Foster Reservoir
Foster Reservoir in Franklin County, Idaho is not rated for water quality — its monitoring record does not meet the evidence bar. Surface area: 66 acres.
- Area
- 66 acres
- Public access
- Yes
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Why Foster 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 Foster 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.
Foster Reservoir is a 66-acre lake in Franklin County, Idaho. Limited fish-species data available. Public access is available with 1 public boat landing.
Source: EPA Water Quality Portal sampling records, IDEQ, last sampled recent years. Grade methodology: LakeQuality methodology.
Watch Foster Reservoir 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 Foster 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 Foster Reservoir
Compare lakeside cabins, hotels, and vacation rentals near Foster Reservoir in Franklin 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 Foster Reservoir
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Lake Details
| Characteristic | Value |
|---|---|
| Surface Area | 66 acres |
| Public Access | Yes |
No bathymetric survey has been published for Foster Reservoir, so its depth is not documented here.
Recreation & Access
- Foster ReservoirPublic
Named access points in the USGS National Boat Ramps inventory, within about 3 miles. More lakes with boat ramps
Fishing Foster Reservoir
Nearby Lakes in Franklin County
Frequently asked questions about Foster Reservoir
Where is Foster Reservoir?
- Foster Reservoir is a lake in Franklin 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 Foster Reservoir?
- Foster Reservoir in Franklin County, Idaho is not rated for water quality — its monitoring record does not meet the evidence bar. Surface area: 66 acres.
Is Foster Reservoir safe to swim in?
- Not rated for swimming — there is not enough monitoring data to judge this lake. Foster Reservoir is not rated for water quality — its monitoring record does not meet the evidence bar. Always check local health department advisories before swimming.
Are there boat ramps on Foster Reservoir?
- Foster Reservoir has 1 documented boat landing in the USGS National Boat Ramps inventory. Named access points include Foster Reservoir. Public access is listed as yes.
Explore Foster Reservoir across LakeQuality
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Where this data comes from
Measurements for Foster Reservoir come from the EPA Water Quality Portal. Per-sample source details are not recorded for this lake.
Other records on this page
Named boat-access points from the USGS National Boat Ramps inventory