East Twin Lake
East Twin Lake in Litchfield County, Connecticut has a water quality grade of B (Good). Phosphorus: 10 µg/L. Chlorophyll-a (algae): 2.4 µg/L.
- Type
- Oligotrophic
East Twin Lake is a cold, clear oligotrophic lake in Litchfield County, Connecticut. Water quality is graded B based on 2 sampling years through 2023. Compared to the 11 other monitored lakes in Litchfield County, East Twin Lake ranks #3 for water quality.
Source: EPA Water Quality Portal sampling records, your state environmental agency, last sampled 2023-08-31. 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.
Good for swimming, clear water with low algae levels
Water Quality Grade: B (Good)
No clarity data. Phosphorus level: 10 µg/L. Chlorophyll-a: 2.4 µg/L. Trophic State Index: 38.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | No recent samples | |
| Phosphorus | 10 µg/L | Good |
| Chlorophyll-a (Algae) | 2.4 µg/L | Not graded |
| Trophic State Index (TSI) | 38 | Oligotrophic |
Low nutrients, clear water, excellent for swimming
Where to stay near East Twin Lake
Compare lakeside cabins, hotels, and vacation rentals near East Twin Lake in Litchfield 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 East Twin Lake
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Fishing East Twin Lake
County Ranking
Ranked #3 of 12 lakes in Litchfield County
Nearby Lakes in Litchfield County
Frequently asked questions about East Twin Lake
Where is East Twin Lake?
- East Twin Lake is a lake in Litchfield County, Connecticut. LakeQuality grades it B for nutrients and algae. The letter is not a swimming clearance.
What is the water quality grade for East Twin Lake?
- East Twin Lake in Litchfield County, Connecticut has a water quality grade of B (Good). Phosphorus: 10 µg/L. Chlorophyll-a (algae): 2.4 µg/L.
Is East Twin Lake safe to swim in?
- Good for swimming, clear water with low algae levels. East Twin Lake has a water quality grade of B (Good). Algae concentration (chlorophyll-a) is 2.4 µg/L. Always check local health department advisories before swimming.
Explore East Twin Lake across LakeGrade
More Connecticut Lake Rankings
Other Grade B Lakes in Connecticut
Oligotrophic 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.