Water Intelligence Brief · Archive

Larimer County, CO

June 22, 2026

Larimer County Water Intelligence Brief

Free-Tier Edition | June 22, 2026

*Cache la Poudre & Big Thompson Corridors | C-BT System | Water Division 1*

Situation Summary

Both the Cache la Poudre and Big Thompson watersheds have completed their snowmelt runoff seasons well ahead of the historical norm, with SNOTEL stations across Larimer County's headwaters melting out 4–6 weeks earlier than the historical median meltout date following an anomalous March heat wave. Streamflows on both rivers are measurable but modest for late June, reflecting that the main pulse of runoff has already passed through the system. Reservoir storage data for Horsetooth Reservoir and Carter Lake, along with 7-day forecast details and depletion analysis, are available in the full brief.

Snowpack Conditions

All five SNOTEL stations monitoring Larimer County's two river systems have reached seasonal meltout. The key framing for 2026 is not current SWE deficits — it is timing: meltout occurred 4–6 weeks earlier than the historical median meltout date across both the Big Thompson and Cache la Poudre headwaters.

Big Thompson Headwaters (Rocky Mountain National Park corridor):

Bear Lake (9,490 ft): SWE 0.0", snow depth 0.0" as of June 21. Fully melted out. Bear Lake monitors the lower Big Thompson headwater zone and is a primary indicator for C-BT delivery corridor snowpack.

Willow Park (10,710 ft): SWE 0.3", snow depth 0.0" as of June 21. The only station in the network retaining any measurable water equivalent, though at trace levels and with no snow depth remaining. Willow Park sits at the highest elevation of the five in-county stations — its residual 0.3" SWE is not operationally significant as a late-season supply source but confirms the upper Big Thompson drainage is functionally melted out.

Cache la Poudre Headwaters:

Joe Wright (elev. approx. 10,000 ft): SWE 0.1", snow depth 2.0" as of June 21. The only station showing measurable snow depth, though the low SWE-to-depth ratio indicates the snowpack is dense, settled, and in advanced melt. Joe Wright monitors the upper Poudre drainage and is a key indicator for early-season Poudre flows.

Deadman Hill: SWE 0.0", snow depth 0.0" as of June 21. Fully melted out.

Hourglass Lake: SWE 0.0", snow depth 0.0" as of June 21. Fully melted out.

Integrated Snowpack Signal: When no percent-of-median figure is reported alongside a 0.0" SWE reading, it indicates the historical median SWE for that date is also 0.0" — meaning these stations are at their normal seasonal condition for late June, not anomalously below normal today. The significant 2026 story is that this fully-melted condition was reached roughly 4–6 weeks earlier than typical, compressing the runoff window and accelerating the transition to a storage-dependent supply regime for both river systems.

Streamflow Conditions

Both the Cache la Poudre and Big Thompson rivers are carrying measurable flows, but directional trends differ and warrant close attention from canal operators and irrigators on both corridors.

Big Thompson River:

Big Thompson River at Loveland (06741510): 88 cfs, rising, as of June 22. This gauge captures combined native Big Thompson flows and any C-BT releases passing through Olympus Dam into the Loveland agricultural reach. The rising trend at Loveland is a notable operational signal — users should confirm with Northern Water whether the rise reflects managed C-BT releases from the Lake Estes/Olympus system or late-melting high-elevation contributions.

Cache la Poudre River:

Cache la Poudre at Fort Collins (06752260): 60 cfs, falling, as of June 22. This in-county gauge on Colorado's only federally designated Wild and Scenic River reflects conditions above the primary Fort Collins municipal diversion points. Falling flows here indicate the main runoff pulse has passed and supply is transitioning to base flow conditions.

Cache la Poudre above Boxelder Creek near Timnath (06752280): 50 cfs, falling, as of June 22. The Timnath gauge sits downstream of Fort Collins municipal diversions and urban return flows, near the Larimer/Weld County line. The 10 cfs differential between Fort Collins and Timnath reflects net diversions and return flows through the Fort Collins urban reach — an important interface for downstream agricultural users on both sides of the county line. Falling trend confirms the Poudre corridor is in post-peak recession.

Operational Context: Falling Poudre flows and an early meltout signal that Poudre direct-flow water rights holders — particularly junior priority holders — should expect delivery conditions to tighten as summer progresses. Big Thompson users should monitor Northern Water communications regarding C-BT release scheduling from Horsetooth and Carter Lake as the primary remaining source of managed supply through the season.

Seasonal Guidance

Contact Northern Water (northernwater.org, Berthoud office) to verify current C-BT unit year allotment status, Horsetooth Reservoir and Carter Lake storage levels, and C-BT release scheduling for both the Big Thompson and Poudre delivery corridors.

Check with the Colorado Division of Water Resources, Water Division 1 (Greeley office) regarding current priority administration on the Cache la Poudre and Big Thompson rivers and any augmentation plan obligations applicable to your operation.

Canal company members should contact their board or ditch rider — including Water Supply and Storage Company, North Poudre Irrigation Company, and Larimer County Canal No. 2 — for current headgate delivery schedules and any anticipated pro-rata reductions on the Poudre corridor.

City of Fort Collins Utilities can provide information relevant to municipal diversion activity and return flow timing on the lower Poudre reach, which affects available flows for downstream agricultural users.

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

Data Sources: SNOTEL data through June 21, 2026; USGS streamflow data through June 22, 2026

Data Current As Of: June 22, 2026; administrative context reflects Colorado Division of Water Resources records

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. This brief does not constitute legal, engineering, or water rights advice.

Data & Disclaimers

Sources: NRCS SNOTEL network · USGS National Water Information System · National Weather Service

This brief provides automated analysis for informational purposes only. Consult official sources including your local water district and state Division of Water Rights for regulatory decisions. This document does not constitute legal, regulatory, or engineering advice.

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