Ashton Reservoir
Ashton Reservoir in Fremont County, Idaho is not rated for water quality — its monitoring record does not meet the evidence bar. Surface area: 287 acres.
- Area
- 287 acres
Next lake in Fremont County
Swipe left or right on this bar to open the next or previous lake.
Why Ashton 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 Ashton 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 IDEQ and volunteer programs, and published through the EPA Water Quality Portal. Read the full grading methodology.
Ashton Reservoir is a 287-acre lake in Fremont County, Idaho.
Source: EPA Water Quality Portal sampling records, IDEQ, last sampled recent years. Grade methodology: LakeQuality methodology.
Watch Ashton Reservoir water quality
Subscribe for LakeQuality updates by email. No spam, unsubscribe anytime.
Swimming Safety
Not ratedElevated nutrients
Not rated for swimming — there is not enough monitoring data to judge this lake
Water quality measurements for Ashton 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 Ashton Reservoir
Compare lakeside cabins, hotels, and vacation rentals near Ashton Reservoir in Fremont 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 Ashton Reservoir
Availability and prices from Stay22 partners (Booking.com, Vrbo, Expedia). We may earn a commission from bookings, at no extra cost to you.
Planning a whole trip? See where to stay at Idaho’s top lakes →
Lake Details
| Characteristic | Value |
|---|---|
| Surface Area | 287 acres |
No bathymetric survey has been published for Ashton Reservoir, so its depth is not documented here.
Fishing Ashton Reservoir
Nearby Lakes in Fremont County
Frequently asked questions about Ashton Reservoir
Where is Ashton Reservoir?
- Ashton Reservoir is a lake in Fremont 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 Ashton Reservoir?
- Ashton Reservoir in Fremont County, Idaho is not rated for water quality — its monitoring record does not meet the evidence bar. Surface area: 287 acres.
Is Ashton Reservoir safe to swim in?
- Not rated for swimming — there is not enough monitoring data to judge this lake. Ashton Reservoir is not rated for water quality — its monitoring record does not meet the evidence bar. Always check local health department advisories before swimming.
Explore Ashton Reservoir across LakeQuality
More Idaho Lake Rankings
Other Lakes in Idaho
Where this data comes from
Measurements for Ashton Reservoir come from the EPA Water Quality Portal. Per-sample source details are not recorded for this lake.