Halfmoon Pond-Deep Spot
Halfmoon Pond-Deep Spot in Sullivan County, New Hampshire is not rated for water quality — its monitoring record does not meet the evidence bar. Phosphorus: 14.6 µg/L.
- Public access
- Yes
Why Halfmoon Pond-Deep Spot 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 Halfmoon Pond-Deep Spot, no nutrient or algae measurement meets the evidence bar (at least 3 samples within 10 years). Sampling here has recorded phosphorus, but not water clarity 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.
Halfmoon Pond-Deep Spot is a lake in Sullivan County, New Hampshire. Limited fish-species data available. Public access is available with 1 public boat landing.
Source: EPA Water Quality Portal sampling records, your state environmental agency, last sampled 2024-07-23. Grade methodology: LakeGrade methodology.
Watch Halfmoon Pond-Deep Spot water quality
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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 Halfmoon Pond-Deep Spot
These readings exist but do not meet the evidence bar for an A–F grade — see why.
No clarity data. Phosphorus level: 14.6 µg/L. Trophic State Index: 43.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | No recent samples | |
| Phosphorus | 14.6 µg/L | Not graded |
| Chlorophyll-a (Algae) | No recent samples | |
| Trophic State Index (TSI) | 43 | Mesotrophic |
Moderate nutrients, good water quality
Where to stay near Halfmoon Pond-Deep Spot
Compare lakeside cabins, hotels, and vacation rentals near Halfmoon Pond-Deep Spot in Sullivan County, New Hampshire — 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 Halfmoon Pond-Deep Spot
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Recreation & Access
- Halfmoon PondPublic
Named access points from the USGS National Boat Ramps inventory, snapped within 5 km. More lakes with boat ramps
Fishing Halfmoon Pond-Deep Spot
EPA Impairment Status
Halfmoon Pond-Deep Spot is officially listed as impaired under Clean Water Act §303(d) in the 2024 EPA reporting cycle (IR category 5).
Causes of impairment
A Total Maximum Daily Load (TMDL) plan has been approved.
Source: EPA ATTAINS assessment unit NHLAK700030201-02 · Official waterbody report · Matched by proximity (0.34 km)
Graded lakes near Halfmoon Pond-Deep Spot
Halfmoon Pond-Deep Spot has no grade, but these lakes within a short drive do.
Nearby Lakes in Sullivan County
Frequently asked questions about Halfmoon Pond-Deep Spot
Where is Halfmoon Pond-Deep Spot?
- Halfmoon Pond-Deep Spot is a lake in Sullivan County, New Hampshire. LakeQuality has not rated this lake (UNRATED) — there is not enough recent sampling to assign a letter.
What is the water quality grade for Halfmoon Pond-Deep Spot?
- Halfmoon Pond-Deep Spot in Sullivan County, New Hampshire is not rated for water quality — its monitoring record does not meet the evidence bar. Phosphorus: 14.6 µg/L.
Is Halfmoon Pond-Deep Spot safe to swim in?
- Not rated for swimming — there is not enough monitoring data to judge this lake. Halfmoon Pond-Deep Spot is not rated for water quality — its monitoring record does not meet the evidence bar. Always check local health department advisories before swimming.
Are there boat ramps on Halfmoon Pond-Deep Spot?
- Halfmoon Pond-Deep Spot has 1 documented boat landing in the USGS National Boat Ramps inventory. Named access points include Halfmoon Pond. Public access is listed as yes.
Explore Halfmoon Pond-Deep Spot across LakeGrade
More New Hampshire Lake Rankings
Top 25 by overall water quality score
Top 25 by Secchi water clarity
Grade A/B + low algae filter
Panfish-rich, public access
Full state directory
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Where this data comes from
2 measurements from 1 monitoring station, 2024. Retrieved from the EPA Water Quality Portal on 2026-08-21.
Collected and reported by
- New Hampshire Department Of Environmental Services (BEACH)
111133002 samples · 2024
Analytical methods
- 10-115-01-1 F ~ LACHAT; Total Phosphorus- Manual persulfate digest
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.
Other records on this page
Impairment status from EPA ATTAINS 303(d) database
Named boat-access points from the USGS National Boat Ramps inventory