Pataganset Lake
Pataganset Lake in New London County, Connecticut has a water quality grade of C (Fair). Phosphorus: 20 µg/L. Chlorophyll-a (algae): 7.6 µg/L. Surface area: 120 acres.
- Area
- 120 acres
- Type
- Mesotrophic
Pataganset Lake is a 120-acre mesotrophic lake in New London County, Connecticut. Water quality is graded C based on 2 sampling years through 2023. Compared to the 9 other monitored lakes in New London County, Pataganset Lake ranks #9 for water quality.
Source: EPA Water Quality Portal sampling records, your state environmental agency, last sampled 2023-07-27. Grade methodology: LakeGrade methodology.
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Swimming Safety
Grade onlyLimited data
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.
Generally safe for swimming, moderate water quality
Water Quality Grade: C (Fair)
No clarity data. Phosphorus level: 20 µg/L. Chlorophyll-a: 7.6 µg/L. Trophic State Index: 49.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | No recent samples | |
| Phosphorus | 20 µg/L | Fair |
| Chlorophyll-a (Algae) | 7.6 µg/L | Not graded |
| Trophic State Index (TSI) | 49 | Mesotrophic |
Moderate nutrients, good water quality
Where to stay near Pataganset Lake
Compare lakeside cabins, hotels, and vacation rentals near Pataganset Lake in New London County, Connecticut — 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 Pataganset Lake
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Lake Details
| Characteristic | Value |
|---|---|
| Surface Area | 120 acres |
No bathymetric survey has been published for Pataganset Lake, so its depth is not documented here.
Fishing Pataganset Lake
Reservoir Info (USACE NID)
Pataganset Lake is a man-made reservoir impounded by the Pataguanset Lake Dam (completed 1942), built primarily for recreation on the Pataguanset River; earth-type dam, 12 ft tall and 210 ft long.
- Surface area
- 120 ac
- Normal storage
- 310 ac-ft
- Max storage
- 950 ac-ft
- Drainage area
- 3.91 sq mi
- Hazard class
- High
- Owner
- Connecticut DEEP
Source: USACE National Inventory of Dams, NID ID CT00159 · Operator website · Matched by proximity (0.56 km)
County Ranking
Ranked #9 of 10 lakes in New London County
Nearby Lakes in New London County
Frequently asked questions about Pataganset Lake
Where is Pataganset Lake?
- Pataganset Lake is a lake in New London County, Connecticut. LakeQuality grades it C for nutrients and algae. The letter is not a swimming clearance.
What is the water quality grade for Pataganset Lake?
- Pataganset Lake in New London County, Connecticut has a water quality grade of C (Fair). Phosphorus: 20 µg/L. Chlorophyll-a (algae): 7.6 µg/L. Surface area: 120 acres.
Is Pataganset Lake safe to swim in?
- Generally safe for swimming, moderate water quality. Pataganset Lake has a water quality grade of C (Fair). Algae concentration (chlorophyll-a) is 7.6 µg/L. Always check local health department advisories before swimming.
Explore Pataganset Lake across LakeGrade
More Connecticut Lake Rankings
Other Grade C Lakes in Connecticut
Mesotrophic Lakes in Connecticut
Where this data comes from
10 measurements from 1 monitoring station, 2023. Retrieved from the EPA Water Quality Portal on 2026-08-21.
Collected and reported by
- Connecticut Department Of Energy And Environmental Protection
CT_DEP01_WQX10 samples · 2023
Analytical methods
- Total Phosphorus After Block Digestion
- 445.0 ~ EPA; Chlorophyll and Pheophytin in Algae by Fluorescence
- Nitrate-Nitrite Nitrogen by Colorimetry
- Turbidity by Nephelometry
Monitoring station identifiers (1)
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.