Silver Lake-Deep Spot
Silver Lake-Deep Spot in Hillsborough County, New Hampshire has a water quality grade of B (Good). Phosphorus: 11.4 µg/L. Surface area: 34 acres.
- Area
- 34 acres
- Type
- Oligotrophic
- Public access
- Yes
Silver Lake-Deep Spot is a 34-acre cold, clear oligotrophic lake in Hillsborough County, New Hampshire. Water quality is graded B based on 1 sampling years through 2025. Limited fish-species data available. Public access is available with 1 public boat landing. Compared to the 35 other monitored lakes in Hillsborough County, Silver Lake-Deep Spot ranks #5 for water quality.
Source: EPA Water Quality Portal sampling records, your state environmental agency, last sampled 2025-08-03. Grade methodology: LakeGrade methodology.
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Swimming Safety
Grade onlyBacteria advisory
Based on clarity and algae grades from past sampling — we do not hold live water temperature and a current cyanobacteria reading for this lake. Check your state or county health department before you swim.
Good for swimming, clear water with low algae levels
Water Quality Grade: B (Good)
No clarity data. Phosphorus level: 11.4 µg/L. Trophic State Index: 39.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | No recent samples | |
| Phosphorus | 11.4 µg/L | Good |
| Chlorophyll-a (Algae) | No recent samples | |
| Trophic State Index (TSI) | 39 | Oligotrophic |
Low nutrients, clear water, excellent for swimming
Where to stay near Silver Lake-Deep Spot
Compare lakeside cabins, hotels, and vacation rentals near Silver Lake-Deep Spot in Hillsborough 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 Silver Lake-Deep Spot
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Lake Details
| Characteristic | Value |
|---|---|
| Surface Area | 34 acres |
| Public Access | Yes |
No bathymetric survey has been published for Silver Lake-Deep Spot, so its depth is not documented here.
Recreation & Access
- Flints PondPublic
Named access points from the USGS National Boat Ramps inventory, snapped within 5 km. More lakes with boat ramps
Fishing Silver Lake-Deep Spot
Reservoir Info (USACE NID)
Silver Lake-Deep Spot is a man-made reservoir impounded by the Silver Lake Dam (completed 1930), built primarily for recreation on the Pennichuck Brook; earth-type dam, 8 ft tall and 16.6 ft long.
- Surface area
- 34 ac
- Normal storage
- 90 ac-ft
- Max storage
- 120 ac-ft
- Drainage area
- 0.34 sq mi
- Hazard class
- Low
- Owner
- NH DNCR
Source: USACE National Inventory of Dams, NID ID NH01056 · Operator website · Matched by proximity (0.34 km)
EPA Impairment Status
Silver Lake-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 NHLAK700061001-02-01 · Official waterbody report · Matched by proximity (0.09 km)
County Ranking
Ranked #5 of 36 lakes in Hillsborough County
Nearby Lakes in Hillsborough County
Frequently asked questions about Silver Lake-Deep Spot
Where is Silver Lake-Deep Spot?
- Silver Lake-Deep Spot is a lake in Hillsborough County, New Hampshire. LakeQuality grades it B for nutrients and algae. The letter is not a swimming clearance.
What is the water quality grade for Silver Lake-Deep Spot?
- Silver Lake-Deep Spot in Hillsborough County, New Hampshire has a water quality grade of B (Good). Phosphorus: 11.4 µg/L. Surface area: 34 acres.
Is Silver Lake-Deep Spot safe to swim in?
- Good for swimming, clear water with low algae levels. Silver Lake-Deep Spot has a water quality grade of B (Good). Always check local health department advisories before swimming.
Are there boat ramps on Silver Lake-Deep Spot?
- Silver Lake-Deep Spot has 1 documented boat landing in the USGS National Boat Ramps inventory. Named access points include Flints Pond. Public access is listed as yes.
Explore Silver Lake-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
Other Grade B Lakes in New Hampshire
Oligotrophic Lakes in New Hampshire
Where this data comes from
21 measurements from 1 monitoring station, 2022–2025. Retrieved from the EPA Water Quality Portal on 2026-08-21.
Collected and reported by
- New Hampshire Department Of Environmental Services (BEACH)
1111330021 samples · 2022–2025
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