Longwood Lake
Morris County, New Jersey51 acresView mapDirections
No nutrient or algae sampling on record from NJDEP for this lake.
- Impaired · Mercury
- 9 ft max depth
Longwood Lake in Morris County, New Jersey has water-quality measurements published by NJDEP, shown here as reported. Maximum depth: 8.9 ft. Surface area: 51 acres.
Longwood Lake is a 51-acre lake in Morris County, New Jersey with a maximum depth of 9 feet.
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. Longwood Lake is listed impaired under Clean Water Act §303(d) (IR 5) for mercury, metals (other than mercury), pH / acidity, salinity / chlorides. Check local advisories before you swim.
Whether Longwood 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.
Water quality measurements for Longwood Lake
These are the measurements NJDEP publishes for Longwood 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 Longwood Lake
Answers come straight from the public measurements and survey records on this page.
Lake Details
Max depth
8.9 ft
Surface area
51 acres
Shoreline
3.8 mi
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Fishing Longwood Lake
EPA Impairment Status
Longwood Lake is officially listed as impaired under Clean Water Act §303(d) in the 2022 EPA reporting cycle (IR category 5).
Causes of impairment
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 NJ02030103030030-01 · Official waterbody report
Nearby Lakes in Morris County
Frequently asked questions about Longwood Lake
Where is Longwood Lake?
- Longwood 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 Longwood Lake?
- Longwood Lake in Morris County, New Jersey has water-quality measurements published by NJDEP, shown here as reported. Maximum depth: 8.9 ft. Surface area: 51 acres.
Is Longwood Lake safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Longwood Lake is listed impaired under Clean Water Act §303(d) (IR 5) for mercury, metals (other than mercury), pH / acidity, salinity / chlorides. Check local advisories before you swim.
How deep is Longwood Lake?
- Longwood Lake has a maximum depth of 8.9 feet. The lake covers 51 acres.
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Where this data comes from
Measurements for Longwood Lake come from the EPA Water Quality Portal. Per-sample source details are not recorded for this lake.
Other records on this page
Impairment status from EPA ATTAINS 303(d) database