Where is Lake Hennessey?

Lake Hennessey is a lake in Napa County, California. Its water-quality measurements are published by SWRCB and shown on this page as reported.

How deep is Lake Hennessey?

Lake Hennessey has a maximum depth of 85 feet. The lake covers 763 acres.

Lake Hennessey

Napa County, California763 acresView map Directions

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

Max depth

85 ft

Bathymetric survey

Area

763 acres

Surface area

Shoreline

10 mi

Measured length

85 ft max depth
Limited data

See the measurements Directions Where to stay

Lake Hennessey in Napa County, California has water-quality measurements published by SWRCB, shown here as reported. Maximum depth: 85 ft. Surface area: 763 acres.

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Lake Hennessey is a 763-acre lake in Napa County, California with a maximum depth of 85 feet.

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

What Lake Hennessey is good for

From access and monitoring records, not editorial picks.

Deep water85 ft surveyed max depth

Swimming conditions

No reading

Limited data

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

Whether Lake Hennessey 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.

Get alerts for Lake Hennessey →

Water quality measurements for Lake Hennessey

These are the measurements SWRCB publishes for Lake Hennessey, 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 Hennessey

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

Lake Details

Max depth

85 ft

Surface area

763 acres

Shoreline

10 mi

Stays via Stay22

Stays near Lake Hennessey

Compare lakeside cabins, hotels, and vacation rentals near Lake Hennessey in Napa 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 Hennessey

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Follow Lake Hennessey’s readings

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Fishing Lake Hennessey

→ Lake Hennessey fishing regulations (limits, seasons, special rules)

Nearby Lakes in Napa County

Rector Reservoir4 miView →Bell Canyon Reservoir7.5 miView →Weeks Lake11.2 miView →Lake Berryessa10.4 miView →Milliken Reservoir11 miView →Moskowitz Reservoir10.2 miView →

Frequently asked questions about Lake Hennessey

Where is Lake Hennessey?: Lake Hennessey is a lake in Napa County, California. Its water-quality measurements are published by SWRCB and shown on this page as reported.
What is the water quality of Lake Hennessey?: Lake Hennessey in Napa County, California has water-quality measurements published by SWRCB, shown here as reported. Maximum depth: 85 ft. Surface area: 763 acres.
Is Lake Hennessey safe to swim in?: Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.
How deep is Lake Hennessey?: Lake Hennessey has a maximum depth of 85 feet. The lake covers 763 acres.