Foss Reservoir
Foss Reservoir in Custer County, Oklahoma is not rated for water quality — its monitoring record does not meet the evidence bar. Surface area: 6381 acres.
- Area
- 6,381 acres
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Why Foss 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 Foss 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 ODEQ and volunteer programs, and published through the EPA Water Quality Portal. Read the full grading methodology.
Foss Reservoir is a 6,381-acre lake in Custer County, Oklahoma.
Source: EPA Water Quality Portal sampling records, ODEQ, 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 Foss 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 Foss Reservoir
Compare lakeside cabins, hotels, and vacation rentals near Foss Reservoir in Custer County, Oklahoma — 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 Foss Reservoir
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Lake Details
| Characteristic | Value |
|---|---|
| Surface Area | 6,381 acres |
No bathymetric survey has been published for Foss Reservoir, so its depth is not documented here.
Fishing Foss Reservoir
Nearby Lakes in Custer County
Frequently asked questions about Foss Reservoir
Where is Foss Reservoir?
- Foss Reservoir is a lake in Custer County, Oklahoma. LakeQuality has not rated this lake (UNRATED) — no water-quality sampling on record for this lake.
What is the water quality grade for Foss Reservoir?
- Foss Reservoir in Custer County, Oklahoma is not rated for water quality — its monitoring record does not meet the evidence bar. Surface area: 6381 acres.
Is Foss Reservoir safe to swim in?
- Not rated for swimming — there is not enough monitoring data to judge this lake. Foss 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 Foss Reservoir come from the EPA Water Quality Portal. Per-sample source details are not recorded for this lake.