Water Resource Board lists projects, ARPA spending and recharge capacity as part of statewide water strategy

Jeff Rebold, chairman of the Idaho Water Resource Board, told the House Resources and Conservation Committee the board has overseen roughly $575 million in appropriations since 2019 and is using those funds for a mix of regional projects, aging‑infrastructure grants and recharge initiatives.

Rebold said the board’s water management account and ARPA allocations have supported a wide range of projects: Anderson Ranch Dam raise, the Mountain Home Air Force Base pipeline, American Falls Dam spillway repair, ESPA recharge infrastructure, the New York Canal rehabilitation and dozens of aging‑infrastructure grants across the state. He described a competitive aging‑infrastructure grant program that reimburses up to one‑third of project costs (with a $2 million cap per project) and a separate groundwater‑to‑surface‑water conversion grant program that can cover up to 50% of project costs (caps described in the committee briefing).

The board pointed to telemetry and monitoring grants to help irrigators install measurement and reporting equipment; Rebold said the telemetry program provides up to 50% of eligible costs, capped at $250,000, and that applications were due March 28. He described a flood‑management grants program that covers up to 50% of eligible costs (capped at $200,000) and the board’s regional water sustainability projects, which fund larger basin‑scale work.

Rebold discussed ESPA recharge work and capacity. He said the board has built recharge capacity and operates sites that can capture varying volumes depending on annual runoff; board materials shown to the committee reported roughly 2,000 cubic feet per second of total lower‑valley capacity and nearly 600 cfs in the upper valley, and Rebold said the board needs substantially more upper‑valley capacity to reliably capture high‑runoff years. The board also described a cloud‑seeding partnership with Idaho Power and local water users that the board supports; the board presented an average annual program budget of about $3.6 million and an estimated program cost of roughly $3.77 per acre‑foot for additional runoff generated, according to the slides Rebold showed.

On larger surface‑storage work, Rebold updated committee members on the Anderson Ranch dam raise under the WIN Act. He said a six‑foot raise would add about 29,000 acre‑feet of storage; the board’s current estimate places the project cost at roughly $126 million, with about 11% federal cost share, and construction contracts projected in the 2026 time frame.

Rebold also described the Mountain Home Air Force Base resiliency project (state responsibility for a transmission pipeline estimated at roughly $40 million, expected to be ready for delivery in 2025) and earlier‑completed work such as modifications to the Priest Lake outlet and New York Canal rehabilitation planning driven by safety concerns. He said the board has awarded multiple rounds of grants for aging infrastructure and has funded pilot projects and larger conversions intended to reduce stress on aquifers.

Lawmakers asked about incidental recharge lost when canals are lined. Rebold said the board weighs safety and infrastructure risk against incidental recharge losses; he described an anticipated incidental‑recharge loss of roughly 25,000–30,000 acre‑feet per year for the New York Canal lining project but said the board is studying recharge alternatives in the Treasure Valley and intends pilot recharge projects and compensatory measures in other parts of the valley.

Rebold said the board’s work seeks a practical balance: capturing more of the millions of acre‑feet that pass Milner in wet years without overbuilding infrastructure that would be rarely used. The board described an average of roughly 1.7 million acre‑feet passing Milner annually (with large interannual variation) and said it is studying the optimal level of investment to capture enough water in high‑runoff years to stabilize aquifers.