Caspian Lake
Orleans County, Vermont789 acresView mapDirections
Vermont DEC publishes the water-quality measurements for Caspian Lake. Here is what has been measured.
- Oligotrophic
- 57 ft max depth
Caspian Lake in Orleans County, Vermont has water-quality measurements published by Vermont DEC, shown here as reported. Water clarity: 29.5 ft visibility. Phosphorus: 7.8 µg/L. Chlorophyll-a (algae): 1.3 µg/L. Surface area: 789 acres.
Caspian Lake is a 789-acre cold, clear oligotrophic lake in Orleans County, Vermont with an estimated average depth of about 57 feet. Overall water quality is improving over recent sampling years. Compared to the 16 other monitored lakes in Orleans County, Caspian Lake ranks #1 for water quality.
Source: EPA Water Quality Portal sampling records, VT DEC, last sampled 2025-08-11. Methodology: how these readings are compared.
Caspian Lake covers about 790 acres in Orleans County. Vrbo is where to look for cabins and lake homes around Caspian Lake, and Booking.com and Expedia search hotels near the lake for your dates.
What Caspian Lake is good for
From access and monitoring records, not editorial picks.
- Clear water29.5 ft of visibility
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 Caspian 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 Caspian Lake
These are the measurements Vermont DEC publishes for Caspian Lake, shown as reported. The condition class beside each reading is the EPA National Lakes Assessment class for this lake’s ecoregion.
Crystal clear, you can see 29.5 ft down. Phosphorus 7.8 µg/L. Chlorophyll-a 1.3 µg/L. TSI 32.
| Measure | Reading | Where it sits |
|---|---|---|
| Water clarity (Secchi depth) | 29.5ft | Measured, not scored How deep a black-and-white disk stays visible from the surface. Higher is clearer. |
| Total phosphorus | 7.8µg/L | Good GoodFairPoor |
| Chlorophyll-a (algae) | 1.3µg/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. | 32 | Oligotrophic OligotrophicMesotrophicEutrophicHypereutrophic |
Low nutrients, clear water. No reading is a swimming clearance.
Ask about Caspian Lake
Answers come straight from the public measurements and survey records on this page.
Lake Details
Max depth
~57 ft est.
Surface area
789 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 Caspian Lake.
Lake Size & Watershed
Watershed (drainage) area
7 sq mi
HydroLAKES / HydroSHEDS
Shoreline
5.4 mi
HydroLAKES / HydroSHEDS
Elevation
1,398 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.
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Stays near Caspian Lake
Compare lakeside cabins, hotels, and vacation rentals near Caspian Lake 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 Caspian Lake
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Fishing Caspian Lake
Water Quality Trend: Improving
Based on 6 years of monitoring (2020–2025).
Water clarity
Stable6 years
Phosphorus
Improving-0.79 µg/L/yr6 years
Chlorophyll-a
Improving-0.41 µg/L/yr6 years
Reservoir Info (USACE NID)
Caspian Lake is a man-made reservoir impounded by the Caspian Lake (completed 1929), built primarily for hydroelectric on the Greensboro Brook; earth-type dam, 7 ft tall and 205 ft long.
- Surface area
- 789 ac
- Normal storage
- 0 ac-ft
- Max storage
- 4,300 ac-ft
- Drainage area
- 7.05 sq mi
- Hazard class
- Significant
- Owner
- HARDWICK ELECTRIC DEPARTMENT
All listed purposes: Hydroelectric;Recreation.
Source: USACE National Inventory of Dams, NID ID VT00183 · Operator website
Nearby Lakes in Orleans County
Frequently asked questions about Caspian Lake
Where is Caspian Lake?
- Caspian Lake 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 Caspian Lake?
- Caspian Lake in Orleans County, Vermont has water-quality measurements published by Vermont DEC, shown here as reported. Water clarity: 29.5 ft visibility. Phosphorus: 7.8 µg/L. Chlorophyll-a (algae): 1.3 µg/L. Surface area: 789 acres.
Is Caspian Lake safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.
How deep is Caspian Lake?
- No published bathymetric survey covers Caspian Lake, so its depth has not been measured. The HydroLAKES global model estimates an average depth of about 57 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 789 acres.
Explore Caspian Lake across LakeQuality
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Where this data comes from
298 measurements from 2 monitoring stations, 2020–2025. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- Vermont Dept of Environmental Conservation
1VTDECWQ298 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 (2)
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)