Grady County Lake Quality
Oklahoma, 2 lakes, average grade C (Fair)
Only 2 lakes in Grady 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. Grady 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. Nla Lake (B) is the cleanest in the county.
Quick Answers for Grady County
Planning a trip? Check special fishing regulations for Nla Lake — or check the official Oklahoma fishing regulations.
All Lakes in Grady County
| Rank | Lake | Grade | Clarity | Phosphorus |
|---|---|---|---|---|
| 1 | Nla Lake | B | 8.9 ft | 17.8 µg/L |
| 2 | Nla Lake | C | 6.5 ft | 2506.5 µg/L |
Other Counties in Oklahoma
See how Grady 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 Grady County
Top-rated places to stay near Grady 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 Grady County?
Get lake water-quality report cards plus the best cabin & lodging deals near Grady County — straight to your inbox. No spam, unsubscribe anytime.
Source: EPA National Aquatic Resource Surveys, 2026.