Cushetunk Lake
Cushetunk Lake in Hunterdon County, New Jersey has a water quality grade of D (Nutrient-rich). Water clarity: 0.8 ft visibility. Phosphorus: 81.8 µg/L. Chlorophyll-a (algae): 27.3 µg/L. Surface area: 30 acres.
- Clarity
- 0.8 ft
- Area
- 30 acres
- Type
- Eutrophic
Grade D measures nutrients and algae, not whether this is a good place for a cabin trip. Cabins and rentals near Cushetunk Lake →
Cushetunk Lake is a 30-acre productive, nutrient-rich eutrophic lake in Hunterdon County, New Jersey. Water quality is graded D based on 1 sampling years through 2023. Compared to the 3 other monitored lakes in Hunterdon County, Cushetunk Lake ranks #3 for water quality.
Source: EPA Water Quality Portal sampling records, your state environmental agency, last sampled 2023-09-21. Grade methodology: LakeGrade methodology.
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Swimming Safety
Grade onlyBacteria advisory
Based on clarity and algae grades from past sampling — we do not hold live water temperature and a current cyanobacteria reading for this lake. Check your state or county health department before you swim.
Nutrients and algae run higher than average — check local advisories before swimming, and skip the water if you see scum
Water Quality Grade: D (Nutrient-rich)
Very murky, less than 0.8 ft of visibility. Phosphorus level: 81.8 µg/L. Chlorophyll-a: 27.3 µg/L. Trophic State Index: 70.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 0.8 ft | Not graded |
| Phosphorus | 81.8 µg/L | Not graded |
| Chlorophyll-a (Algae) | 27.3 µg/L | Poor |
| Trophic State Index (TSI) | 70 | Eutrophic |
High nutrients, frequent algae, reduced clarity
Where to stay near Cushetunk Lake
Compare lakeside cabins, hotels, and vacation rentals near Cushetunk Lake in Hunterdon 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 grade measures nutrients and algae, not lodging — cabins and rentals around Cushetunk Lake are listed below.
Top-rated places to stay near Cushetunk Lake
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Lake Details
| Characteristic | Value |
|---|---|
| Surface Area | 30 acres |
No bathymetric survey has been published for Cushetunk Lake, so its depth is not documented here.
Fishing Cushetunk Lake
Reservoir Info (USACE NID)
Cushetunk Lake is a man-made reservoir impounded by the Lake Cushetunk Dam (completed 1928), built primarily for recreation on the South Branch Rockaway Creek; earth-type dam, 20 ft tall and 594 ft long.
- Surface area
- 30 ac
- Normal storage
- 212 ac-ft
- Max storage
- 365 ac-ft
- Drainage area
- 12.5 sq mi
- Hazard class
- Significant
- Owner
- Township of Readington
Source: USACE National Inventory of Dams, NID ID NJ00347 · Operator website
EPA Impairment Status
Cushetunk Lake is officially listed as impaired under Clean Water Act §303(d) in the 2022 EPA reporting cycle (IR category 5).
Causes of impairment
A Total Maximum Daily Load (TMDL) plan has been approved.
Source: EPA ATTAINS assessment unit NJ02030105050090-01 · Official waterbody report · Matched by proximity (2.49 km)
County Ranking
Ranked #3 of 4 lakes in Hunterdon County
Nearby Lakes in Hunterdon County
Frequently asked questions about Cushetunk Lake
Where is Cushetunk Lake?
- Cushetunk Lake is a lake in Hunterdon County, New Jersey. LakeQuality grades it D for nutrients and algae. The letter is not a swimming clearance.
What is the water quality grade for Cushetunk Lake?
- Cushetunk Lake in Hunterdon County, New Jersey has a water quality grade of D (Nutrient-rich). Water clarity: 0.8 ft visibility. Phosphorus: 81.8 µg/L. Chlorophyll-a (algae): 27.3 µg/L. Surface area: 30 acres.
Is Cushetunk Lake safe to swim in?
- Nutrients and algae run higher than average — check local advisories before swimming, and skip the water if you see scum. Cushetunk Lake has a water quality grade of D (Nutrient-rich). Algae concentration (chlorophyll-a) is 27.3 µg/L. Always check local health department advisories before swimming.
Explore Cushetunk Lake across LakeGrade
More New Jersey Lake Rankings
Other Grade D Lakes in New Jersey
Eutrophic Lakes in New Jersey
Where this data comes from
77 measurements from 3 monitoring stations, 2022–2023. Retrieved from the EPA Water Quality Portal on 2026-08-21.
Collected and reported by
- NJDEP Bureau of Freshwater and Biological Monitoring
NJDEP_BFBM77 samples · 2022–2023
Analytical methods
- Phosphorus by Colorimetry
- 445.0 ~ EPA; Chlorophyll and Pheophytin in Algae by Fluorescence
Monitoring station identifiers (3)
Grade thresholds from the EPA National Lakes Assessment (EPA 841-R-24-006, Table 6-3), applied by ecoregion. See how grades are calculated and data sources.
Other records on this page
Impairment status from EPA ATTAINS 303(d) database