South Arm Reservoir
South Arm Reservoir in Lake County, Oregon is not rated for water quality — its monitoring record does not meet the evidence bar. Surface area: 103 acres.
- Area
- 103 acres
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Why South Arm 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 Arm 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 Oregon DEQ and volunteer programs, and published through the EPA Water Quality Portal. Read the full grading methodology.
South Arm Reservoir is a 103-acre lake in Lake County, Oregon.
Source: EPA Water Quality Portal sampling records, Oregon DEQ, last sampled recent years. Grade methodology: LakeQuality methodology.
Watch South Arm 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 South Arm 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 Arm Reservoir
Compare lakeside cabins, hotels, and vacation rentals near South Arm Reservoir in Lake County, Oregon — 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 South Arm Reservoir
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Lake Details
| Characteristic | Value |
|---|---|
| Surface Area | 103 acres |
No bathymetric survey has been published for South Arm Reservoir, so its depth is not documented here.
Fishing South Arm Reservoir
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Frequently asked questions about South Arm Reservoir
Where is South Arm Reservoir?
- South Arm Reservoir is a lake in Lake County, Oregon. LakeQuality has not rated this lake (UNRATED) — no water-quality sampling on record for this lake.
What is the water quality grade for South Arm Reservoir?
- South Arm Reservoir in Lake County, Oregon is not rated for water quality — its monitoring record does not meet the evidence bar. Surface area: 103 acres.
Is South Arm Reservoir safe to swim in?
- Not rated for swimming — there is not enough monitoring data to judge this lake. South Arm Reservoir 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 South Arm Reservoir come from the EPA Water Quality Portal. Per-sample source details are not recorded for this lake.