Osage County Lake Quality
Kansas, 6 lakes, average grade C (Fair)
Only 6 lakes in Osage 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. Osage 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. Osage Co State Fishing Lake (B) is the cleanest in the county.
Quick Answers for Osage County
Planning a trip? Check special fishing regulations for Osage Co State Fishing Lake — or check the official Kansas fishing regulations.
All Lakes in Osage County
| Rank | Lake | Grade | Clarity | Phosphorus |
|---|---|---|---|---|
| 1 | Osage Co State Fishing Lake | B | 6.2 ft | - |
| 2 | Melvern Lake | B | 4.8 ft | 21 µg/L |
| 3 | Strowbridge Reservoir | C | 2.4 ft | 24 µg/L |
| 4 | Nla Lake | D | 1 ft | 118.2 µg/L |
| 5 | Pomona Lake | D | 2.9 ft | 67 µg/L |
| 6 | Carbondale West Lake | F | 0.6 ft | - |
Other Counties in Kansas
See how Osage County stacks up in the national county water-quality rankings, or browse the full directory of graded lakes across all 34 states.
Where to stay near Osage County
Top-rated places to stay near Osage 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 Osage County?
Get lake water-quality report cards plus the best cabin & lodging deals near Osage County — straight to your inbox. No spam, unsubscribe anytime.
Source: EPA National Aquatic Resource Surveys, 2026.