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LakeQuality

Main Section Lake

Clinton County, New YorkView mapDirections

NY DEC publishes the water-quality measurements for Main Section Lake. Here is what has been measured.

Clarity
14.8 ft
Typical for New York
Secchi · sampled 2024
Phosphorus
12.1 µg/L
Typical for New York
Measured by NY DEC
Chlorophyll-a
4.7 µg/L
Typical for New York
Measured by NY DEC
Water temp
~58°F
Typical for Oct · EPA WQP
Type
Mesotrophic
Trophic class
Trend
Worsening
5 years of samples
  • Mesotrophic
  • Impaired · Mercury
  • Public access

Main Section Lake in Clinton County, New York has water-quality measurements published by NY DEC, shown here as reported. Water clarity: 14.8 ft visibility. Phosphorus: 12.1 µg/L. Chlorophyll-a (algae): 4.7 µg/L.

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Main Section Lake is a mesotrophic lake in Clinton County, New York. Overall water quality is declining over recent sampling years. Limited fish-species data available. Public access is available with 2 public boat landings. Compared to the 2 other monitored lakes in Clinton County, Main Section Lake ranks #3 for water quality.

Source: EPA Water Quality Portal sampling records, NYSDEC, last sampled 2024-10-25. Methodology: how these readings are compared.

What Main Section Lake is good for

From access and monitoring records, not editorial picks.

  • Clear water14.8 ft of visibility
  • Boat launch2 documented ramps

Swimming conditions

Readings only

Moderate algae

Based on clarity and algae readings from past sampling — there is no live water temperature and a current cyanobacteria reading for this lake. Check your state or county health department before you swim.

Nutrient and algae readings are not a swimming clearance. Main Section Lake is listed impaired under Clean Water Act §303(d) (IR 5) for mercury, nutrients (phosphorus, nitrogen), pCBs. Check local advisories before you swim.

Whether Main Section Lake is safe to swim in today is a call for the New York Department of Environmental Conservation and the county health department, who post current advisories. LakeQuality does not issue swimming clearances.

Get alerts for Main Section Lake →

Water quality measurements for Main Section Lake

These are the measurements NY DEC publishes for Main Section Lake, shown as reported. The condition class beside each reading is the EPA National Lakes Assessment class for this lake’s ecoregion.

Good clarity, visible to about 14.8 ft. Phosphorus 12.1 µg/L. Chlorophyll-a 4.7 µg/L. TSI 41.

Water quality readings
MeasureReadingWhere it sits
Water clarity (Secchi depth)14.8ftMeasured, not scored

How deep a black-and-white disk stays visible from the surface. Higher is clearer.

Total phosphorus12.1µg/LGood
GoodFairPoor
Chlorophyll-a (algae)4.7µg/LFair
GoodFairPoor
Trophic state (TSI)Carlson's 0–100 index of how much algae a lake can support, from clarity, phosphorus and chlorophyll-a.41Mesotrophic
OligotrophicMesotrophicEutrophicHypereutrophic

Moderate nutrients, good water quality

Ask about Main Section Lake

Answers come straight from the public measurements and survey records on this page.

Water Temperature

Main Section Lake typically sits around 58°F at the surface in October. Summer average is about 67°F. Usually warmest in Aug (about 72°F) and coldest in Apr (about 43°F). These are typical values by month — not a live reading.

Jan
Feb
Mar
43°
Apr
49°
May
59°
Jun
70°
Jul
72°
Aug
66°
Sep
58°
Oct
Nov
Dec

Column height runs from this lake’s coldest month (43°F) to its warmest (72°F).

Typical surface water temperature by month, from 2,906 field readings (2010–2023) via the EPA Water Quality Portal. See the full Main Section Lake water temperature breakdown →

Recreation & Access

2
Boat Landings
Yes
Public Access
  • PeruPublic
  • Peace Point ParkPublic

Named access points in the USGS National Boat Ramps inventory, within about 3 miles. More lakes with boat ramps

Stays via Stay22

Stays near Main Section Lake

Compare lakeside cabins, hotels, and vacation rentals near Main Section Lake in Clinton County, New York — 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 Main Section Lake

Prices for Oct 23–25, 4 adults. Change dates on the map below.

Availability and prices from Stay22 partners (Booking.com, Vrbo, Expedia). We may earn a commission from bookings, at no extra cost to you.

Planning a trip? Cabins and lodging at Main Section Lake → · more New York lake trips

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Fishing Main Section Lake

Based on 5 years of monitoring (2020–2024).

  • Water clarity

    Worsening

    4 years

  • Phosphorus

    Stable

    -0.01 µg/L/yr5 years

  • Chlorophyll-a

    Stable

    -0.05 µg/L/yr3 years

See year-by-year chart →

EPA Impairment Status

Main Section Lake is officially listed as impaired under Clean Water Act §303(d) in the 2022 EPA reporting cycle (IR category 5).

Causes of impairment

MercuryNutrients (phosphorus, nitrogen)PCBs

Designated uses not supporting: Aquatic life.

A Total Maximum Daily Load (TMDL) plan has been approved.

Source: EPA ATTAINS assessment unit NY1001-0001 · Official waterbody report

Regulated Pollution Sources Nearby

7 EPA-permitted facilities operate within about 5 miles of Main Section Lake under Clean Water Act (NPDES) discharge permits, including 1 classified by the EPA as major discharger. 2 facilities have a reported Clean Water Act violation in the past three years.

  • Plattsburgh Water Pollution Control Plant
    Plattsburgh · 1.4 mi away · NPDES NY0026018
    MajorRecent violation
  • Country Sky Mobile Home Park
    Beekmantown · 3.7 mi away · NPDES NY0240133
    Recent violation
  • Champlain Park Sd Wwtp
    Plattsburgh · 1.1 mi away · NPDES NY0020834
  • Plattsburgh Coal Tar Confineme
    Plattsburgh · 1.8 mi away · NPDES NY0183628
  • Plattsburgh Intern'Al Airport
    Plattsburgh · 3.4 mi away · NPDES NY0217905
  • Dr Palmer Veterinary Clinic
    Plattsburgh · 3.5 mi away · NPDES NY0230901

Facilities permitted to discharge under the Clean Water Act within ~5 miles; proximity does not by itself mean a facility affects this lake. Source: EPA ECHO (ICIS-NPDES), as of 2026-07.

Nearby Lakes in Clinton County

Frequently asked questions about Main Section Lake

Where is Main Section Lake?

Main Section Lake is a lake in Clinton County, New York. Its water-quality measurements are published by NY DEC and shown on this page as reported.

What is the water quality of Main Section Lake?

Main Section Lake in Clinton County, New York has water-quality measurements published by NY DEC, shown here as reported. Water clarity: 14.8 ft visibility. Phosphorus: 12.1 µg/L. Chlorophyll-a (algae): 4.7 µg/L.

Measurements on this page ↑

Is Main Section Lake safe to swim in?

Nutrient and algae readings are not a swimming clearance. Main Section Lake is listed impaired under Clean Water Act §303(d) (IR 5) for mercury, nutrients (phosphorus, nitrogen), pCBs. Check local advisories before you swim.

Swimming on this page ↑

What is the water temperature of Main Section Lake?

Main Section Lake typically sits around 58°F at the surface in October, from 2,906 EPA Water Quality Portal field readings (2010–2023). That is a typical value for the month, not a live reading.

Temp on this page ↑

Are there boat ramps on Main Section Lake?

Main Section Lake has 2 documented boat landings in the USGS National Boat Ramps inventory. Named access points include Peru, Peace Point Park. Public access is listed as yes.

Access on this page ↑

Can I fish at Main Section Lake?

Main Section Lake has 2 documented boat landings in the USGS National Boat Ramps inventory. Seasons, size and bag limits, and whether you need a license are set by New York's fish and wildlife agency, so check its current regulations before you go.

Access on this page ↑

Where this data comes from

211 measurements from 1 monitoring station, 2020–2024. Retrieved from the EPA Water Quality Portal on 2026-08-02.

Collected and reported by

  • Vermont Dept of Environmental Conservation1VTDECWQ211 samples · 2020–2024

Analytical methods

  • EPA approved Alternate Test Procedure for 4500 P H. Has a 28 day hold without acid preservation.
  • 445.0 ~ EPA; Chlorophyll and Pheophytin in Algae by Fluorescence
Monitoring station identifiers (1)

EPA condition classes from the National Lakes Assessment (EPA 841-R-24-006, Table 6-3), applied by ecoregion. See where the data comes from and data sources.

Other records on this page

Impairment status from EPA ATTAINS 303(d) database

Regulated discharger data from EPA ECHO (ICIS-NPDES)

Named boat-access points from the USGS National Boat Ramps inventory