Lake Memphremagog
Orleans County, VermontView mapDirections
Vermont DEC publishes the water-quality measurements for Lake Memphremagog. Here is what has been measured.
- Mesotrophic
- Impaired · Hydrologic alteration
- 292 ft max depth
- Public access
Lake Memphremagog in Orleans County, Vermont has water-quality measurements published by Vermont DEC, shown here as reported. Water clarity: 10.5 ft visibility. Phosphorus: 16.4 µg/L. Chlorophyll-a (algae): 5.5 µg/L.
Lake Memphremagog is a mesotrophic lake in Orleans County, Vermont with an estimated average depth of about 292 feet. Water clarity is declining over recent sampling years. Limited fish-species data available. Public access is available with 2 public boat landings. Compared to the 16 other monitored lakes in Orleans County, Lake Memphremagog ranks #14 for water quality.
Source: EPA Water Quality Portal sampling records, VT DEC, last sampled 2025-08-19. Methodology: how these readings are compared.
What Lake Memphremagog is good for
From access and monitoring records, not editorial picks.
- Clear water10.5 ft of visibility
- Boat launch2 documented ramps
Swimming conditions
Readings onlyRecreation use not supported
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. Lake Memphremagog is listed impaired under Clean Water Act §303(d) (IR 4A) for hydrologic alteration, nutrients (phosphorus, nitrogen). Check local advisories before you swim.
Whether Lake Memphremagog 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 Lake Memphremagog
These are the measurements Vermont DEC publishes for Lake Memphremagog, 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 10.5 ft. Phosphorus 16.4 µg/L. Chlorophyll-a 5.5 µg/L. TSI 45.
| Measure | Reading | Where it sits |
|---|---|---|
| Water clarity (Secchi depth) | 10.5ft | Measured, not scored How deep a black-and-white disk stays visible from the surface. Higher is clearer. |
| Total phosphorus | 16.4µg/L | Fair GoodFairPoor |
| Chlorophyll-a (algae) | 5.5µg/L | Fair GoodFairPoor |
| Trophic state (TSI)Carlson's 0–100 index of how much algae a lake can support, from clarity, phosphorus and chlorophyll-a. | 45 | Mesotrophic OligotrophicMesotrophicEutrophicHypereutrophic |
Moderate nutrients, good water quality
Ask about Lake Memphremagog
Answers come straight from the public measurements and survey records on this page.
Lake Details
Max depth
~292 ft est.
Public access
Yes
Listed by Vermont DEC
Depth marked “est.” is a modeled maximum from GLOBathy (Khazaei et al. 2022, CC0), not a measured survey. Vermont has not published bathymetry for Lake Memphremagog.
Lake Size & Watershed
Watershed (drainage) area
677 sq mi
HydroLAKES / HydroSHEDS
Surface area
22,407 acres
HydroLAKES / HydroSHEDS
Shoreline
92.8 mi
HydroLAKES / HydroSHEDS
Elevation
673 ft
Size, shoreline, and watershed area from HydroLAKES (HydroSHEDS). Mean depth here is modelled, not surveyed — HydroLAKES v1.0 estimates lake depth from surrounding terrain rather than from soundings. Treat it as an approximation, and prefer a state bathymetric survey where one exists.
Recreation & Access
- Johns RiverPublic
- Whipple PointPublic
Named access points in the USGS National Boat Ramps inventory, within about 3 miles. More lakes with boat ramps
Stays via Stay22
Stays near Lake Memphremagog
Compare lakeside cabins, hotels, and vacation rentals near Lake Memphremagog in Orleans 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 Lake Memphremagog
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Fishing Lake Memphremagog
Water Quality Trend: Stable
Based on 6 years of monitoring (2020–2025).
Water clarity
Worsening6 years
Phosphorus
Stable-0.12 µg/L/yr6 years
Chlorophyll-a
Improving-0.43 µg/L/yr6 years
EPA Impairment Status
Lake Memphremagog is officially listed as impaired under Clean Water Act §303(d) in the 2022 EPA reporting cycle (IR category 4A).
Causes of impairment
Designated uses not supporting: Aquatic life, Recreation, Other.
A Total Maximum Daily Load (TMDL) plan has been approved.
Source: EPA ATTAINS assessment unit VT17-01L01_01 · Official waterbody report
Nearby Lakes in Orleans County
Frequently asked questions about Lake Memphremagog
Where is Lake Memphremagog?
- Lake Memphremagog is a lake in Orleans County, Vermont. Its water-quality measurements are published by Vermont DEC and shown on this page as reported.
What is the water quality of Lake Memphremagog?
- Lake Memphremagog in Orleans County, Vermont has water-quality measurements published by Vermont DEC, shown here as reported. Water clarity: 10.5 ft visibility. Phosphorus: 16.4 µg/L. Chlorophyll-a (algae): 5.5 µg/L.
Is Lake Memphremagog safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Lake Memphremagog is listed impaired under Clean Water Act §303(d) (IR 4A) for hydrologic alteration, nutrients (phosphorus, nitrogen). Check local advisories before you swim.
How deep is Lake Memphremagog?
- No published bathymetric survey covers Lake Memphremagog, so its depth has not been measured. The HydroLAKES global model estimates an average depth of about 292 feet, but that is a modelled estimate derived from surrounding terrain rather than a measurement on the water, so treat it as approximate.
Are there boat ramps on Lake Memphremagog?
- Lake Memphremagog has 2 documented boat landings in the USGS National Boat Ramps inventory. Named access points include Johns River, Whipple Point. Public access is listed as yes.
Can I fish at Lake Memphremagog?
- Lake Memphremagog 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 Vermont's fish and wildlife agency, so check its current regulations before you go.
Explore Lake Memphremagog across LakeQuality
Depth, room, public access, and the state wake-sport rules
Species activity outlook by water temperature and season
Where to stay at Vermont's top lakes, each with its readings
Vermont's cleanest lakes, ranked on agency measurements
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Where this data comes from
503 measurements from 4 monitoring stations, 2020–2025. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- Vermont Dept of Environmental Conservation
1VTDECWQ503 samples · 2020–2025
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
- 2130 B ~ Nephelometric Method
Monitoring station identifiers (4)
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
Lake size & watershed from HydroLAKES (HydroSHEDS)
Named boat-access points from the USGS National Boat Ramps inventory