Sevier County Water Intelligence Brief

September 7, 2026 | Sevier River Basin

Situation Summary

Late-season streamflow across the Sevier River Basin is showing a split signal this week: the Sevier River at Hatch is rising at 47 cfs, while gauges at Kingston (8 cfs) and Lynndyl (22 cfs) are falling, and Manti Creek remains low at 3 cfs falling — a pattern indicating limited and uneven supply reaching irrigators across the county. Conditions point to continued tight late-season delivery reliability, and operators should plan accordingly as the irrigation season approaches its final weeks. Reservoir storage data and 7-day forecast details are available in the full brief.

Snowpack Conditions

Farnsworth Lake SNOTEL (09/06): 0.2" SWE | 1.0" snow depth

The Farnsworth Lake station is showing minimal residual snowpack, which is expected for early September — the historical median SWE for this date is effectively zero, so the station is at a normal seasonal condition for this point in the calendar. As background context, the 2026 season was defined by an anomalous March heat wave that drove meltout across Mountain West stations 4–6 weeks ahead of the historical median meltout date; that early release of snowmelt into the spring runoff window has shaped the entire downstream supply trajectory for the Sevier system this summer. No snowpack-driven late-season supplemental inflow should be expected at this time.

Streamflow Conditions

Sevier River at Hatch, UT: 47 cfs — rising

Sevier River near Kingston, UT: 8 cfs — falling

Sevier River near Lynndyl, UT: 22 cfs — falling

Manti Creek below Dugway Creek, nr Manti, UT: 3 cfs — falling

Sevier River near Sigurd, UT: No recent flow data available

The basin is showing notable variation across its length. The Hatch gauge — located in the upper Sevier corridor — is the lone rising signal at 47 cfs, suggesting localized inflow contribution in the upper basin, possibly from recent precipitation or tributary input. Downstream, the picture shifts: Kingston at 8 cfs falling represents a sharp reduction from Hatch, reflecting losses to diversions, channel transmission, and consumptive use as water moves through the mid-basin. Lynndyl at 22 cfs falling reflects the lower basin's late-season trajectory. The absence of recent data at the Sigurd gauge creates a meaningful monitoring gap in the mid-Sevier corridor and limits confidence in reach-by-reach delivery assessments for that area.

Manti Creek at 3 cfs and falling underscores the constrained tributary conditions entering the system from the Sanpete side. With no active gauge on the San Pitch River mainstem, Manti Creek remains the primary in-county USGS streamflow reference point — and its low, falling reading is consistent with late-season tributary recession across the broader basin.

Taken together, the dominant pattern is late-season decline across most of the system. Irrigators drawing from mid- and lower-basin points should treat current delivery availability as limited and potentially diminishing in the near term.

Seasonal Guidance

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Data Sources: SNOTEL data through September 6, 2026; USGS streamflow data through September 7, 2026

Data Current As Of: Utah Division of Water Rights

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, U.S. Bureau of Reclamation, and Utah Division of Water Rights for regulatory decisions and water rights administration.