South Sandstone Reservoir
South Sandstone Reservoir in Fallon County, Montana is not rated for water quality — its monitoring record does not meet the evidence bar. Surface area: 108 acres.
- Area
- 108 acres
- Public access
- Yes
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Why South Sandstone 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 South Sandstone 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 Montana DEQ and volunteer programs, and published through the EPA Water Quality Portal. Read the full grading methodology.
South Sandstone Reservoir is a 108-acre lake in Fallon County, Montana. Limited fish-species data available. Public access is available with 1 public boat landing.
Source: EPA Water Quality Portal sampling records, Montana DEQ, 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 South Sandstone 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 South Sandstone Reservoir
Compare lakeside cabins, hotels, and vacation rentals near South Sandstone Reservoir in Fallon County, Montana — 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.
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Lake Details
| Characteristic | Value |
|---|---|
| Surface Area | 108 acres |
| Public Access | Yes |
No bathymetric survey has been published for South Sandstone Reservoir, so its depth is not documented here.
Recreation & Access
- South SandstonePublic
Named access points in the USGS National Boat Ramps inventory, within about 3 miles. More lakes with boat ramps
Fishing South Sandstone Reservoir
Nearby Lakes in Fallon County
Frequently asked questions about South Sandstone Reservoir
Where is South Sandstone Reservoir?
- South Sandstone Reservoir is a lake in Fallon County, Montana. LakeQuality has not rated this lake (UNRATED) — no water-quality sampling on record for this lake.
What is the water quality grade for South Sandstone Reservoir?
- South Sandstone Reservoir in Fallon County, Montana is not rated for water quality — its monitoring record does not meet the evidence bar. Surface area: 108 acres.
Is South Sandstone Reservoir safe to swim in?
- Not rated for swimming — there is not enough monitoring data to judge this lake. South Sandstone 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 South Sandstone Reservoir?
- South Sandstone Reservoir has 1 documented boat landing in the USGS National Boat Ramps inventory. Named access points include South Sandstone. Public access is listed as yes.
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Where this data comes from
Measurements for South Sandstone 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