Reporting confirmed, active cyanobacteria blooms (HABs) by location within their respective watershed areas in New York State.

The information in this report is intended to help recreational water users enjoy summer at the lakes while avoiding any ill effects from confirmed blooms.

Exposure to hazardous algae blooms, (cyanobacteria) and the toxins they produce can pose health risks to people and pets.  Hazardous algae blooms/cyanobacteria can produce and release toxins in the water, even after the visible bloom has dissipated.

The good news is, the presence of a confirmed bloom in large lakes and rivers is in many cases contained to specific shorelines, coves or bays. The waterbodies included in this report may have clean and clear beaches and open water fully supporting recreational uses.  Check on your destination site conditions before heading out, and choose your access point in an area clear of HABs.

This report does not include marine algal blooms, impacting coastal beaches (red tide and brown tides), or filamentous green algae, which does not produce toxins.

Table of Contents

NY HABs Report for Nov 7 - 13, 2022. 1

Central Watersheds (12 active) 3

Upper Hudson River Watershed (0 active) 3

Mohawk River Watershed (0 active) 3

Lower Hudson River Watershed (9 active) 3

Kirk Lake (1 active) 3

Croton Falls Reservoir (1 active) 3

Ashokan Reservoir (1 active) 4

Alcove Reservoir (2 active) 4

Beaver Dam Lake (4 active) 4

Delaware River (1 active) 4

Loch Sheldrake (1 active) 4

Housatonic River (0 active) 4

Atlantic Ocean/Long Island Sound Watershed (2 active) 5

Prospect Park Lake (1 active) 5

Agawam Lake (1 active) 5

NE Watersheds (6 active) 5

Lake Champlain Watershed (4 active) 5

Mirror Lake (3 active) 5

Lake Colby (1 active) 6

St. Lawrence River Watershed (2 active) 6

Hyde Lake (2 active) 6

NW Watersheds (3 active) 6

Lake Ontario Minor Tributaries Watershed (0 active) 6

Black River Watershed (0 active) 6

Niagara River – Lake Erie Watershed (0 active) 6

Genesee River Watershed (0 active) 6

Oswego River – Finger Lakes Watershed (3 active) 7

Owasco Lake (2 active) 7

Otisco Lake (1 active) 7

South/West Watersheds (1 active) 7

Allegheny River Watershed (0 active) 7

Chemung River (1 active) 7

Lamoka Lake Channel (1 active) 7

Susquehanna River Watershed (0 active) 7

Ramapo River Watershed (0 active) 8

Central Watersheds (12 active) draining a portion of interior NYS down to the Atlantic Ocean via Long Island Sound, including the water supply for New York City

Upper Hudson River Watershed (0 active) drains an area in central NYS to the east of center, starting in the Adirondacks, flowing south toward Long Island Sound; the section south of Albany is reported as Lower Hudson River Watershed.

Mohawk River Watershed (0 active) drains the area starting just west of the center of NYS, and gathers run-off through the south side of the Adirondacks as it flows mainly east to join the Hudson River in Albany County. Schoharie Creek flows north from the Catskills and drains a channel of central state north to join the Mohawk River.

Lower Hudson River Watershed (9 active) draining the lower portion of New York State interior out to the Atlantic.

Kirk Lake (1 active)

• Nov 4, 11:30 pm large localized bloom confirmed in Putnam County remains active this week.

Croton Falls Reservoir (1 active)

• Nov 2, 12 pm widespread/lakewide bloom confirmed in Putnam County remains active this week.

Ashokan Reservoir (1 active)

• Nov 1, 3:39 pm large localized bloom confirmed in Ulster County. Reported by the NYC DEP. 

Alcove Reservoir (2 active)

• Nov 3, 10:30 am widespread/lakewide bloom confirmed in Albany County remains active this week.
• Nov 1, 1:30 pm large localized bloom confirmed in Albany County remains active this week.

Beaver Dam Lake (4 active)

• Nov 3, 9:23 am large localized bloom confirmed off the north shore of the main body of water, east of the north arm in Orange County remains active this week.
• Oct 30, 11 am large localized bloom confirmed off the north shore in the bay on the east side of the water body in Orange County remains active this week; the nearest land point of reference is the intersection of Shore Dr and Chestnut Ave.
• Oct 30, 10:53 am large localized bloom confirmed off the north shore toward the east side of the water body off the north shore, at the mouth of the east bay in Orange County. Reported by the public.
• Oct 30, 10:28 am large localized bloom confirmed in Orange County. Reported by the public.

Delaware River (1 active) draining Sullivan and Delaware Counties to the Atlantic via Long Island Sound.

Loch Sheldrake (1 active)

• Oct 31, 4:20 pm widespread/lakewide bloom confirmed in the south end of the water body, the bay furthest east in Sullivan County, remains active this week.

Housatonic River (0 active) draining a small part of Dutchess County, the river itself originates in Vermont, flows south through Massachusetts and Connecticut to the outlet into Long Island Sound east of Bridgeport.

Atlantic Ocean/Long Island Sound Watershed (2 active)

Drains the city brooks, creeks and rivers into Long Island Sound.

Prospect Park Lake (1 active)

• Oct 28, 10:37 am widespread/lakewide bloom confirmed in Kings County (Brooklyn) remains active this week.

Agawam Lake (1 active)

• Nov 2, 10:36 am widespread/lakewide bloom of confirmed in Suffolk County remains active this week.

NE Watersheds (6 active) draining upstate NY out to the St. Lawrence River. Flows originate in the north-central Adirondacks, flowing generally north and east to the St. Lawrence River and out to the Atlantic Ocean.

Lake Champlain Watershed (4 active)

Mirror Lake (3 active)

• Nov 4, 4:30 pm large localized bloom confirmed mid-lake toward the south end of the water body in Essex County. Reported by the public.
• Nov 2, 4:15 pm small localized bloom confirmed off the west shore halfway down the west shoreline in Essex County remains active this week.
• Oct 31, 3:30 pm widespread/lakewide bloom confirmed off the west shore toward the north end of the water body in Essex County remains active this week. 

Lake Colby (1 active)

• Oct 30, 2:02 pm large localized bloom confirmed in Franklin County remains active this week.

St. Lawrence River Watershed (2 active)

Hyde Lake (2 active)

• Nov 4, 7:43 am widespread bloom confirmed in Jefferson County. Reported by the public.
• Nov 2, 3:39 pm large localized bloom confirmed in Jefferson County remains active this week.

NW Watersheds (3 active) (draining west to Lake Erie or Lake Ontario)

Lake Ontario Minor Tributaries Watershed (0 active)

Black River Watershed (0 active) draining an area of central NYS west to Lake Ontario

Niagara River – Lake Erie Watershed (0 active) draining northwest NYS west to Lake Erie

Genesee River Watershed (0 active) draining a band of west-central NYS from the south border to the north, emptying into Lake Ontario at Rochester, Monroe County

Oswego River – Finger Lakes Watershed (3 active)

Owasco Lake (2 active)

• Oct 28, 2:42 pm small localized bloom confirmed in Cayuga County remains active this week.

Otisco Lake (1 active)

• Oct 30, 3 pm large localized bloom confirmed in Onondaga County remains active this week.

South/West Watersheds (1 active) draining southwest NYS west to the Ohio River/Mississippi system, and the watersheds draining the south central NYS down to the Atlantic via Chesapeake Bay)

Allegheny River Watershed (0 active) – drains West to the Ohio River.

Chemung River (1 active) drains central NYS south to Susquehanna River and out to Chesapeake Bay/Atlantic Ocean.

Lamoka Lake Channel (1 active)

• Nov 3, 10:20 am large localized bloom confirmed in Schuyler County remains active this week.

Susquehanna River Watershed (0 active) drains south-central New York State flowing southwest, then south, eventually emptying into the Atlantic Ocean at Chesapeake Bay.

Ramapo River Watershed (0 active) drains a small section in the southeast part of New York State south through New Jersey and out into the Atlantic Ocean at Chesapeake Bay.