Old Man Lake
Old Man Lake in Idaho County, Idaho is not rated for water quality — its monitoring record does not meet the evidence bar. Surface area: 46 acres.
- Area
- 46 acres
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Why Old Man Lake 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 Old Man Lake, 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 IDEQ and volunteer programs, and published through the EPA Water Quality Portal. Read the full grading methodology.
Old Man Lake is a 46-acre lake in Idaho County, Idaho.
Source: EPA Water Quality Portal sampling records, IDEQ, 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 Old Man Lake
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 Old Man Lake
Compare lakeside cabins, hotels, and vacation rentals near Old Man Lake in Idaho County, Idaho — 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 Old Man Lake
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Lake Details
| Characteristic | Value |
|---|---|
| Surface Area | 46 acres |
No bathymetric survey has been published for Old Man Lake, so its depth is not documented here.
Fishing Old Man Lake
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Frequently asked questions about Old Man Lake
Where is Old Man Lake?
- Old Man Lake is a lake in Idaho County, Idaho. LakeQuality has not rated this lake (UNRATED) — no water-quality sampling on record for this lake.
What is the water quality grade for Old Man Lake?
- Old Man Lake in Idaho County, Idaho is not rated for water quality — its monitoring record does not meet the evidence bar. Surface area: 46 acres.
Is Old Man Lake safe to swim in?
- Not rated for swimming — there is not enough monitoring data to judge this lake. Old Man Lake 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 Old Man Lake come from the EPA Water Quality Portal. Per-sample source details are not recorded for this lake.