By: Randy Budge, T.J. Budge

On June 30, 2015, a historic settlement agreement was entered into between groundwater users and surface water users to permanently end conflict over use and management of Idaho’s vast Eastern Snake Plain Aquifer (ESPA). Nearly the size of Lake Erie, the ESPA supplies water to roughly two million acres of farmland and dozens of cities and industries across southern Idaho. About half of that farmland is irrigated with groundwater pumped from the ESPA while the other half is irrigated with surface water from the Snake River that is supplemented with groundwater that discharges from the ESPA into the Snake River via springs located primarily in the American Falls and Thousand Springs areas. The settlement resolved more than a decade of contentious litigation between surface water and groundwater users. It calls for increased aquifer recharge funded by the State of Idaho and diversion reductions by groundwater users designed to stabilize and over time improve groundwater levels

Groundwater levels in the ESPA have been declining since the 1950s due the conversion from flood to sprinkler irrigation, the advent of groundwater irrigation, and persistent drought. As groundwater levels declined, so have spring discharges from the ESPA into the Snake River, thus reducing the water supply available to senior surface water rights. This spawned a meteoric conflict as canal companies in the Magic Valley and fish hatcheries in the Thousand Springs area called on the Idaho Department of Water Resources (IDWR) to shut off junior groundwater pumping in an effort to increase spring and surface water flows.

The settlement was entered into between seven large canal companies known collectively as the Surface Water Coalition (SWC) and ten groundwater irrigation entities represented by Idaho Ground Water Appropriators, Inc. (IGWA).The primary objectives of the settlement are to (1) mitigate injury to the SWC, (2) provide a “safe harbor” from curtailment to participating groundwater users, (3) stabilize the ESPA to protect and preserve water supplies for both surface and ground water users, and (4) minimize economic impacts to individual water users and the economy of the State of Idaho arising from water supply shortages.

The settlement contains near- and long-term actions. The near-term actions required groundwater users to deliver 110,000 acre-feet of water to the SWC in 2015, continue delivering surface water to certain lands that had historically been irrigated with ground water, and pursue legislation to memorialize State support for the settlement. The groundwater users fulfilled these obligations.

Long-term, the settlement requires ground water users to: (a) reduce their diversions from the ESPA by 240,000 acre-feet annually—a reduction of between 12 and 13 percent over historic water use; (b) lease and deliver to the SWC 50,000 acre-feet of storage water annually; (c) continue delivering surface water to certain lands historically irrigated with groundwater; (d) not irrigate sooner than April 1 or later than October 31; and (e) install meters on all groundwater wells by 2018.

The settlement has been approved by IDWR as a mitigation plan, protecting groundwater users from curtailment so long as they comply with the terms of the settlement.

In addition, the State of Idaho committed to permanently recharge 250,000 acre-feet into the ESPA on an annual average basis. This commitment was confirmed in 2016 by a joint legislative resolution along with the appropriation of necessary funding.

The settlement establishes groundwater level benchmarks and a recovery goal for the ESPA. The recovery goal requires that the water level in the ESPA be returned to the average water level from 1991-2001 by the year 2026. In the interim, the ESPA water level must be stabilized at the 2015 level by 2020 and increased to a point halfway between the 2015 level and the ultimate recovery goal by 2023. If these benchmarks or the recovery goal are not achieved, groundwater users will be required to take adaptive measures to achieve the goal. However, once the goal is achieved, groundwater users may be able to ease restrictions on water use so long as the ESPA is maintained at the average level from 1991-2001. A series of 19 “sentinel wells” with a track record of groundwater level measurements are being utilized to measure progress

The groundwater users’ obligation to reduce water diversions by 240,000 acre-feet annually is being implemented on a local level by each of the participating districts represented by IGWA. Each district has been allocated a pro rata share of the 240,000 acre-feet based on the amount of water its members have diverted historically, and has developed and implemented its own plan for meeting its share of the reduction. A variety of tools are being employed, including pumping reductions, end gun removals, crop rotations, fallowing, conversion from groundwater to surface water irrigation, and recharge. Water right priorities among groundwater rights are being recognized by means of tiered reductions and assessments.

The stabilization and improvement of groundwater levels in the ESPA will not only augment water supplies of the SWC but will also secure a sustainable water supply for groundwater users, improve water supplies to the aquaculture industry, and reduce if not eliminate the risk of a breach of the minimum Snake River flows required under the Swan Falls Agreement.

Randy Budge and T.J. Budge are partners in the law firm of Racine Olson, and have served as the attorneys for IGWA for many years. They may be contacted at: (208) 232-6101,,

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