
Union County Lake Quality
New Jersey, 2 lakes, measured by NJDEP
Union County holds 2 monitored lakes. With a sample that small the county-level summary describes those specific waters, not necessarily every water body in the county. Every one of those lakes carries recent nutrient and algae readings, so the county-level summary covers the full set rather than a monitored subset. Most monitored lakes in Union County are productive, shallow basins; each lake page shows its own phosphorus and chlorophyll-a readings beside the EPA condition class.
The county's lakes lean shallow, which makes the readings sensitive to wind, sediment-resuspension, and any nutrient inputs from the watershed. The cleanest measured lake is Echo Lake.
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Quick Answers for Union County
Planning a trip? Check special fishing regulations for Echo Lake — or check the official New Jersey fishing regulations.
All Lakes in Union County
2 lakes2 lakes ranked on readings
| # | Lake | Clarity | Phosphorus | Algae | Trophic | Access |
|---|---|---|---|---|---|---|
| 1 | Echo LakeUnion | 2.8 ft | 115.5 µg/L | 19.5 µg/L | No recent samples | Not recorded |
| 2 | Middlesex ReservoirUnion | 3.6 ft | 173 µg/L | 11.3 µg/L | No recent samples | Not recorded |
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Source: the New Jersey Department of Environmental Protection. See data sources.