Sleepy Hollow Lake
Greene County, New York324 acresView mapDirections
Not Rated: one monitoring station are on record, but they measured water clarity only. LakeQuality’s A–F method grades total phosphorus, total nitrogen, chlorophyll-a, and turbidity; clarity is shown, not scored.
- Impaired · Nutrients (phosphorus, nitrogen)
- 57 ft max depth
- Limited data
Sleepy Hollow Lake in Greene County, New York is not rated for water quality — its monitoring record does not meet the evidence bar. Water clarity: 5.9 ft visibility. Surface area: 324 acres.
- Clarity
- 5.9 ft
- Max depth
- ~57 ft est.
- Area
- 324 acres
Stays via Stay22
Stays near Sleepy Hollow Lake
Compare lakeside cabins, hotels, and vacation rentals near Sleepy Hollow Lake in Greene 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 Sleepy Hollow Lake
Prices for Sep 11–13, 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 whole trip? See where to stay at New York’s top lakes →
Watch Sleepy Hollow Lake’s letter
Email me if this lake’s grade moves. Grades stay free.
Or email
Why Sleepy Hollow Lake has no grade
Sleepy Hollow Lake has monitoring on record from one station, but only water clarity was measured. LakeQuality’s A–F letter uses total phosphorus, total nitrogen, chlorophyll-a, and turbidity against EPA National Lakes Assessment condition classes. With none of those grading measurements on record, Sleepy Hollow Lake is Not Rated — not an F. Its 5.9-foot median from 8 readings collected 2020 is still shown as clarity, but clarity alone cannot earn a letter.
Not Rated is EPA Integrated Reporting Category 3 — insufficient information. Everything below that has been measured is still reported on this page.
Sampling is run by NYSDEC and volunteer programs, and published through the EPA Water Quality Portal. Read the full grading methodology.
Sleepy Hollow Lake is a 324-acre lake in Greene County, New York with an estimated average depth of about 57 feet.
Source: EPA Water Quality Portal sampling records, NYSDEC, last sampled 2020-09-22. Grade methodology: LakeQuality methodology.
Swimming Safety
Not ratedLimited data
The letter is not a swimming clearance. Sleepy Hollow Lake is listed impaired under Clean Water Act §303(d) (IR 5) for nutrients (phosphorus, nitrogen). Check local advisories before you swim.
Water quality measurements for Sleepy Hollow Lake
These readings exist but are not enough for an A–F grade — see why.
Murky, only visible to about 5.9 ft. TSI 52.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 5.9 ft | Not graded |
| Phosphorus | No recent samples | |
| Chlorophyll-a (Algae) | No recent samples | |
| Trophic State Index (TSI) | 52 | Eutrophic |
High nutrients, frequent algae, reduced clarity
Lake Details
| Characteristic | Value |
|---|---|
| Maximum Depth | ~57 ft est. |
| Average Depth | ~55 ft est. |
| Surface Area | 324 acres |
Depth marked “est.” is a modeled maximum from GLOBathy (Khazaei et al. 2022, CC0), not a measured survey. New York has not published bathymetry for Sleepy Hollow Lake.
Lake Size & Watershed
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.
Fishing Sleepy Hollow Lake
Reservoir Info (USACE NID)
Sleepy Hollow Lake is a man-made reservoir impounded by the Sleepy Hollow Dam (completed 1972), built primarily for recreation on the MURDERERS CREEK; earth-type dam, 83 ft tall and 753 ft long.
- Surface area
- 324 ac
- Normal storage
- 8,400 ac-ft
- Max storage
- 13,500 ac-ft
- Drainage area
- 13.3 sq mi
- Hazard class
- High
- Owner
- ASSOC OF PROPERTY OWNERS OF SLEEPY HOLLOW LAKE, INC.
All listed purposes: Recreation;Water Supply.
Source: USACE National Inventory of Dams, NID ID NY00142 · Operator website
EPA Impairment Status
Sleepy Hollow Lake is officially listed as impaired under Clean Water Act §303(d) in the 2022 EPA reporting cycle (IR category 5).
Causes of impairment
Source: EPA ATTAINS assessment unit NY1301-0059 · Official waterbody report
Regulated Pollution Sources Nearby
22 EPA-permitted facilities operate within about 5 miles of Sleepy Hollow Lake under Clean Water Act (NPDES) discharge permits, including 4 classified by the EPA as major dischargers. 11 facilities have a reported Clean Water Act violation in the past three years.
- Hudson (C) StpHudson · 2.5 mi away · NPDES NY0022039MajorRecent violation
- Town Of Greenport StpHudson · 3.4 mi away · NPDES NY0030988MajorRecent violation
- Coxsackie (V) StpCoxsackie · 3.9 mi away · NPDES NY0033545MajorRecent violation
- New Athens Generating Co, LlcAthens · 4 mi away · NPDES NY0261009MajorRecent violation
- Sleepy Hollow Lake StpAthens · 1.1 mi away · NPDES NY0025291Recent violation
- Brick Row StpAthens · 1.3 mi away · NPDES NY0020877Recent violation
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.
Graded lakes near Sleepy Hollow Lake
Sleepy Hollow Lake has no grade, but these lakes within a short drive do.
Nearby Lakes in Greene County
Frequently asked questions about Sleepy Hollow Lake
Where is Sleepy Hollow Lake?
- Sleepy Hollow Lake is a lake in Greene County, New York. LakeQuality has not rated this lake (UNRATED) — the only measurement available is water clarity, which is not a water-quality indicator on its own — EPA's National Lakes Assessment does not grade clarity.
What is the water quality grade for Sleepy Hollow Lake?
- Sleepy Hollow Lake in Greene County, New York is not rated for water quality — its monitoring record does not meet the evidence bar. Water clarity: 5.9 ft visibility. Surface area: 324 acres.
Is Sleepy Hollow Lake safe to swim in?
- The letter is not a swimming clearance. Sleepy Hollow Lake is listed impaired under Clean Water Act §303(d) (IR 5) for nutrients (phosphorus, nitrogen). Check local advisories before you swim.
How deep is Sleepy Hollow Lake?
- No published bathymetric survey covers Sleepy Hollow 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 324 acres.
Explore Sleepy Hollow Lake across LakeQuality
Depth, room, public access, and the state wake-sport rules
4 documented falls within 24.6 mi, nearest High Falls (Philmont)
Species activity outlook by water temperature and season
Where to stay at New York's top lakes, each with its grade
New York's cleanest and most-polluted lakes, ranked
More New York Lake Rankings
Other Lakes in New York
Eutrophic Lakes in New York
Where this data comes from
8 measurements from 1 monitoring station, 2020. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- North American Lake Management Society
NALMS8 samples · 2020
Monitoring station identifiers (1)
Grade thresholds from the EPA National Lakes Assessment (EPA 841-R-24-006, Table 6-3), applied by ecoregion. See how grades are calculated and data sources.
Other records on this page
Impairment status from EPA ATTAINS 303(d) database
Regulated discharger data from EPA ECHO (ICIS-NPDES)
Lake size & watershed from HydroLAKES (HydroSHEDS)