NOTICE OF MITIGATION PLAN SUBMITTED BY THE UPPER BIG LOST RIVER GROUND WATER DISTRICT IN RESPONSE TO THE SURFACE WATER COALITION WATER DELIVERY CALL Notice is hereby given that on February 17, 2026, the Upper Big Lost River Ground Water District ("UBLRGWD"), through their Board Chairman, Randy Nelson, P.O. Box 122, Mackay, Idaho 83251, submitted the Upper Big Lost River Ground Water District's Mitigation Plan ("UBLRGWD Plan") to the Idaho Department of Water Resources ("Department") pursuant to Rule 43 of the Department's Rules for Conjunctive Management of Surface and Ground Water Resources (CM Rules). The UBLRGWD Plan is intended to satisfy UBLRGWD's mitigation obligation for the Surface Water Coalition ("SWC") Water Delivery Call administered by the Department and watermasters of state water districts who administer ground water rights within the Eastern Snake Plain Aquifer Area of Common Ground Water Supply ("ESPA ACGWS"). The SWC consists of irrigation water delivery entities with senior surface water rights diverted from the Snake River above Milner Dam. The SWC members include A&B Irrigation District, American Falls Reservoir District #2, Burley Irrigation District, Milner Irrigation District, Minidoka Irrigation District, North Side Canal Company, and Twin Falls Canal Company. Patrons of BLRGWD divert ground water from wells primarily for agricultural irrigation within the Big Lost River tributary basin and hold ground water rights within the ESPA ACGWS that are junior in priority to the SWC's senior priority Snake River water rights. UBLRGWD proposes three ways to mitigate injury to the SWC members. First, UBLRGWD proposes reducing district groundwater diversions by 11.4%. UBLRGWD Plan, at 3. The 11.4% reflects "the average pumping reduction required of signatory ground water districts" in the CM-MP-2024-003 plan. Id. UBLRGWD intends to use district ground water diversion amounts from 2013–2015 as its calculated baseline for reduction. Id. Currently, under the proposed plan, UBLRGWD's annual reduction obligation would be 1077.2 acre-feet. Id. Second, UBLRGWD proposes providing the SWC with 231+/- acre feet of storage water or $16,170 annually, to be used by the SWC for the leasing of storage water. Finally, the UBLRGWD proposes performing ground water recharge within Water District 34. Id., at 3. UBLRGWD proposes to perform ground water recharge within Water District 34, receiving a 12.2% or 1:1 credit for each acre-foot of recharge that occurs within the Big Lost River Tributary. Id. at 2. UBLRGWD also proposes that in the event of a reasonable carryover shortfall, "any unused pumping volume or recharge credit during an annual season maybe used as credit toward carryover shortfall in whole or part." Id. The Department will process the UBLRGWD Plan under the Department's CM Rules (IDAPA 37.03.11). A complete copy of the UBLRGWD Plan is available for review at the following website link: https://idwr.idaho.gov/legal-actions/mitigation-plan-actions/swc/ublrgwd/. This notice does not represent analysis or approval of the proposed plan by the Department. Protests against approval of the UBLRGWD Plan must be filed with the Department, together with a protest fee of $25, on or before 3/23/2026. Rule 53 of the Department's Rules of Procedure (IDAPA 37.01.01.053) outlines how documents may be filed with the Department and when they are considered filed. A copy of the Rules of Procedure may be obtained at the following website link: https://adminrules.idaho.gov/rules/current/37/370101.pdf. The protest must include a certificate of service showing that a copy of the protest has been mailed or delivered personally to UBLRGWD. Mathew Weaver, Director. IPL0317972 Mar 4,11 2026