John Martin Reservoir is a productive, nutrient-rich eutrophic lake in Bent County, Colorado. Water quality is graded F based on 1 sampling years through 2023.
Source: EPA Water Quality Portal sampling records, Colorado DNR, last sampled 2023-08-08. Grade methodology: LakeGrade methodology.
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Swimming Safety
Avoid swimming, very poor water quality, potential algae toxins
Water Quality Grade: F, Very Poor
Very murky, less than 3.1 ft of visibility. Trophic State Index: 61.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 3.1 ft | F |
| Phosphorus | No data | |
| Chlorophyll-a (Algae) | No data | |
| Trophic State Index (TSI) | 61 | Eutrophic |
High nutrients, frequent algae, reduced clarity
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Fishing John Martin Reservoir
Location
County Ranking
Ranked #1 of 1 lakes in Bent County
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More records, surveys & data sources
Data Sources
Water quality data from the EPA Water Quality Portal
Grading methodology based on Metropolitan Council standards
Most recent sample: 2023-08-08
Monitoring stations: 1