Nelson Reservoir
Nelson Reservoir in Larimer County, Colorado is not rated for water quality — its monitoring record does not meet the evidence bar. Surface area: 40 acres.
- Area
- 40 acres
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Why Nelson Reservoir has no grade
We grade a lake only when the monitoring record supports a letter: at least three phosphorus or chlorophyll-a samples in the last ten years, scored against EPA National Lakes Assessment thresholds for this lake’s ecoregion. For Nelson Reservoir, no water-quality sampling on record for this lake.
Not Rated is not an F. It is EPA Integrated Reporting Category 3 — insufficient information. The water here may be excellent or poor; nobody has measured enough of it to say. Everything below that has been measured is still reported on this page.
Sampling is run by CDPHE and volunteer programs, and published through the EPA Water Quality Portal. Read the full grading methodology.
Nelson Reservoir is a 40-acre lake in Larimer County, Colorado.
Source: EPA Water Quality Portal sampling records, CDPHE, last sampled recent years. Grade methodology: LakeQuality methodology.
Watch Nelson Reservoir water quality
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Swimming Safety
Not ratedElevated nutrients
Not rated for swimming — there is not enough monitoring data to judge this lake
Water quality measurements for Nelson Reservoir
These readings exist but are not enough for an A–F grade — see why.
No clarity data. Trophic State Index: undefined.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | No recent samples | |
| Phosphorus | No recent samples | |
| Chlorophyll-a (Algae) | No recent samples | |
| Trophic State Index (TSI) |
Where to stay near Nelson Reservoir
Compare lakeside cabins, hotels, and vacation rentals near Nelson 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 Nelson Reservoir
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Lake Details
| Characteristic | Value |
|---|---|
| Surface Area | 40 acres |
No bathymetric survey has been published for Nelson Reservoir, so its depth is not documented here.
Fishing Nelson Reservoir
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Frequently asked questions about Nelson Reservoir
Where is Nelson Reservoir?
- Nelson Reservoir is a lake in Larimer County, Colorado. LakeQuality has not rated this lake (UNRATED) — no water-quality sampling on record for this lake.
What is the water quality grade for Nelson Reservoir?
- Nelson Reservoir in Larimer County, Colorado is not rated for water quality — its monitoring record does not meet the evidence bar. Surface area: 40 acres.
Is Nelson Reservoir safe to swim in?
- Not rated for swimming — there is not enough monitoring data to judge this lake. Nelson Reservoir is not rated for water quality — its monitoring record does not meet the evidence bar. Always check local health department advisories before swimming.
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Where this data comes from
Measurements for Nelson Reservoir come from the EPA Water Quality Portal. Per-sample source details are not recorded for this lake.