Washington County Lake Quality
Oklahoma, 3 lakes, measured by Oklahoma DEQ
Washington County has 3 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. 1 of those lake carry recent nutrient and algae readings. The county-level summary describes that subset, not every water body listed. Phosphorus and algae readings vary widely across Washington County; the per-lake pages below carry the numbers.
The county's lakes lean shallow, which makes the readings sensitive to wind, sediment-resuspension, and any nutrient inputs from the watershed. The cleanest measured lake is Copan Lake.
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Quick Answers for Washington County
Planning a trip? Check special fishing regulations for Copan Lake — or check the official Oklahoma fishing regulations.
All Lakes in Washington County
3 lakes · 1 ranked on readings, 2 without enough sampling1 lake ranked on readings · 2 without enough sampling, hidden
| # | Lake | Clarity | Phosphorus | Algae | Trophic | Access |
|---|---|---|---|---|---|---|
| 1 | Copan LakeWashington | 1.6 ft | 79 µg/L | No recent samples | No recent samples | ✓ Public |
| Youngs LakeWashington | No recent samples | No recent samples | No recent samples | No recent samples | Not recorded | |
| Long LakeWashington | 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 Oklahoma Department of Environmental Quality. See data sources.