users on both sides were still reviewing the document Friday afternoon before providing comment on it. Schroeder's April recommendation was welcomed by the coalition as confirming its rights, while the Idaho Ground Water Appropriators deferred comment until the release of Tuthill's order.

The order will not take effect until the parties involved have their chance to appeal it to the department. Petitions can be filed within 14 days, and IDWR is required to respond or deny them within 21 days of submission. The order can also be appealed to the court system within 28 days.

Nate Poppino may be reached at 208-735-3237 or npoppino@magicvalley.com.