Hopatcong A Lake
Hopatcong A Lake in Sussex County, New Jersey is not rated for water quality — its monitoring record does not meet the evidence bar. Water clarity: 4.3 ft visibility.
- Clarity
- 4.3 ft
Why Hopatcong A 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 Hopatcong A Lake, the only measurement available is water clarity, which is not a water-quality indicator on its own — EPA's National Lakes Assessment does not grade clarity. 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.
Hopatcong A Lake is a lake in Sussex County, New Jersey.
Source: EPA Water Quality Portal sampling records, your state environmental agency, last sampled 2025-09-24. 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 Hopatcong A Lake
These readings exist but do not meet the evidence bar for an A–F grade — see why.
Murky, only visible to about 4.3 ft. Trophic State Index: 56.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 4.3 ft | Not graded |
| Phosphorus | No recent samples | |
| Chlorophyll-a (Algae) | No recent samples | |
| Trophic State Index (TSI) | 56 | Eutrophic |
High nutrients, frequent algae, reduced clarity
Where to stay near Hopatcong A Lake
Compare lakeside cabins, hotels, and vacation rentals near Hopatcong A Lake in Sussex County, New Jersey — 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 Hopatcong A Lake
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Fishing Hopatcong A Lake
EPA Impairment Status
Hopatcong A Lake is officially listed as impaired under Clean Water Act §303(d) in the 2022 EPA reporting cycle (IR category 5).
Causes of impairment
A Total Maximum Daily Load (TMDL) plan has been approved.
Source: EPA ATTAINS assessment unit NJ02040105150020-01 · Official waterbody report · Matched by proximity (2.25 km)
Graded lakes near Hopatcong A Lake
Hopatcong A Lake has no grade, but these lakes within a short drive do.
Nearby Lakes in Sussex County
Frequently asked questions about Hopatcong A Lake
Where is Hopatcong A Lake?
- Hopatcong A Lake is a lake in Sussex County, New Jersey. LakeQuality has not rated this lake (UNRATED) — there is not enough recent sampling to assign a letter.
What is the water quality grade for Hopatcong A Lake?
- Hopatcong A Lake in Sussex County, New Jersey is not rated for water quality — its monitoring record does not meet the evidence bar. Water clarity: 4.3 ft visibility.
Is Hopatcong A Lake safe to swim in?
- Not rated for swimming — there is not enough monitoring data to judge this lake. Hopatcong A 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 Hopatcong A Lake across LakeGrade
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Eutrophic Lakes in New Jersey
Where this data comes from
43 measurements from 7 monitoring stations, 2024–2025. Retrieved from the EPA Water Quality Portal on 2026-08-21.
Collected and reported by
- Princeton Hydro LLC
PRINCETONHYDRO43 samples · 2024–2025
Monitoring station identifiers (7)
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.
Other records on this page
Impairment status from EPA ATTAINS 303(d) database