Windsor Lake
Weld County, Colorado197 acresView mapDirections
Nutrients and algae run above the regional average.
↑ up from F at the last regrade
- Eutrophic
- #1 of 5 in the county
- 11 ft max depth
- Limited data
Windsor Lake in Weld County, Colorado has a water quality grade of D (Nutrient-rich). Water clarity: 2 ft visibility. Phosphorus: 140 µg/L. Chlorophyll-a (algae): 25.4 µg/L. Surface area: 197 acres.
- Clarity
- 2 ft
- Max depth
- ~11 ft est.
- Area
- 197 acres
- Type
- Eutrophic
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Stays near Windsor Lake
Compare lakeside cabins, hotels, and vacation rentals near Windsor Lake in Weld 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. The water-quality grade measures nutrients and algae, not lodging — cabins and rentals around Windsor Lake are listed below.
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Windsor Lake is a 197-acre productive, nutrient-rich eutrophic lake in Weld County, Colorado with an estimated average depth of about 11 feet. Water quality is graded D based on 3 sampling years through 2020. Compared to the 4 other monitored lakes in Weld County, Windsor Lake ranks #1 for water quality.
Source: EPA Water Quality Portal sampling records, CDPHE, last sampled 2020-09-02. Grade methodology: LakeQuality methodology.
Swimming Safety
Grade onlyLimited data
Based on clarity and algae grades from past sampling — we do not hold live water temperature and a current cyanobacteria reading for this lake. Check your state or county health department before you swim.
The D is nutrients and algae, not a swimming clearance. Check local advisories before you swim.
Water Quality Grade: D (Nutrient-rich)
Very murky, less than 2 ft of visibility. Phosphorus 140 µg/L. Chlorophyll-a 25.4 µg/L. TSI 68. The letter is not a swimming clearance.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 2 ft | Not graded |
| Phosphorus | 140 µg/L | Poor |
| Chlorophyll-a (Algae) | 25.4 µg/L | Poor |
| Trophic State Index (TSI) | 68 | Eutrophic |
High nutrients, frequent algae, reduced clarity
Lake Details
| Characteristic | Value |
|---|---|
| Maximum Depth | ~11 ft est. |
| Average Depth | ~7 ft est. |
| Surface Area | 197 acres |
Depth marked “est.” is a modeled maximum from GLOBathy (Khazaei et al. 2022, CC0), not a measured survey. Colorado has not published bathymetry for Windsor Lake.
Lake Size & Watershed
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.
Fishing Windsor Lake
Reservoir Info (USACE NID)
Windsor Lake is a man-made reservoir impounded by the Windsor Lake (completed 1904), built primarily for irrigation on the Cache La Poudre River-Os; earth-type dam, 11 ft tall and 2,250 ft long.
- Surface area
- 197 ac
- Normal storage
- 3,008 ac-ft
- Max storage
- 3,990 ac-ft
- Drainage area
- 4 sq mi
- Hazard class
- High
- Owner
- KERN RESERVOIR AND DITCH CO (WAGNER, DENNIS)
All listed purposes: Irrigation;Recreation.
Source: USACE National Inventory of Dams, NID ID CO00854 · Operator website
County Ranking
Ranked #1 of 5 lakes in Weld County
Nearby Lakes in Weld County
Frequently asked questions about Windsor Lake
Where is Windsor Lake?
- Windsor Lake is a lake in Weld County, Colorado. LakeQuality grades it D for nutrients and algae. The letter is not a swimming clearance.
What is the water quality grade for Windsor Lake?
- Windsor Lake in Weld County, Colorado has a water quality grade of D (Nutrient-rich). Water clarity: 2 ft visibility. Phosphorus: 140 µg/L. Chlorophyll-a (algae): 25.4 µg/L. Surface area: 197 acres.
Is Windsor Lake safe to swim in?
- The D is nutrients and algae, not a swimming clearance. Check local advisories before you swim.
How deep is Windsor Lake?
- No published bathymetric survey covers Windsor Lake, so its depth has not been measured. The HydroLAKES global model estimates an average depth of about 11 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 197 acres.
Explore Windsor Lake across LakeQuality
11.8 mi away · cable-pulled, no boat wake
Species activity outlook by water temperature and season
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High nutrients, frequent algae, reduced clarity
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Where this data comes from
16 measurements from 2 monitoring stations, 2020. 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 · 2020
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)
Grade thresholds from the EPA National Lakes Assessment (EPA 841-R-24-006, Table 6-3), applied by ecoregion. See how grades are calculated and data sources.
Other records on this page
Lake size & watershed from HydroLAKES (HydroSHEDS)