Granite Lake
Granite Lake in Valley County, Idaho is not rated for water quality — its monitoring record does not meet the evidence bar. Surface area: 112 acres.
- Area
- 112 acres
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Why Granite 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 Granite 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.
Granite Lake is a 112-acre lake in Valley County, Idaho.
Source: EPA Water Quality Portal sampling records, IDEQ, last sampled recent years. Grade methodology: LakeQuality methodology.
Watch Granite Lake 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 Granite 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 Granite Lake
Compare lakeside cabins, hotels, and vacation rentals near Granite Lake in Valley 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 Granite Lake
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Lake Details
| Characteristic | Value |
|---|---|
| Surface Area | 112 acres |
No bathymetric survey has been published for Granite Lake, so its depth is not documented here.
Fishing Granite Lake
Nearby Lakes in Valley County
Frequently asked questions about Granite Lake
Where is Granite Lake?
- Granite Lake is a lake in Valley 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 Granite Lake?
- Granite Lake in Valley County, Idaho is not rated for water quality — its monitoring record does not meet the evidence bar. Surface area: 112 acres.
Is Granite Lake safe to swim in?
- Not rated for swimming — there is not enough monitoring data to judge this lake. Granite 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 Granite Lake come from the EPA Water Quality Portal. Per-sample source details are not recorded for this lake.