Middlesex County Lake Quality
Connecticut, 9 lakes, measured by CT DEEP
Middlesex County has 9 monitored lakes — a thin enough sample that one or two stressed lakes can move the county average noticeably. Use the per-lake pages below for what actually matters. 5 of those lakes carry recent nutrient and algae readings. The county-level summary describes that subset, not every water body listed. For Middlesex County the spread behind the average matters more than the average itself: a few nutrient-rich lakes among many clear ones produce the same figure as the inverse.
Most of the county's monitored lakes are shallow, under 50 feet, which means wind keeps the water column mixed all summer and sediment-bound phosphorus releases back into the surface layer whenever the bottom is disturbed. Bashan Lake has the lowest nutrient and algae readings in the county.
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Quick Answers for Middlesex County
Planning a trip? Check special fishing regulations for Bashan Lake — or check the official Connecticut fishing regulations.
All Lakes in Middlesex County
9 lakes · 5 ranked on readings, 4 without enough sampling5 lakes ranked on readings · 4 without enough sampling, hidden
| # | Lake | Clarity | Phosphorus | Algae | Trophic | Access |
|---|---|---|---|---|---|---|
| 1 | Bashan LakeMiddlesex | No recent samples | 15 µg/L | 1.5 µg/L | No recent samples | ✓ Public |
| 2 | Lake HaywardMiddlesex | No recent samples | 16 µg/L | 4.5 µg/L | No recent samples | ✓ Public |
| 3 | Pattaconk ReservoirMiddlesex | No recent samples | 16 µg/L | 2.8 µg/L | No recent samples | Not recorded |
| 4 | Black PondMiddlesex | No recent samples | 18 µg/L | 3.6 µg/L | No recent samples | ✓ Public |
| 5 | Lake BeseckMiddlesex | No recent samples | 46 µg/L | 31.7 µg/L | No recent samples | ✓ Public |
| Beseck LakeMiddlesex | 4.1 ft | No recent samples | No recent samples | No recent samples | Not recorded | |
| Cedar LakeMiddlesex | No recent samples | No recent samples | No recent samples | No recent samples | ✓ Public | |
| Pameacha PondMiddlesex | 1.3 ft | No recent samples | No recent samples | No recent samples | ✓ Public | |
| Unk LakeMiddlesex | No recent samples | 28 µg/L | 13.6 µg/L | No recent samples | Not recorded |
NR = no nutrient or algae reading on record. The measurements are published as the authority reports them. Where the data comes from.
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Source: the Connecticut Department of Energy and Environmental Protection. See data sources.