Where is Lake O'Neill?

Lake O'Neill is a lake in San Diego County, California. Its water-quality measurements are published by SWRCB and shown on this page as reported.

Lake O'Neill

San Diego County, California97 acresView map Directions

No nutrient or algae sampling on record from SWRCB for this lake.

Area

97 acres

Surface area

Shoreline

2.7 mi

Measured length

Limited data

See the measurements Directions Where to stay

Lake O'Neill in San Diego County, California has water-quality measurements published by SWRCB, shown here as reported. Surface area: 97 acres.

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Lake O'Neill is a 97-acre lake in San Diego County, California.

Source: EPA Water Quality Portal sampling records, your state environmental agency. Methodology: how these readings are compared.

Swimming conditions

No reading

Limited data

Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.

Whether Lake O'Neill 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.

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Water quality measurements for Lake O'Neill

These are the measurements SWRCB publishes for Lake O'Neill, shown as reported. The condition class beside each reading is the EPA National Lakes Assessment class for this lake’s ecoregion.

No clarity data.

Ask about Lake O'Neill

Answers come straight from the public measurements and survey records on this page.

Lake Details

Surface area

97 acres

Shoreline

2.7 mi

No bathymetric survey has been published for Lake O'Neill, so its depth is not documented here.

Stays via Stay22

Stays near Lake O'Neill

Compare lakeside cabins, hotels, and vacation rentals near Lake O'Neill in San Diego County, California — 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 Lake O'Neill

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Fishing Lake O'Neill

→ Lake O'Neill fishing regulations (limits, seasons, special rules)

Nearby Lakes in San Diego County

Windmill Lake5.4 miView →Whelan Lake6 miView →Guajome Lake6.4 miView →Lake San Marcos16 miView →Turner Lake15.9 miView →San Dieguito Reservoir21.4 miView →

Frequently asked questions about Lake O'Neill

Where is Lake O'Neill?: Lake O'Neill is a lake in San Diego County, California. Its water-quality measurements are published by SWRCB and shown on this page as reported.
What is the water quality of Lake O'Neill?: Lake O'Neill in San Diego County, California has water-quality measurements published by SWRCB, shown here as reported. Surface area: 97 acres.
Is Lake O'Neill safe to swim in?: Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.