Gloucester County Lake Quality
New Jersey, 4 lakes, average grade C (Fair)
Only 4 lakes in Gloucester County carry an active grade. The county-level summary is therefore representative of those specific lakes, not necessarily of every water body in the county. Gloucester County averages to a C. The distribution behind that average matters more than the letter: a few stressed lakes versus many decent ones can produce the same average 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. Grenloch Lake (A) is the cleanest in the county.
Where to stay near Gloucester County
Top-rated places to stay near Gloucester County
Availability and prices from Stay22 partners (Booking.com, Vrbo, Expedia). We may earn a commission from bookings, at no extra cost to you.
Planning a trip to Gloucester County?
Get lake water-quality report cards plus the best cabin & lodging deals near Gloucester County — straight to your inbox. No spam, unsubscribe anytime.
Quick Answers for Gloucester County
Planning a trip? Check special fishing regulations for Grenloch Lake — or check the official New Jersey fishing regulations.
All Lakes in Gloucester County
4 lakes · 3 graded, 1 not rated3 graded lakes · 1 not rated, hidden
| # | Lake | Grade | Clarity | Phosphorus | Algae | Trophic | Access |
|---|---|---|---|---|---|---|---|
| 1 | AGrenloch LakeGloucester | A | 4.8 ft | 30 µg/L | 4.3 µg/L | No recent samples | Not recorded |
| 2 | DAlmonesson LakeGloucester | D | 1.8 ft | 100 µg/L | 28.3 µg/L | No recent samples | Not recorded |
| 3 | DMalaga LakeGloucester | D | 3.6 ft | 110 µg/L | 29.2 µg/L | No recent samples | Not recorded |
| NRLake AlcyonGloucester | NR | 4.3 ft | No recent samples | No recent samples | No recent samples | Not recorded |
NR = not rated: the monitoring record does not meet the evidence bar for a grade. That is EPA Integrated Reporting Category 3 (insufficient information), not a failing grade. How grading works.
Lake Match
Which lake suits how you actually use one?
Six questions — swimming, fishing, quiet, cabins, drive time — and a shortlist of graded lakes that fit, with the water quality behind each one.
Other Counties in New Jersey
See how Gloucester County stacks up in the national county water-quality rankings, or browse the full directory of graded lakes across all 49 states and 2 Canadian provinces.
Source: EPA National Aquatic Resource Surveys, 2026.