Jackson County Lake Quality
Colorado, 4 lakes, average grade B (Good)
Jackson County has 4 graded 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 county-wide average lands at B — solid water quality with most lakes carrying clear summer transparency and low-to-moderate phosphorus.
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. Seven Lakes (A) is the cleanest in the county.
Quick Answers for Jackson County
Planning a trip? Check special fishing regulations for Seven Lakes — or check the official Colorado fishing regulations.
All Lakes in Jackson County
| Rank | Lake | Grade | Clarity | Phosphorus |
|---|---|---|---|---|
| 1 | Seven Lakes | A | - | 10.5 µg/L |
| 2 | Summit Lake | B | 12.1 ft | 20 µg/L |
| 3 | Lake John | B | 13.8 ft | - |
| 4 | North Delaney Lake | C | 8.2 ft | - |
Other Counties in Colorado
See how Jackson County stacks up in the national county water-quality rankings, or browse the full directory of graded lakes across all 12 states.
Where to stay near Jackson County
Top-rated places to stay near Jackson County
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Source: EPA National Aquatic Resource Surveys, 2026.