Curlis Lake
Mercer County, New Jersey18 acresView mapDirections
NJDEP publishes the water-quality measurements for Curlis Lake. Here is what has been measured.
- Hypereutrophic
- Impaired · Pathogens (E. coli, fecal)
- Limited data
Curlis Lake in Mercer County, New Jersey has water-quality measurements published by NJDEP, shown here as reported. Water clarity: 2.4 ft visibility. Phosphorus: 121 µg/L. Chlorophyll-a (algae): 49.8 µg/L. Surface area: 18 acres.
Curlis Lake is a 18-acre highly nutrient-loaded hypereutrophic lake in Mercer County, New Jersey. Compared to the 14 other monitored lakes in Mercer County, Curlis Lake ranks #4 for water quality.
Source: EPA Water Quality Portal sampling records, your state environmental agency, last sampled 2022-11-07. 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. Curlis Lake is listed impaired under Clean Water Act §303(d) (IR 5) for pathogens (E. coli, fecal). Check local advisories before you swim.
Whether Curlis 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 Curlis Lake
These are the measurements NJDEP publishes for Curlis Lake, shown as reported. The condition class beside each reading is the EPA National Lakes Assessment class for this lake’s ecoregion.
Very murky, less than 2.4 ft of visibility. Phosphorus 121 µg/L. Chlorophyll-a 49.8 µg/L. TSI 69.
| Measure | Reading | Where it sits |
|---|---|---|
| Water clarity (Secchi depth) | 2.4ft | Measured, not scored How deep a black-and-white disk stays visible from the surface. Higher is clearer. |
| Total phosphorus | 121µg/L | Poor GoodFairPoor |
| Chlorophyll-a (algae) | 49.8µg/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. | 69 | Hypereutrophic OligotrophicMesotrophicEutrophicHypereutrophic |
Very high nutrients, dense algae, poor clarity
Ask about Curlis Lake
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Lake Details
Surface area
18 acres
No bathymetric survey has been published for Curlis Lake, so its depth is not documented here.
Stays via Stay22
Stays near Curlis Lake
Compare lakeside cabins, hotels, and vacation rentals near Curlis Lake in Mercer 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 Curlis Lake are listed below.
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Fishing Curlis Lake
Reservoir Info (USACE NID)
Curlis Lake is a man-made reservoir impounded by the Stony Brook #4 (Curlis Lake) Dam (completed 1959), built primarily for flood risk reduction on the Stony Brook-TR; earth-type dam, 24 ft tall and 340 ft long.
- Surface area
- 18 ac
- Normal storage
- 100 ac-ft
- Max storage
- 285 ac-ft
- Drainage area
- 1.7 sq mi
- Hazard class
- Low
- Owner
- County of Mercer Park Commission
Source: USACE National Inventory of Dams, NID ID NJ00390 · Operator website · Matched by proximity (0.3 km)
EPA Impairment Status
Curlis 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: Recreation.
Source: EPA ATTAINS assessment unit NJ02030105090040-01 · Official waterbody report
Nearby Lakes in Mercer County
Frequently asked questions about Curlis Lake
Where is Curlis Lake?
- Curlis Lake is a lake in Mercer County, New Jersey. Its water-quality measurements are published by NJDEP and shown on this page as reported.
What is the water quality of Curlis Lake?
- Curlis Lake in Mercer County, New Jersey has water-quality measurements published by NJDEP, shown here as reported. Water clarity: 2.4 ft visibility. Phosphorus: 121 µg/L. Chlorophyll-a (algae): 49.8 µg/L. Surface area: 18 acres.
Is Curlis Lake safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Curlis Lake is listed impaired under Clean Water Act §303(d) (IR 5) for pathogens (E. coli, fecal). Check local advisories before you swim.
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Where this data comes from
32 measurements from 2 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_BFBM32 samples · 2022
Analytical methods
- Phosphorus by Colorimetry
- 445.0 ~ EPA; Chlorophyll and Pheophytin in Algae by Fluorescence
Monitoring station identifiers (2)
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