Washington County Lake Quality
Oregon, 3 lakes, measured by Oregon DEQ
Washington County holds 3 monitored lakes. With a sample that small the county-level summary describes those specific waters, not necessarily every water body in the county. 1 of those lake carry recent nutrient and algae readings. The county-level summary describes that subset, not every water body listed. Taken together, the monitored lakes of Washington County sit near the low-nutrient end of the Oregon range.
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. Henry Hagg Lake has the lowest nutrient and algae readings in the county.
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Quick Answers for Washington County
Planning a trip? Check special fishing regulations for Henry Hagg Lake — or check the official Oregon 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 | Henry Hagg LakeWashington | No recent samples | No recent samples | 1.5 µg/L | No recent samples | ✓ Public |
| Stimson MillpondWashington | No recent samples | No recent samples | No recent samples | No recent samples | Not recorded | |
| Barney ReservoirWashington | 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 Oregon Department of Environmental Quality. See data sources.