McGrew Reservoir
McGrew Reservoir in Weld County, Colorado is not rated for water quality — its monitoring record does not meet the evidence bar. Surface area: 116 acres.
- Area
- 116 acres
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Why McGrew 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 McGrew 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.
McGrew Reservoir is a 116-acre lake in Weld County, Colorado.
Source: EPA Water Quality Portal sampling records, CDPHE, last sampled recent years. Grade methodology: LakeQuality methodology.
Watch McGrew 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 McGrew 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 McGrew Reservoir
Compare lakeside cabins, hotels, and vacation rentals near McGrew Reservoir 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.
Top-rated places to stay near McGrew Reservoir
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Lake Details
| Characteristic | Value |
|---|---|
| Surface Area | 116 acres |
No bathymetric survey has been published for McGrew Reservoir, so its depth is not documented here.
Fishing McGrew Reservoir
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Frequently asked questions about McGrew Reservoir
Where is McGrew Reservoir?
- McGrew Reservoir is a lake in Weld 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 McGrew Reservoir?
- McGrew Reservoir in Weld County, Colorado is not rated for water quality — its monitoring record does not meet the evidence bar. Surface area: 116 acres.
Is McGrew Reservoir safe to swim in?
- Not rated for swimming — there is not enough monitoring data to judge this lake. McGrew 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 McGrew Reservoir come from the EPA Water Quality Portal. Per-sample source details are not recorded for this lake.