Cassia County Water Intelligence Brief

August 10, 2026 | Free-Tier Edition

Situation Summary

Cassia County's 2026 water season is defined by an extremely early snowmelt — SNOTEL stations serving both the Snake River corridor and Raft River Valley melted out 4–6 weeks ahead of the historical median meltout date, compressing the seasonal supply window. The Snake River corridor (Burley/Rupert area) is now fully dependent on upstream American Falls and Palisades reservoir carry-over storage and Eastern Snake Plain Aquifer (ESPA) groundwater to sustain late-season irrigation and processing industry demand through potato and beet harvest. Reservoir storage data and 7-day forecast details are available in the full brief.

Snowpack Conditions

All three SNOTEL stations serving Cassia County's water supply zone are reporting zero snowpack as of August 9, 2026 — consistent with normal seasonal conditions for this point in the calendar:

No percent-of-median figures are shown for any station, which indicates the August 9 median SWE is also 0.0" — these stations are at their normal end-of-summer condition. The operative 2026 signal is not current snowpack deficit but meltout timing: all three stations melted out approximately 4–6 weeks ahead of the historical median meltout date. That early departure accelerated peak runoff into May and June rather than June and July, reducing late-season streamflow and storage replenishment across both the Snake River corridor and Raft River Valley. No additional snowmelt-driven supply is available for the remainder of the season.

Streamflow Conditions

Snake River Corridor — Cassia Creek below Blacksmith Creek (USGS): Flowing at 4 cfs and rising as of August 10. Cassia Creek is a minor tributary indicator for the broader Snake River corridor system. Note that no active USGS gauge exists on the Snake River within Cassia County boundaries — the Snake River near Burley gauge (13085045) is discontinued. Supply assessment for the Burley Irrigation District service area relies on upstream indicators at Milner and Twin Falls rather than an in-county Snake River reading.

Raft River Valley — Raft River above Onemile Creek near Malta (USGS 13078000): Flowing at 2 cfs and falling as of August 10. This is the primary in-county streamflow indicator for the Raft River Valley ranching zone. At 2 cfs and declining, the Raft River is operating at the low end of its late-summer range — consistent with the early 2026 meltout reducing seasonal baseflow earlier than typical. Ranchers and irrigators in the Oakley, Malta, and Almo area dependent on Raft River surface water should treat current deliveries as at or near seasonal minimum. No meaningful streamflow recovery is expected without precipitation.

Seasonal Guidance

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

Data Sources: SNOTEL data through August 9, 2026; USGS streamflow data through August 10, 2026.

Data Current As Of: August 10, 2026.

Important Disclaimers: This brief provides automated analysis for informational purposes only. Specific numerical claims have not been independently verified. Consult official sources including Idaho Department of Water Resources (IDWR Water District 36, Burley office), Burley Irrigation District, U.S. Bureau of Reclamation Pacific Northwest Region (Boise office), and your local water district for regulatory decisions and water rights administration.