Salt Lake County Water Intelligence Brief

September 28, 2026 | Free Tier

Situation Summary

Jordan River flows at 1700 South are holding at 207 cfs and Little Cottonwood Creek is stable at 3 cfs — late-season conditions consistent with end-of-irrigation-season baseflow for the Jordan River Basin. For Salt Lake County's three municipal suppliers, the operational question now shifts from in-season delivery management to late-season storage accounting and early planning for fall system transitions. Reservoir storage data and 7-day forecast details are available in the full brief.

Snowpack Conditions

All five SNOTEL stations reporting in the Salt Lake County vicinity show end-of-season conditions, with snowpack at or near zero — normal for late September, when the historical median SWE at these dates is also 0.0".

| Station | SWE | Snow Depth |

|---|---|---|

| Atwater | 0.0" | 2.0" |

| Brighton | 0.1" | N/A |

| Dry Fork | 0.0" | 0.0" |

| Mill-D North | 0.0" | 1.0" |

| Snowbird | 0.3" | 0.0" |

Stations at 0.0" SWE represent normal seasonal condition for this point in the calendar — the median SWE for late September at these elevations is also 0.0", so no below-normal language is warranted based on current readings alone. The residual depth readings at Atwater (2.0") and Mill-D North (1.0") likely reflect early fresh precipitation or measurement artifact rather than retained seasonal snowpack.

2026 Seasonal Context: The operational story for 2026 is not the current snowpack reading but meltout timing. An anomalous March heat wave drove meltout across these stations approximately 4–6 weeks ahead of the historical median meltout date — compressing the spring runoff window and reducing late-season carry storage. That event is now background context; the downstream consequence is what matters for supply planning this fall.

Station Record Note: Atwater (SNOTEL 1308:UT:SNTL) has been reporting only since August 2022 — fewer than four full water years of record. For historical trend comparison, Brighton (reporting since 1986), Mill-D North (since 1988), and Snowbird (since 1989) carry substantially greater statistical weight and should be treated as the primary long-term indicators.

Streamflow Conditions

Two active USGS gauges are currently transmitting data within Salt Lake County.

Jordan River at 1700 South, Salt Lake City: 207 cfs, stable (09/28). This is the primary mainstem indicator for Jordan River Basin conditions. Late-September flows at this level are consistent with regulated late-season delivery — the Jordan River is heavily managed through diversions, return flows, and Utah Lake outflow regulation, meaning this reading reflects system operations as much as natural hydrology.

Little Cottonwood Creek at Jordan River near SLC: 3 cfs, stable (09/28). This represents typical late-season low-flow conditions on Little Cottonwood Creek following the end of primary snowmelt and irrigation demand season.

Data Gap Advisory: Big Cottonwood Creek (USGS 10168499, 10169000), Mill Creek (10170000), and Parleys Creek (10171500) are discontinued gauges not currently transmitting data. Users needing canyon-specific flow data for these drainages — which are critical to Salt Lake City Public Utilities canyon watershed operations — should contact Salt Lake City Public Utilities directly for current operational readings beyond what the two active gauges provide.

Seasonal Guidance

*For municipal managers, utility professionals, and policy stakeholders:*

*Secondary Section — Agricultural Users (South and West County)*

Agricultural users in Bluffdale, Herriman, Riverton, and Magna: Jordan River at 207 cfs and Little Cottonwood Creek at 3 cfs indicate late-season baseflow conditions. End-of-season field assessments and coordination with your water district on delivery wind-down schedules are appropriate at this stage. Contact Jordan Valley Water Conservancy District for delivery scheduling questions relevant to south county agricultural parcels.

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

Data Sources: SNOTEL data through September 27, 2026; USGS streamflow data through September 28, 2026.

Data Current As Of: September 28, 2026. Utah Division of Water Rights records current as of publication date.

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 Upper Colorado Region (for Deer Creek and Jordanelle reservoir operations), and Salt Lake City Public Utilities (canyon watershed storage) for regulatory decisions and water rights administration. This brief does not constitute legal, engineering, or water rights advice.