Diamond Lake
Diamond Lake in Hartford County, Connecticut is not rated for water quality — its monitoring record does not meet the evidence bar. Water clarity: 6.6 ft visibility.
- Clarity
- 6.6 ft
Why Diamond Lake has no grade
We grade a lake only when its monitoring record clears the evidence bar: at least three phosphorus or chlorophyll-a samples in the last ten years, scored against EPA National Lakes Assessment thresholds for this lake’s ecoregion. For Diamond Lake, no nutrient or algae measurement meets the evidence bar (at least 3 samples within 10 years). Sampling here has recorded water clarity, but not phosphorus and algae (chlorophyll-a).
Not Rated is not an F. It is EPA Integrated Reporting Category 3 — insufficient information. The water here may be excellent or poor; nobody has measured enough of it to say. Everything below that has been measured is still reported on this page.
Sampling is run by your state environmental agency and volunteer programs, and published through the EPA Water Quality Portal. Read the full grading methodology.
Diamond Lake is a lake in Hartford County, Connecticut.
Source: EPA Water Quality Portal sampling records, your state environmental agency, last sampled 2020-07-16. Grade methodology: LakeGrade methodology.
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Swimming Safety
Not ratedLimited data
Not rated for swimming — there is not enough monitoring data to judge this lake
Water quality measurements for Diamond Lake
These readings exist but do not meet the evidence bar for an A–F grade — see why.
Murky, only visible to about 6.6 ft. Trophic State Index: 50.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 6.6 ft | Not graded |
| Phosphorus | No recent samples | |
| Chlorophyll-a (Algae) | No recent samples | |
| Trophic State Index (TSI) | 50 | Eutrophic |
High nutrients, frequent algae, reduced clarity
Where to stay near Diamond Lake
Compare lakeside cabins, hotels, and vacation rentals near Diamond Lake in Hartford County, Connecticut — live availability and prices for your trip. Switch the map to Satellite to see the lake and how close each stay is to the water.
Top-rated places to stay near Diamond Lake
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Fishing Diamond Lake
Graded lakes near Diamond Lake
Diamond Lake has no grade, but these lakes within a short drive do.
Nearby Lakes in Hartford County
Frequently asked questions about Diamond Lake
Where is Diamond Lake?
- Diamond Lake is a lake in Hartford County, Connecticut. LakeQuality has not rated this lake (UNRATED) — there is not enough recent sampling to assign a letter.
What is the water quality grade for Diamond Lake?
- Diamond Lake in Hartford County, Connecticut is not rated for water quality — its monitoring record does not meet the evidence bar. Water clarity: 6.6 ft visibility.
Is Diamond Lake safe to swim in?
- Not rated for swimming — there is not enough monitoring data to judge this lake. Diamond Lake is not rated for water quality — its monitoring record does not meet the evidence bar. Always check local health department advisories before swimming.
Explore Diamond Lake across LakeGrade
More Connecticut Lake Rankings
Other Lakes in Connecticut
Eutrophic Lakes in Connecticut
Where this data comes from
1 measurement from 1 monitoring station, 2020. Retrieved from the EPA Water Quality Portal on 2026-08-21.
Collected and reported by
- North American Lake Management Society
NALMS1 sample · 2020
Monitoring station identifiers (1)
Grade thresholds from the EPA National Lakes Assessment (EPA 841-R-24-006, Table 6-3), applied by ecoregion. See how grades are calculated and data sources.