Grundy County Lake Quality
Illinois, 4 lakes, measured by Illinois EPA
Grundy County has 4 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. The 4 monitored lakes in Grundy County carry whatever clarity, phosphorus, and chlorophyll-a readings Illinois EPA has published, shown as reported.
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.
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Quick Answers for Grundy County
Planning a trip? Check special fishing regulations for Heidecke Lake — or check the official Illinois fishing regulations.
All Lakes in Grundy County
4 lakes · 0 ranked on readings, 4 without enough sampling0 lakes ranked on readings · 4 without enough sampling, hidden
| # | Lake | Clarity | Phosphorus | Algae | Trophic | Max Depth | Access |
|---|---|---|---|---|---|---|---|
| Heidecke LakeGrundy | No recent samples | No recent samples | No recent samples | No recent samples | 59.1 ft | ✓ Public | |
| Negro SloughGrundy | No recent samples | No recent samples | No recent samples | No recent samples | No recent samples | Not recorded | |
| Dresden Cooling LakeGrundy | No recent samples | No recent samples | No recent samples | No recent samples | 16 ft | Not recorded | |
| Goose LakeGrundy | No recent samples | No recent samples | No recent samples | No recent samples | 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 Illinois Environmental Protection Agency. See data sources.