Douglas Reservoir
Larimer County, Colorado565 acresView mapDirections
Colorado WQCD publishes the water-quality measurements for Douglas Reservoir. Here is what has been measured.
- Mesotrophic
- 16 ft max depth
- Public access
- Limited data
Douglas Reservoir in Larimer County, Colorado has water-quality measurements published by Colorado WQCD, shown here as reported. Water clarity: 4.1 ft visibility. Phosphorus: 11 µg/L. Chlorophyll-a (algae): 2.5 µg/L. Surface area: 565 acres.
Douglas Reservoir is a 565-acre mesotrophic lake in Larimer County, Colorado with an estimated average depth of about 16 feet. Limited fish-species data available. Public access is available with 1 public boat landing. Compared to the 8 other monitored lakes in Larimer County, Douglas Reservoir ranks #3 for water quality.
Source: EPA Water Quality Portal sampling records, CDPHE, last sampled 2021-09-08. Methodology: how these readings are compared.
Douglas Reservoir covers about 570 acres in Larimer County. It has one public boat landing. Vrbo is where to look for cabins and lake homes around Douglas Reservoir, and Booking.com and Expedia search hotels near the lake for your dates.
What Douglas Reservoir is good for
From access and monitoring records, not editorial picks.
- Boat launch1 documented ramp
Swimming conditions
Readings onlyLimited data
Based on clarity and algae readings from past sampling — there is no live water temperature and a current cyanobacteria reading for this lake. Check your state or county health department before you swim.
Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.
Whether Douglas Reservoir is safe to swim in today is a call for the Water Quality Control Division of the Colorado Department of Public Health and Environment and the county health department, who post current advisories. LakeQuality does not issue swimming clearances.
Water quality measurements for Douglas Reservoir
These are the measurements Colorado WQCD publishes for Douglas Reservoir, shown as reported. The condition class beside each reading is the EPA National Lakes Assessment class for this lake’s ecoregion.
Murky, only visible to about 4.1 ft. Phosphorus 11 µg/L. Chlorophyll-a 2.5 µg/L. TSI 45.
| Measure | Reading | Where it sits |
|---|---|---|
| Water clarity (Secchi depth) | 4.1ft | Measured, not scored How deep a black-and-white disk stays visible from the surface. Higher is clearer. |
| Total phosphorus | 11µg/L | Good GoodFairPoor |
| Chlorophyll-a (algae) | 2.5µg/L | Good GoodFairPoor |
| Trophic state (TSI)Carlson's 0–100 index of how much algae a lake can support, from clarity, phosphorus and chlorophyll-a. | 45 | Mesotrophic OligotrophicMesotrophicEutrophicHypereutrophic |
Moderate nutrients, good water quality
Ask about Douglas Reservoir
Answers come straight from the public measurements and survey records on this page.
Lake Details
Max depth
~16 ft est.
Surface area
565 acres
Public access
Yes
Listed by Colorado WQCD
Depth marked “est.” is a modeled maximum from GLOBathy (Khazaei et al. 2022, CC0), not a measured survey. Colorado has not published bathymetry for Douglas Reservoir.
Lake Size & Watershed
Watershed (drainage) area
44 sq mi
HydroLAKES / HydroSHEDS
Shoreline
4 mi
HydroLAKES / HydroSHEDS
Elevation
5,203 ft
Size, shoreline, and watershed area from HydroLAKES (HydroSHEDS). Mean depth here is modelled, not surveyed — HydroLAKES v1.0 estimates lake depth from surrounding terrain rather than from soundings. Treat it as an approximation, and prefer a state bathymetric survey where one exists.
Recreation & Access
- Douglas Reservoir State Wildlife AreaPublic
Named access points in the USGS National Boat Ramps inventory, within about 3 miles. More lakes with boat ramps
Stays via Stay22
Stays near Douglas Reservoir
Compare lakeside cabins, hotels, and vacation rentals near Douglas Reservoir in Larimer County, Colorado — live availability and prices for your trip. Switch the map to Satellite to see the lake and how close each stay is to the water.
Top-rated places to stay near Douglas Reservoir
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Fishing Douglas Reservoir
Reservoir Info (USACE NID)
Douglas Reservoir is a man-made reservoir impounded by the Douglas (completed 1901), built primarily for irrigation on the Dry Creek; earth-type dam, 47 ft tall and 3,700 ft long.
- Surface area
- 565 ac
- Normal storage
- 8,940 ac-ft
- Max storage
- 13,324 ac-ft
- Drainage area
- 43 sq mi
- Hazard class
- High
- Owner
- WRCC, INC. (NELSON, KIMBERLY)
All listed purposes: Irrigation;Fish and Wildlife Pond.
Source: USACE National Inventory of Dams, NID ID CO01163 · Operator website
Nearby Lakes in Larimer County
Frequently asked questions about Douglas Reservoir
Where is Douglas Reservoir?
- Douglas Reservoir is a lake in Larimer County, Colorado. Its water-quality measurements are published by Colorado WQCD and shown on this page as reported.
What is the water quality of Douglas Reservoir?
- Douglas Reservoir in Larimer County, Colorado has water-quality measurements published by Colorado WQCD, shown here as reported. Water clarity: 4.1 ft visibility. Phosphorus: 11 µg/L. Chlorophyll-a (algae): 2.5 µg/L. Surface area: 565 acres.
Is Douglas Reservoir safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.
How deep is Douglas Reservoir?
- No published bathymetric survey covers Douglas Reservoir, so its depth has not been measured. The HydroLAKES global model estimates an average depth of about 16 feet, but that is a modelled estimate derived from surrounding terrain rather than a measurement on the water, so treat it as approximate. The lake covers 565 acres.
Are there boat ramps on Douglas Reservoir?
- Douglas Reservoir has 1 documented boat landing in the USGS National Boat Ramps inventory. Named access points include Douglas Reservoir State Wildlife Area. Public access is listed as yes.
Can I fish at Douglas Reservoir?
- Douglas Reservoir has 1 documented boat landing in the USGS National Boat Ramps inventory. Seasons, size and bag limits, and whether you need a license are set by Colorado's fish and wildlife agency, so check its current regulations before you go.
Explore Douglas Reservoir across LakeQuality
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Where this data comes from
16 measurements from 2 monitoring stations, 2021. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- Colorado Dept. of Public Health & Environment-WQCD
21COL001_WQX16 samples · 2021
Analytical methods
- Secchi disk depth measurement
- Phosphorus by Colorimetry
- 10200 H ~ Chlorophyll a-b-c Determination
- Nitrogen in Water by Pyrolysis Detection
Monitoring station identifiers (2)
EPA condition classes from the National Lakes Assessment (EPA 841-R-24-006, Table 6-3), applied by ecoregion. See where the data comes from and data sources.
Other records on this page
Lake size & watershed from HydroLAKES (HydroSHEDS)
Named boat-access points from the USGS National Boat Ramps inventory