Larimer County Water Intelligence Brief

October 19, 2026 | Cache la Poudre & Big Thompson Corridors

Situation Summary

Both river systems are running at late-season low flows this week, with the Big Thompson at Loveland reporting 4 cfs (falling) and the Cache la Poudre gauges showing 14–29 cfs across the Fort Collins and Timnath reaches — conditions consistent with the end of the irrigation season and declining in-county delivery pressure. For alfalfa, hay, and cattle operations along both corridors, this week's flows reflect normal seasonal wind-down rather than an acute supply emergency, though the Big Thompson's falling trend warrants attention for any remaining active diversions. Reservoir storage data for Horsetooth Reservoir and Carter Lake, along with 7-day forecast details, are available in the full brief.

Snowpack Conditions

The five SNOTEL stations monitoring Larimer County's headwaters — spanning both the Big Thompson and Cache la Poudre watersheds — show minimal to trace snowpack accumulation as of October 18, consistent with early-season baseline conditions.

Big Thompson headwaters (Rocky Mountain National Park corridor):

Cache la Poudre headwaters:

Where percent-of-median figures are available, readings range from 66% to 100% of median — broadly near-normal for this point in the calendar. Bear Lake and Hourglass Lake show no reportable depth, which is expected at this date. The relevant 2026 snowpack story is not current SWE but meltout timing: across these stations, snowpack melted out approximately 4–6 weeks ahead of the historical median meltout date due to an anomalous March heat wave. That early meltout shaped the summer delivery season and is background context for evaluating late-season reservoir carry-in.

Streamflow Conditions

Three active USGS gauges cover Larimer County's two river systems.

Big Thompson River:

This gauge captures combined native Big Thompson flow and any C-BT releases through the Olympus Dam system. At 4 cfs and falling, the Big Thompson is at minimal late-season flow. Irrigators with active diversions on the Loveland agricultural reach should confirm delivery viability with their ditch company this week.

Cache la Poudre River:

The Fort Collins gauge is physically within the city's urban corridor, where municipal return flows from Fort Collins Utilities augment the agricultural supply downstream — the rising trend at this gauge likely reflects that urban-agricultural interface dynamic. The Timnath gauge, further downstream near the Larimer/Weld County line, reads 14 cfs stable, showing the expected downstream attenuation after upstream diversions. The Cache la Poudre holds Colorado's only federally designated Wild and Scenic River corridor, a constraint that shapes long-term supply infrastructure on this system.

Seasonal Guidance

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

Data Sources: SNOTEL data through October 18, 2026; USGS streamflow data through October 19, 2026

Data Current As Of: October 19, 2026. 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, and Colorado Division of Water Resources Water Division 1 (Greeley office) for regulatory decisions and water rights administration.