Larimer County Water Intelligence Brief

Free-Tier Edition | July 13, 2026

Situation Summary

Larimer County's two-river system — the Cache la Poudre and Big Thompson — is operating under mid-July low-flow conditions consistent with a year in which mountain snowpack melted out approximately 4–6 weeks ahead of the historical median meltout date across all monitored headwater stations. In-county storage at Horsetooth Reservoir and Carter Lake represents the primary supply buffer for C-BT allotment holders and canal company members as both rivers run well below peak seasonal levels. Reservoir storage data, 7-day forecast details, and C-BT unit value analysis are available in the full brief.

Snowpack Conditions

All five SNOTEL stations monitoring Larimer County's headwaters have completed seasonal meltout, consistent with the anomalous early-melt pattern documented across the Mountain West in 2026.

Big Thompson Headwaters (Rocky Mountain National Park corridor):

These two stations are the primary headwater indicators for the Big Thompson delivery corridor and the C-BT system's native-flow component. Their meltout status confirms that snowmelt-driven inflow to Lake Estes and the Big Thompson reach has largely concluded for the season.

Cache la Poudre Headwaters:

Joe Wright's 0.1" SWE is the sole remaining snowpack signal across all five stations and represents a negligible contribution to Poudre streamflow at this stage of the season. The Poudre headwater network as a whole is at seasonal meltout. Across both river systems, the 2026 meltout occurred 4–6 weeks ahead of the historical median meltout date — meaning the spring snowmelt pulse that typically supports early-summer streamflow and reservoir filling concluded well before historical norms.

Streamflow Conditions

Both river systems are reflecting post-snowmelt, mid-summer baseflow conditions. Readings are from July 13, 2026.

Big Thompson River:

At 68 cfs, the Big Thompson at Loveland is running under stable conditions. This gauge captures combined native Big Thompson flow and any C-BT releases through the Olympus Dam system, making it the primary operational indicator for Big Thompson corridor irrigators in the Loveland agricultural reach. Stability at this level indicates no active surge contribution from remaining snowmelt and reflects the system settling into summer baseflow.

Cache la Poudre River:

The Poudre is running at notably low levels at both in-county gauges. The Fort Collins gauge at 10 cfs and the Timnath gauge at 4 cfs reflect the post-snowmelt transition to summer baseflow on Colorado's only federally designated Wild and Scenic River. The rising trend at both stations warrants monitoring — possible contributors include localized convective storm runoff or shifts in upstream diversion activity, though no causal data is available in this tier. Fort Collins municipal return flows represent a meaningful component of late-summer Poudre flows in the lower corridor, a feature that partially supplements agricultural supply downstream of the city's diversions. Senior water rights on the Poudre date to the 1860s–1870s; at 4–10 cfs, the river has limited capacity to serve all decreed rights simultaneously, and Water Division 1 administration of the lower Poudre is directly relevant to canal company operations in this reach.

Seasonal Guidance

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Data Sources: SNOTEL data through July 12, 2026; USGS streamflow data through July 13, 2026

Data Current As Of: Colorado Division of Water Resources

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, Northern Colorado Water Conservancy District (Northern Water — headquartered in Berthoud, Larimer County; administers C-BT Project; Horsetooth Reservoir and Carter Lake data via northernwater.org or USBR HydroMet site HRT), City of Fort Collins Utilities (municipal Poudre diversions), and Colorado Division of Water Resources Water Division 1 (Greeley office) for regulatory decisions and water rights administration.