Minidoka County Water Intelligence Brief

June 22, 2026 | Free Tier

Situation Summary

The 2026 water year across the Snake River headwaters was defined by an anomalous March heat wave that drove snowpack meltout 4–6 weeks ahead of the historical median meltout date, compressing the spring runoff pulse earlier than normal and shifting the supply picture into a summer-management footing ahead of schedule. At Howells Ferry, the Snake River is currently delivering 8,530 cfs to the Minidoka Dam pool — the immediate upstream storage and diversion point for Minidoka Irrigation District deliveries across the county. Reservoir storage data for Lake Walcott and key upstream facilities, along with 7-day forecast details, are available in the full brief.

Snowpack Conditions

Galena Summit SNOTEL (as of June 21, 2026): Snow Water Equivalent 0.0", Snow Depth 0.0".

Galena Summit is fully melted out, which is the expected seasonal condition for late June — the median SWE for this date is also 0.0", so the station is reading at its normal late-season baseline. The meaningful 2026 signal is not today's reading but meltout timing: Galena Summit melted out 4–6 weeks ahead of the historical median meltout date, meaning the spring runoff contribution to Snake River storage and flows occurred significantly earlier in the season than normal. The snowpack-driven recharge window has closed. Minidoka County irrigators and Minidoka Irrigation District should treat remaining season supply as dependent on stored water in Lake Walcott and upstream reservoirs — not on any additional snowmelt contribution.

Streamflow Conditions

Snake River near Minidoka at Howells Ferry — USGS 13081500 (as of June 22, 2026): 8,530 cfs, stable.

The Howells Ferry gauge is the defining upstream supply signal for Minidoka County — it measures what the Snake River is delivering to the Minidoka Dam pool before any Magic Valley diversions downstream. At 8,530 cfs with a stable trend, flows are in a mid-to-late season range. This gauge drains approximately 15,700 square miles of upper Snake River basin, and its readings serve as a leading indicator for conditions that will propagate downstream through Milner Dam and into the Twin Falls, Jerome, and Cassia county delivery systems. The stability of current flows is operationally relevant for Minidoka Irrigation District diversion planning, though the early meltout year means the high-flow runoff peak has already passed. Minidoka County users — sitting upstream of Milner — are seeing these conditions earlier in the supply chain than downstream counties.

Seasonal Guidance

Subscribe for the full brief including reservoir storage, weather forecasts, depletion analysis, and detailed operational recommendations.

Data Sources: SNOTEL data through June 21, 2026; USGS streamflow data through June 22, 2026.

Data Current As Of: June 22, 2026. Idaho Department of Water Resources Eastern Regional Office, Pocatello: (208) 525-7161.

Important Disclaimers: This brief provides automated analysis for informational purposes only. Specific numerical claims have not been independently verified. Consult official sources including Minidoka Irrigation District (primary delivery entity for Minidoka Dam diversions), U.S. Bureau of Reclamation Pacific Northwest Region — Boise office (operates Minidoka Dam and Lake Walcott under the Minidoka Project), Idaho Department of Water Resources (administers Water District 36, middle Snake River), and USBR for American Falls Reservoir and Palisades Reservoir upstream context before making operational or regulatory decisions. This brief does not constitute water rights advice.