Alder Lake is a lake in Ulster County, New York. Its water-quality measurements are published by NY DEC and shown on this page as reported.

How deep is Alder Lake?

Alder Lake has a maximum depth of 22 feet and an average depth of 8.9 feet. The lake covers 45 acres.

Alder Lake

Ulster County, New York45 acresView map Directions

No nutrient or algae sampling on record from NY DEC for this lake.

Max depth

22 ft

Bathymetric survey

Area

45 acres

Surface area

Shoreline

1.4 mi

Measured length

22 ft max depth

See the measurements Directions Where to stay

Alder Lake in Ulster County, New York has water-quality measurements published by NY DEC, shown here as reported. Maximum depth: 22 ft. Surface area: 45 acres.

Loading map…

Alder Lake is a 45-acre lake in Ulster County, New York with a maximum depth of 22 feet (9-foot average).

Source: EPA Water Quality Portal sampling records, NYSDEC. Methodology: how these readings are compared.

Swimming conditions

No reading

Not rated

Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.

Whether Alder Lake is safe to swim in today is a call for the New York Department of Environmental Conservation and the county health department, who post current advisories. LakeQuality does not issue swimming clearances.

Compare swimming lakes near Albany →

Get alerts for Alder Lake →

Water quality measurements for Alder Lake

These are the measurements NY DEC publishes for Alder 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. TSI undefined.

Ask about Alder Lake

Answers come straight from the public measurements and survey records on this page.

Lake Details

Max depth

22 ft

Average depth

8.9 ft

Surface area

45 acres

Shoreline

1.4 mi

Stays via Stay22

Stays near Alder Lake

Compare lakeside cabins, hotels, and vacation rentals near Alder Lake in Ulster 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 Alder Lake

Prices for Oct 16–18, 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 →

Follow Alder Lake’s readings

Email me when new measurements post for this lake. Updates stay free.

Or email

Fishing Alder Lake

→ Alder Lake fishing regulations (limits, seasons, special rules)

Nearby Lakes in Ulster County

Rondout Reservoir—View →Ulster Heights Lake—View →Cape Pond—View →Lyon Lake—View →Honk Lake—View →Ashokan Reservoir—View →

Frequently asked questions about Alder Lake

Where is Alder Lake?: Alder Lake is a lake in Ulster County, New York. Its water-quality measurements are published by NY DEC and shown on this page as reported.
What is the water quality of Alder Lake?: Alder Lake in Ulster County, New York has water-quality measurements published by NY DEC, shown here as reported. Maximum depth: 22 ft. Surface area: 45 acres.
Is Alder Lake safe to swim in?: Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.
How deep is Alder Lake?: Alder Lake has a maximum depth of 22 feet and an average depth of 8.9 feet. The lake covers 45 acres.