Alexander Lake
Alexander Lake in Windham County, Connecticut has a water quality grade of C (Fair). Phosphorus: 27 µg/L. Chlorophyll-a (algae): 0.9 µg/L. Surface area: 31 acres.
- Area
- 31 acres
- Type
- Mesotrophic
Alexander Lake is a 31-acre mesotrophic lake in Windham County, Connecticut. Water quality is graded C based on 2 sampling years through 2024. Compared to the 2 other monitored lakes in Windham County, Alexander Lake ranks #1 for water quality.
Source: EPA Water Quality Portal sampling records, your state environmental agency, last sampled 2024-08-28. 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: 27 µg/L. Chlorophyll-a: 0.9 µg/L. Trophic State Index: 41.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | No recent samples | |
| Phosphorus | 27 µg/L | Fair |
| Chlorophyll-a (Algae) | 0.9 µg/L | Not graded |
| Trophic State Index (TSI) | 41 | Mesotrophic |
Moderate nutrients, good water quality
Where to stay near Alexander Lake
Compare lakeside cabins, hotels, and vacation rentals near Alexander Lake in Windham 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 Alexander Lake
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Lake Details
| Characteristic | Value |
|---|---|
| Surface Area | 31 acres |
No bathymetric survey has been published for Alexander Lake, so its depth is not documented here.
Fishing Alexander Lake
Reservoir Info (USACE NID)
Alexander Lake is a man-made reservoir impounded by the Dayville Dike (completed 1925), built primarily for hydroelectric on the Five Mile River; earth-type dam, 14 ft tall and 5,000 ft long.
- Surface area
- 31 ac
- Normal storage
- 93 ac-ft
- Max storage
- 93 ac-ft
- Drainage area
- 57 sq mi
- Hazard class
- Low
- Owner
- Summit Hydro, LLC
Source: USACE National Inventory of Dams, NID ID CT00169 · Operator website · Matched by proximity (0.94 km)
County Ranking
Ranked #1 of 3 lakes in Windham County
Nearby Lakes in Windham County
Frequently asked questions about Alexander Lake
Where is Alexander Lake?
- Alexander Lake is a lake in Windham County, Connecticut. LakeQuality grades it C for nutrients and algae. The letter is not a swimming clearance.
What is the water quality grade for Alexander Lake?
- Alexander Lake in Windham County, Connecticut has a water quality grade of C (Fair). Phosphorus: 27 µg/L. Chlorophyll-a (algae): 0.9 µg/L. Surface area: 31 acres.
Is Alexander Lake safe to swim in?
- Generally safe for swimming, moderate water quality. Alexander Lake has a water quality grade of C (Fair). Algae concentration (chlorophyll-a) is 0.9 µg/L. Always check local health department advisories before swimming.
Explore Alexander Lake across LakeGrade
More Connecticut Lake Rankings
Other Grade C Lakes in Connecticut
Mesotrophic Lakes in Connecticut
Where this data comes from
26 measurements from 1 monitoring station, 2024. Retrieved from the EPA Water Quality Portal on 2026-08-21.
Collected and reported by
- Connecticut Department Of Energy And Environmental Protection
CT_DEP01_WQX26 samples · 2024
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.