L. Champlain Lake
Addison County, VermontView mapDirections
Vermont DEC publishes the water-quality measurements for L. Champlain Lake. Here is what has been measured.
- Impaired · Mercury
- Public access
- Limited data
L. Champlain Lake in Addison County, Vermont has water-quality measurements published by Vermont DEC, shown here as reported. Phosphorus: 26.1 µg/L. Chlorophyll-a (algae): 4 µg/L.
L. Champlain Lake is a lake in Addison County, Vermont. Limited fish-species data available. Public access is available with 1 public boat landing.
Source: EPA Water Quality Portal sampling records, VT DEC, last sampled 2025-08-21. Methodology: how these readings are compared.
What L. Champlain Lake is good for
From access and monitoring records, not editorial picks.
- Boat launch1 documented ramp
Swimming conditions
No readingRecreation use not supported
Nutrient and algae readings are not a swimming clearance. L. Champlain Lake is listed impaired under Clean Water Act §303(d) (IR 5) for mercury, nuisance exotic species, nutrients (phosphorus, nitrogen), pCBs. Check local advisories before you swim.
Whether L. Champlain Lake is safe to swim in today is a call for the Vermont Department of Environmental Conservation and the county health department, who post current advisories. LakeQuality does not issue swimming clearances.
Water quality measurements for L. Champlain Lake
These are the measurements Vermont DEC publishes for L. Champlain Lake, shown as reported. The condition class beside each reading is the EPA National Lakes Assessment class for this lake’s ecoregion.
No clarity data. Phosphorus 26.1 µg/L. Chlorophyll-a 4 µg/L. TSI 48.
| Measure | Reading | Where it sits |
|---|---|---|
| Water clarity (Secchi depth) | No reading How deep a black-and-white disk stays visible from the surface. Higher is clearer. | |
| Total phosphorus | 26.1µg/L | Measured, not scored The nutrient that most limits algae growth in freshwater. More phosphorus, more algae potential. |
| Chlorophyll-a (algae) | 4µg/L | Measured, not scored The green pigment in algae — a direct measure of how much algae is in the water. |
| Trophic state (TSI)Carlson's 0–100 index of how much algae a lake can support, from clarity, phosphorus and chlorophyll-a. | 48 | Mesotrophic OligotrophicMesotrophicEutrophicHypereutrophic |
Moderate nutrients, good water quality
Ask about L. Champlain Lake
Answers come straight from the public measurements and survey records on this page.
Recreation & Access
- WestportPublic
Named access points in the USGS National Boat Ramps inventory, within about 3 miles. More lakes with boat ramps
Stays via Stay22
Stays near L. Champlain Lake
Compare lakeside cabins, hotels, and vacation rentals near L. Champlain Lake in Addison County, Vermont — 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 L. Champlain Lake
Prices for Oct 30–Nov 1, 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 L. Champlain Lake → · more Vermont lake trips
Follow L. Champlain Lake’s readings
Email me when new measurements post for this lake. Updates stay free.
Or email
Fishing L. Champlain Lake
EPA Impairment Status
L. Champlain Lake is officially listed as impaired under Clean Water Act §303(d) in the 2022 EPA reporting cycle (IR category 5).
Causes of impairment
Designated uses not supporting: Drinking water, Aquatic life, Fish consumption, Recreation, Other.
A Total Maximum Daily Load (TMDL) plan has been approved.
Source: EPA ATTAINS assessment unit VT04-01L02_02 · Official waterbody report
Nearby Lakes in Addison County
Frequently asked questions about L. Champlain Lake
Where is L. Champlain Lake?
- L. Champlain Lake is a lake in Addison County, Vermont. Its water-quality measurements are published by Vermont DEC and shown on this page as reported.
What is the water quality of L. Champlain Lake?
- L. Champlain Lake in Addison County, Vermont has water-quality measurements published by Vermont DEC, shown here as reported. Phosphorus: 26.1 µg/L. Chlorophyll-a (algae): 4 µg/L.
Is L. Champlain Lake safe to swim in?
- Nutrient and algae readings are not a swimming clearance. L. Champlain Lake is listed impaired under Clean Water Act §303(d) (IR 5) for mercury, nuisance exotic species, nutrients (phosphorus, nitrogen), pCBs. Check local advisories before you swim.
Are there boat ramps on L. Champlain Lake?
- L. Champlain Lake has 1 documented boat landing in the USGS National Boat Ramps inventory. Named access points include Westport. Public access is listed as yes.
Can I fish at L. Champlain Lake?
- L. Champlain Lake has 1 documented boat landing in the USGS National Boat Ramps inventory. Seasons, size and bag limits, and whether you need a license are set by Vermont's fish and wildlife agency, so check its current regulations before you go.
Explore L. Champlain Lake across LakeQuality
More lakes in Vermont
Other Lakes in Vermont
Mesotrophic Lakes in Vermont
Where this data comes from
4 measurements from 1 monitoring station, 2025. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- Vermont Dept of Environmental Conservation
1VTDECWQ4 samples · 2025
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
Named boat-access points from the USGS National Boat Ramps inventory