Cassia County Water Intelligence Brief

August 3, 2026 | Free-Tier Edition

Situation Summary

Cassia County enters the critical late-season irrigation window with snowpack entirely absent across all monitored elevations — consistent with an exceptionally early 2026 meltout that ran 4–6 weeks ahead of historical median meltout dates across the region. Both the Snake River corridor (Burley/Rupert area) and the Raft River Valley (Oakley/Malta area) are operating on stored and residual runoff with no remaining snowmelt contribution, placing elevated importance on upstream reservoir position and groundwater availability for the remainder of the season. Reservoir storage data and 7-day forecast details are available in the full brief.

Snowpack Conditions

All three SNOTEL stations reporting for Cassia County's contributing mountain terrain show zero snow water equivalent and zero snow depth as of August 2, 2026:

No percent-of-median figures are shown for any station, which reflects that the historical median SWE for this calendar date is also 0.0" — these stations are at their normal seasonal condition for early August. The significant 2026 story is not current snowpack deficiency but meltout timing: all three stations melted out 4–6 weeks ahead of the historical median meltout date, meaning the seasonal runoff pulse that recharges Snake River flows and ESPA groundwater arrived substantially earlier than normal. That early pulse has now fully passed. No additional snowmelt contribution to Snake River corridor deliveries or Raft River Valley streamflow should be expected for the remainder of the 2026 irrigation season.

Streamflow Conditions

Snake River Corridor indicator — Cassia Creek below Blacksmith Creek (USGS): Recorded at 4 cfs and falling as of August 3. This small tributary reflects late-season recession conditions typical of early August, with no snowmelt input remaining. Note: No active USGS Snake River gauge exists 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 reference points outside county boundaries. Burley Irrigation District delivery status is the operational indicator for Snake River corridor irrigators and processing industry users.

Raft River Valley indicator — Raft River above Onemile Creek near Malta (USGS 13078000): Recorded at 3 cfs and stable as of August 3. This is the primary in-county streamflow indicator for southern Cassia County ranching and limited irrigation operations. At 3 cfs, the Raft River is operating at the lower end of its late-season range — sufficient context for Oakley and Malta area ranchers to assess livestock watering and any remaining irrigation draw. Cassia Creek at 4 cfs (falling) and Raft River at 3 cfs (stable) together confirm that both surface water systems serving the county's distinct agricultural zones are in late-season low-flow conditions with no recovery signal on the horizon.

Seasonal Guidance

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

Data Sources: SNOTEL data through August 2, 2026; USGS streamflow data through August 3, 2026

Data Current As Of: August 3, 2026. SNOTEL data from NRCS National Water and Climate Center. Streamflow data from USGS National Water Information System.

Important Disclaimers: This brief provides automated analysis for informational purposes only. Specific numerical claims have not been independently verified. Consult official sources for regulatory decisions and water rights administration, including: Idaho Department of Water Resources (IDWR), Water District 36, Burley district office; Burley Irrigation District; U.S. Bureau of Reclamation, Pacific Northwest Region (Boise office), for American Falls Reservoir and Palisades Reservoir upstream storage context; and IDWR Eastern Regional Office (Pocatello, (208) 525-7161) for Raft River Valley water right administration.