South Mountain Reservoir
Modoc County, California186 acresView mapDirections
No nutrient or algae sampling on record from SWRCB for this lake.
South Mountain Reservoir in Modoc County, California has water-quality measurements published by SWRCB, shown here as reported. Surface area: 186 acres.
South Mountain Reservoir is a 186-acre lake in Modoc County, California.
Source: EPA Water Quality Portal sampling records, your state environmental agency. Methodology: how these readings are compared.
Swimming conditions
No readingNot rated
Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.
Whether South Mountain Reservoir is safe to swim in today is a call for the California State Water Resources Control Board and the county health department, who post current advisories. LakeQuality does not issue swimming clearances.
Water quality measurements for South Mountain Reservoir
These are the measurements SWRCB publishes for South Mountain Reservoir, shown as reported. The condition class beside each reading is the EPA National Lakes Assessment class for this lake’s ecoregion.
No clarity data. TSI undefined.
Ask about South Mountain Reservoir
Answers come straight from the public measurements and survey records on this page.
Lake Details
Surface area
186 acres
Shoreline
4 mi
No bathymetric survey has been published for South Mountain Reservoir, so its depth is not documented here.
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Stays near South Mountain Reservoir
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Frequently asked questions about South Mountain Reservoir
Where is South Mountain Reservoir?
- South Mountain Reservoir is a lake in Modoc County, California. Its water-quality measurements are published by SWRCB and shown on this page as reported.
What is the water quality of South Mountain Reservoir?
- South Mountain Reservoir in Modoc County, California has water-quality measurements published by SWRCB, shown here as reported. Surface area: 186 acres.
Is South Mountain Reservoir safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.
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Where this data comes from
Measurements for South Mountain Reservoir come from the EPA Water Quality Portal. Per-sample source details are not recorded for this lake.