Lake Mansfield
Lamoille County, Vermont38 acresView mapDirections
Vermont DEC publishes the water-quality measurements for Lake Mansfield. Here is what has been measured.
- Mesotrophic
- 19 ft max depth
Lake Mansfield in Lamoille County, Vermont has water-quality measurements published by Vermont DEC, shown here as reported. Water clarity: 6.9 ft visibility. Phosphorus: 12.1 µg/L. Chlorophyll-a (algae): 3.1 µg/L. Surface area: 38 acres.
Lake Mansfield is a 38-acre mesotrophic lake in Lamoille County, Vermont with an estimated average depth of about 19 feet. Overall water quality is declining over recent sampling years. Compared to the 5 other monitored lakes in Lamoille County, Lake Mansfield ranks #4 for water quality.
Source: EPA Water Quality Portal sampling records, VT DEC, last sampled 2024-06-12. Methodology: how these readings are compared.
Lake Mansfield covers about 38 acres in Lamoille County. Vrbo is where to look for cabins and lake homes around Lake Mansfield, and Booking.com and Expedia search hotels near the lake for your dates.
Swimming conditions
Readings onlyLow 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. Check local advisories before you swim.
Whether Lake Mansfield 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 Mansfield
These are the measurements Vermont DEC publishes for Lake Mansfield, shown as reported. The condition class beside each reading is the EPA National Lakes Assessment class for this lake’s ecoregion.
Moderate clarity, visible to about 6.9 ft. Phosphorus 12.1 µg/L. Chlorophyll-a 3.1 µg/L. TSI 44.
| Measure | Reading | Where it sits |
|---|---|---|
| Water clarity (Secchi depth) | 6.9ft | Measured, not scored How deep a black-and-white disk stays visible from the surface. Higher is clearer. |
| Total phosphorus | 12.1µg/L | Good GoodFairPoor |
| Chlorophyll-a (algae) | 3.1µg/L | Good GoodFairPoor |
| Trophic state (TSI)Carlson's 0–100 index of how much algae a lake can support, from clarity, phosphorus and chlorophyll-a. | 44 | Mesotrophic OligotrophicMesotrophicEutrophicHypereutrophic |
Moderate nutrients, good water quality
Ask about Lake Mansfield
Answers come straight from the public measurements and survey records on this page.
Lake Details
Max depth
~19 ft est.
Surface area
38 acres
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 Mansfield.
Lake Size & Watershed
Watershed (drainage) area
4 sq mi
HydroLAKES / HydroSHEDS
Shoreline
1.2 mi
HydroLAKES / HydroSHEDS
Elevation
1,165 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.
Stays via Stay22
Stays near Lake Mansfield
Compare lakeside cabins, hotels, and vacation rentals near Lake Mansfield in Lamoille 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 Mansfield
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Fishing Lake Mansfield
Water quality readings over time
2 seasons of samples on record (2023–2024). Calling a direction takes at least 4 years of the same measurement.
Phosphorus
Worsening+4.9 µg/L/yr2 years
Chlorophyll-a
Worsening+1.6 µg/L/yr2 years
Reservoir Info (USACE NID)
Lake Mansfield is a man-made reservoir impounded by the Lake Mansfield (completed 1900), built primarily for recreation on the Miller Brook; earth-type dam, 32 ft tall and 375 ft long.
- Surface area
- 38 ac
- Normal storage
- 0 ac-ft
- Max storage
- 515 ac-ft
- Drainage area
- 2.48 sq mi
- Hazard class
- High
- Owner
- LAKE MANSFIELD TROUT CLUB
Source: USACE National Inventory of Dams, NID ID VT00100 · Operator website
Nearby Lakes in Lamoille County
Frequently asked questions about Lake Mansfield
Where is Lake Mansfield?
- Lake Mansfield is a lake in Lamoille 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 Mansfield?
- Lake Mansfield in Lamoille County, Vermont has water-quality measurements published by Vermont DEC, shown here as reported. Water clarity: 6.9 ft visibility. Phosphorus: 12.1 µg/L. Chlorophyll-a (algae): 3.1 µg/L. Surface area: 38 acres.
Is Lake Mansfield safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.
How deep is Lake Mansfield?
- No published bathymetric survey covers Lake Mansfield, so its depth has not been measured. The HydroLAKES global model estimates an average depth of about 19 feet, but that is a modelled estimate derived from surrounding terrain rather than a measurement on the water, so treat it as approximate. The lake covers 38 acres.
Explore Lake Mansfield across LakeQuality
2 documented falls within 9.2 mi, nearest Bingham Falls
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Where this data comes from
25 measurements from 1 monitoring station, 2021–2024. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- Vermont Dept of Environmental Conservation
1VTDECWQ25 samples · 2021–2024
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
- 2130 B ~ Nephelometric Method
- 2120 B ~ Color in Water by Visual Comparison
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
Lake size & watershed from HydroLAKES (HydroSHEDS)