Putnam County, Ohio · Water Quality Report Card
Ottawa Reservoir
Ottawa Reservoir in Putnam County, Ohio has a water quality grade of D (Poor). Phosphorus: 74.9 µg/L.
- Type
- Eutrophic
Ottawa Reservoir is a productive, nutrient-rich eutrophic lake in Putnam County, Ohio. Water quality is graded D based on 1 sampling years through 2024.
Source: EPA Water Quality Portal sampling records, Ohio EPA, last sampled 2024-09-18. Grade methodology: LakeGrade methodology.
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Swimming Safety
Swimming not recommended, poor water quality with high algae risk
Water Quality Grade: D (Poor)
No clarity data. Phosphorus level: 74.9 µg/L. Trophic State Index: 66.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | No data | |
| Phosphorus | 74.9 µg/L | Poor |
| Chlorophyll-a (Algae) | No data | |
| Trophic State Index (TSI) | 66 | Eutrophic |
High nutrients, frequent algae, reduced clarity
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Fishing Ottawa Reservoir
Location
County Ranking
Ranked #1 of 1 lakes in Putnam County
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More records, surveys & data sources
Where this data comes from
10 measurements from 1 monitoring station, 2024. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- Division of Surface water (Ohio)
21OHIO_WQX10 samples · 2024
Analytical methods
- Total Phosphorus After Block Digestion
Monitoring station identifiers (1)
Grade thresholds come from the U.S. EPA National Lakes Assessment 2022 Technical Support Document (EPA 841-R-24-006, Table 6-3), applied by ecoregion. See how grades are calculated.
Data Sources
Water quality data from the EPA Water Quality Portal
Grade thresholds from the EPA National Lakes Assessment (EPA 841-R-24-006, Table 6-3), applied by ecoregion
Most recent sample: 2024-09-18
Monitoring stations: 1