Where is Mountain Lake?

Mountain Lake is a lake in Morris County, New Jersey. Its water-quality measurements are published by NJDEP and shown on this page as reported.

Mountain Lake

Morris County, New Jersey75 acresView map Directions

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

Area

75 acres

Surface area

Shoreline

3 mi

Measured length

Impaired · Impaired biota (cause unknown)

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Mountain Lake in Morris County, New Jersey has water-quality measurements published by NJDEP, shown here as reported. Surface area: 75 acres.

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Mountain Lake is a 75-acre lake in Morris County, New Jersey.

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

Swimming conditions

No reading

Not rated

Nutrient and algae readings are not a swimming clearance. Mountain Lake is listed impaired under Clean Water Act §303(d) (IR 5) for impaired biota (cause unknown), mercury, metals (other than mercury), nutrients (phosphorus, nitrogen). Check local advisories before you swim.

Whether Mountain Lake is safe to swim in today is a call for the New Jersey Department of Environmental Protection and the county health department, who post current advisories. LakeQuality does not issue swimming clearances.

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Water quality measurements for Mountain Lake

These are the measurements NJDEP publishes for Mountain 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. TSI undefined.

Ask about Mountain Lake

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

Lake Details

Surface area

75 acres

Shoreline

3 mi

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

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Stays near Mountain Lake

Compare lakeside cabins, hotels, and vacation rentals near Mountain Lake in Morris County, New Jersey — 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 Mountain Lake

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Fishing Mountain Lake

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

EPA Impairment Status

Mountain Lake is officially listed as impaired under Clean Water Act §303(d) in the 2022 EPA reporting cycle (IR category 5).

Causes of impairment

Impaired biota (cause unknown)MercuryMetals (other than mercury)Nutrients (phosphorus, nitrogen)

Designated uses not supporting: Drinking water, Aquatic life, Fish consumption.

A Total Maximum Daily Load (TMDL) plan has been approved.

Source: EPA ATTAINS assessment unit NJ02030103020080-01 · Official waterbody report

Nearby Lakes in Morris County

Lake Parsippany2.5 miView →Cedar Lake2.2 miView →Boonton Reservoir2 miView →Indian Lake2.2 miView →Dixons Pond3.5 miView →Lake Estling2.9 miView →

Frequently asked questions about Mountain Lake

Where is Mountain Lake?: Mountain Lake is a lake in Morris County, New Jersey. Its water-quality measurements are published by NJDEP and shown on this page as reported.
What is the water quality of Mountain Lake?: Mountain Lake in Morris County, New Jersey has water-quality measurements published by NJDEP, shown here as reported. Surface area: 75 acres.
Is Mountain Lake safe to swim in?: Nutrient and algae readings are not a swimming clearance. Mountain Lake is listed impaired under Clean Water Act §303(d) (IR 5) for impaired biota (cause unknown), mercury, metals (other than mercury), nutrients (phosphorus, nitrogen). Check local advisories before you swim.