Gooding County Water Intelligence Brief

September 21, 2026 | Free-Tier Edition

Situation Summary

Snake River canal deliveries are entering the final weeks of the 2026 irrigation season, and ESPA spring discharge reflected in the Malad River near Gooding is running at 123 cfs and rising — a stable-to-positive signal for Hagerman Valley trout aquaculture operators heading into late September. Dairy operators and alfalfa producers should monitor delivery reliability closely as the season winds down, with the Big Wood River system contributing minimal late-season inflow given depleted snowpack in the Galena Summit headwaters. Reservoir storage data and 7-day forecast details are available in the full brief.

Snowpack Conditions

Both SNOTEL stations reporting for Gooding County's tributary watersheds show zero snow water equivalent as of September 20, consistent with normal seasonal conditions for this point in the calendar — median SWE at both stations is also 0.0" at this date.

Galena Summit (490:ID:SNTL): 0.0" SWE, 2.0" snow depth. The Galena Summit station monitors the Big Wood River headwaters in the Sawtooth Range — the primary local tributary snowpack indicator for Gooding County. The 2.0" depth reading at this date likely reflects early-season dusting rather than meaningful accumulation. The operational signal for water supply is the 2026 seasonal context: the Big Wood system melted out 4–6 weeks ahead of the historical median meltout date, meaning tributary inflows to the Snake near Gooding peaked well ahead of schedule and have since tapered. No meaningful snowmelt contribution to Big Wood River flows should be expected at this time.

Lewis Lake Divide: 0.0" SWE, 0.0" snow depth. This station shows a fully snow-free condition, consistent with normal late-September status.

Snowpack is not a current operational variable. The 2026 water year story for this watershed was written in March — both stations are now at their expected late-season baseline.

Streamflow Conditions

Malad River near Gooding (USGS 13152500): 123 cfs, rising — September 21.

This is the critical supply indicator for Gooding County's trout aquaculture sector. The Malad River near Gooding carries ESPA spring discharge from the Thousand Springs complex, where Eastern Snake Plain Aquifer groundwater emerges as massive springs from the Snake River canyon walls in the Hagerman Valley. Unlike snowmelt-driven rivers, Malad River flows reflect ESPA aquifer levels and spring discharge rates rather than seasonal precipitation — making this gauge relatively stable year-round and a reliable proxy for spring water availability to Hagerman Valley trout farms.

A reading of 123 cfs and rising is a stable-to-favorable signal for aquaculture operators. Trout farms hold separate IDWR spring water appropriations tied to this spring discharge system — not canal delivery schedules — and a rising trend at this gauge indicates no acute ESPA discharge stress at this time. Operators should nonetheless track this gauge through the fall transition, as multi-year ESPA aquifer trends can affect spring discharge rates independently of seasonal conditions.

For Snake River canal irrigators — dairy operators and alfalfa producers receiving surface water deliveries — the inherited Milner Dam and Twin Falls area gauges provide mainstem context. The Big Wood River tributary system is contributing minimally at this stage of the season given the early 2026 meltout.

Seasonal Guidance

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Data Sources: SNOTEL data through September 20, 2026; USGS streamflow data through September 21, 2026

Data Current As Of: September 21, 2026

Important Disclaimers: This brief provides automated analysis for informational purposes only. Specific numerical claims have not been independently verified. Consult official sources including your local water district, Idaho Department of Water Resources (IDWR — administers Water District 36 for middle Snake River and tributary water rights; also administers separate spring water appropriations for Hagerman Valley trout aquaculture and dairy operations), Idaho Department of Fish and Game (co-manages Thousand Springs State Park area), and U.S. Bureau of Reclamation, Pacific Northwest Region (Boise office) for regulatory decisions and water rights administration.