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

Moon Lake

Lassen County, California2,238 acresView map Directions

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

Area

2,238 acres

Surface area

Shoreline

12.7 mi

Measured length

Impaired · Mercury
Limited data

See the measurements Directions Where to stay

Moon Lake in Lassen County, California has water-quality measurements published by SWRCB, shown here as reported. Surface area: 2238 acres.

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Moon Lake is a 2,238-acre lake in Lassen County, California.

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

What Moon Lake is good for

From access and monitoring records, not editorial picks.

Big water2,238 acres

Swimming conditions

No reading

Limited data

Nutrient and algae readings are not a swimming clearance. Moon Lake is listed impaired under Clean Water Act §303(d) (IR 5) for mercury. Check local advisories before you swim.

Whether Moon Lake 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 Moon Lake

These are the measurements SWRCB publishes for Moon Lake, 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 Moon Lake

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

Lake Details

Surface area

2,238 acres

Shoreline

12.7 mi

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

Stays via Stay22

Stays near Moon Lake

Compare lakeside cabins, hotels, and vacation rentals near Moon Lake in Lassen 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 Moon Lake

Prices for Oct 16–18, 4 adults. Change dates on the map below.

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Follow Moon Lake’s readings

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Fishing Moon Lake

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

EPA Impairment Status

Moon Lake is officially listed as impaired under Clean Water Act §303(d) in the 2024 EPA reporting cycle (IR category 5).

Causes of impairment

Mercury

Designated uses not supporting: Fish consumption, Other.

Source: EPA ATTAINS assessment unit CAL5265304120091208193713 · Official waterbody report

Nearby Lakes in Lassen County

Mendiboure Reservoir6.3 miView →Blue Lake7.1 miView →Nelson Corral Reservoir8.2 miView →Red Rock Lake10.4 miView →Holbrook Reservoir11.7 miView →Spooner Reservoir12.7 miView →

Frequently asked questions about Moon Lake

Where is Moon Lake?: Moon Lake is a lake in Lassen County, California. Its water-quality measurements are published by SWRCB and shown on this page as reported.
What is the water quality of Moon Lake?: Moon Lake in Lassen County, California has water-quality measurements published by SWRCB, shown here as reported. Surface area: 2238 acres.
Is Moon Lake safe to swim in?: Nutrient and algae readings are not a swimming clearance. Moon Lake is listed impaired under Clean Water Act §303(d) (IR 5) for mercury. Check local advisories before you swim.