Grub Detention Reservoir
Grub Detention Reservoir in Valley County, Montana is not rated for water quality — its monitoring record does not meet the evidence bar. Surface area: 229 acres.
- Area
- 229 acres
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Why Grub Detention 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 Grub Detention 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 Montana DEQ and volunteer programs, and published through the EPA Water Quality Portal. Read the full grading methodology.
Grub Detention Reservoir is a 229-acre lake in Valley County, Montana.
Source: EPA Water Quality Portal sampling records, Montana DEQ, last sampled recent years. Grade methodology: LakeQuality methodology.
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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 Grub Detention 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 Grub Detention Reservoir
Compare lakeside cabins, hotels, and vacation rentals near Grub Detention Reservoir in Valley County, Montana — 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.
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Lake Details
| Characteristic | Value |
|---|---|
| Surface Area | 229 acres |
No bathymetric survey has been published for Grub Detention Reservoir, so its depth is not documented here.
Fishing Grub Detention Reservoir
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Frequently asked questions about Grub Detention Reservoir
Where is Grub Detention Reservoir?
- Grub Detention Reservoir is a lake in Valley County, Montana. LakeQuality has not rated this lake (UNRATED) — no water-quality sampling on record for this lake.
What is the water quality grade for Grub Detention Reservoir?
- Grub Detention Reservoir in Valley County, Montana is not rated for water quality — its monitoring record does not meet the evidence bar. Surface area: 229 acres.
Is Grub Detention Reservoir safe to swim in?
- Not rated for swimming — there is not enough monitoring data to judge this lake. Grub Detention 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 Grub Detention Reservoir come from the EPA Water Quality Portal. Per-sample source details are not recorded for this lake.