Lake Kemah
Sussex County, New Jersey102 acresView mapDirections
NJDEP publishes the water-quality measurements for Lake Kemah. Here is what has been measured.
- Eutrophic
- Impaired · Impaired biota (cause unknown)
- Limited data
Lake Kemah in Sussex County, New Jersey has water-quality measurements published by NJDEP, shown here as reported. Water clarity: 5.4 ft visibility. Phosphorus: 20 µg/L. Chlorophyll-a (algae): 22.1 µg/L. Surface area: 102 acres.
Lake Kemah is a 102-acre productive, nutrient-rich eutrophic lake in Sussex County, New Jersey. Compared to the 17 other monitored lakes in Sussex County, Lake Kemah ranks #17 for water quality.
Source: EPA Water Quality Portal sampling records, your state environmental agency, last sampled 2022-11-22. Methodology: how these readings are compared.
Swimming conditions
Readings onlyBacteria advisory
Based on clarity and algae readings from past sampling — there is no live water temperature and a current cyanobacteria reading for this lake. Check your state or county health department before you swim.
Nutrient and algae readings are not a swimming clearance. Lake Kemah is listed impaired under Clean Water Act §303(d) (IR 5) for impaired biota (cause unknown), metals (other than mercury), pathogens (E. coli, fecal). Check local advisories before you swim.
Whether Lake Kemah 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 Lake Kemah
These are the measurements NJDEP publishes for Lake Kemah, shown as reported. The condition class beside each reading is the EPA National Lakes Assessment class for this lake’s ecoregion.
Murky, only visible to about 5.4 ft. Phosphorus 20 µg/L. Chlorophyll-a 22.1 µg/L. TSI 54.
| Measure | Reading | Where it sits |
|---|---|---|
| Water clarity (Secchi depth) | 5.4ft | Measured, not scored How deep a black-and-white disk stays visible from the surface. Higher is clearer. |
| Total phosphorus | 20µg/L | Fair GoodFairPoor |
| Chlorophyll-a (algae) | 22.1µg/L | Poor GoodFairPoor |
| Trophic state (TSI)Carlson's 0–100 index of how much algae a lake can support, from clarity, phosphorus and chlorophyll-a. | 54 | Eutrophic OligotrophicMesotrophicEutrophicHypereutrophic |
High nutrients, frequent algae, reduced clarity
Ask about Lake Kemah
Answers come straight from the public measurements and survey records on this page.
Lake Details
Surface area
102 acres
No bathymetric survey has been published for Lake Kemah, so its depth is not documented here.
Stays via Stay22
Stays near Lake Kemah
Compare lakeside cabins, hotels, and vacation rentals near Lake Kemah in Sussex 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. The water-quality readings cover nutrients and algae, not lodging. Cabins and rentals around Lake Kemah are listed below.
Top-rated places to stay near Lake Kemah
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Fishing Lake Kemah
Reservoir Info (USACE NID)
Lake Kemah is a man-made reservoir impounded by the Kemah Lake Dam (completed 1928), built primarily for recreation on the Paulkinskill River-TR; earth-type dam, 17 ft tall and 240 ft long.
- Surface area
- 102 ac
- Normal storage
- 608 ac-ft
- Drainage area
- 1.3 sq mi
- Hazard class
- High
- Owner
- Kemah Lake Property Owners Association
Source: USACE National Inventory of Dams, NID ID NJ00268 · Operator website
EPA Impairment Status
Lake Kemah 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, Recreation.
A Total Maximum Daily Load (TMDL) plan has been approved.
Source: EPA ATTAINS assessment unit NJ02040105040030-01 · Official waterbody report
Nearby Lakes in Sussex County
Frequently asked questions about Lake Kemah
Where is Lake Kemah?
- Lake Kemah is a lake in Sussex County, New Jersey. Its water-quality measurements are published by NJDEP and shown on this page as reported.
What is the water quality of Lake Kemah?
- Lake Kemah in Sussex County, New Jersey has water-quality measurements published by NJDEP, shown here as reported. Water clarity: 5.4 ft visibility. Phosphorus: 20 µg/L. Chlorophyll-a (algae): 22.1 µg/L. Surface area: 102 acres.
Is Lake Kemah safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Lake Kemah is listed impaired under Clean Water Act §303(d) (IR 5) for impaired biota (cause unknown), metals (other than mercury), pathogens (E. coli, fecal). Check local advisories before you swim.
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Where this data comes from
48 measurements from 3 monitoring stations, 2022. Retrieved from the EPA Water Quality Portal on 2026-08-21.
Collected and reported by
- NJDEP Bureau of Freshwater and Biological Monitoring
NJDEP_BFBM48 samples · 2022
Analytical methods
- Phosphorus by Colorimetry
- 445.0 ~ EPA; Chlorophyll and Pheophytin in Algae by Fluorescence
Monitoring station identifiers (3)
EPA condition classes from the National Lakes Assessment (EPA 841-R-24-006, Table 6-3), applied by ecoregion. See where the data comes from and data sources.
Other records on this page
Impairment status from EPA ATTAINS 303(d) database