Brown County Lake Quality
Kansas, 6 lakes, average grade F (Very Poor)
Brown County has 6 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 average is F — the most-stressed bracket in our rubric. Most monitored lakes here show persistent nutrient loading and algal pressure.
The county's lakes lean shallow, which makes the grades sensitive to wind, sediment-resuspension, and any nutrient inputs from the watershed. The cleanest lake on the books is Mission Lake (D); the most-stressed is Hiawatha City Lake (F).
Quick Answers for Brown County
Planning a trip? Check special fishing regulations for Mission Lake — or check the official Kansas fishing regulations.
All Lakes in Brown County
| Rank | Lake | Grade | Clarity | Phosphorus |
|---|---|---|---|---|
| 1 | Mission Lake | D | 1 ft | 170 µg/L |
| 2 | Brown Co State Fishing Lake | D | 1.3 ft | 88 µg/L |
| 3 | Pony Creek Lake | D | 2.2 ft | 83 µg/L |
| 4 | Hiawatha City Lake | F | 2.1 ft | 135 µg/L |
| 5 | Little Lake | F | - | 250 µg/L |
Other Counties in Kansas
See how Brown 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 Brown County
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Source: EPA National Aquatic Resource Surveys, 2026.