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Blue-Green Algal Bloom Notices

Sign up for MakingWaves to receive weekly email updates about blue-green algae bloom notifications. To subscribe to MakingWaves, first subscribe to GovDelivery, and check the box next to MakingWaves on the list of topics.


The map below displays the current blue-green algae bloom notices. Each location is labeled with a number that corresponds to the information in the table below.

There may be other waterbodies with blue-green algae blooms that have not been reported to the DEC.

The table provides more information about the location and status of the notice. The information presented was collected during routine DEC lake monitoring programs, by Citizen Statewide Lake Assessment Program volunteers, and from public reports.

Blooms of other algae are not reported here. The 'What Should You Do' advice provided below should also be followed when blooms not reported here are encountered.

Regulated swimming beaches are regularly monitored and evaluated for the presence of blue-green algae blooms. For information about regulated swimming beaches contact your local health department.

Map and table information is updated weekly

This page was updated on 10/17/2014. Call the DEC regional office for the most current information or to report a blue-green algae bloom.

DEC encourages the public to view the archive reports table to be aware of lakes that have been removed from the notification map.

Map of waterbodies with a blue-green algae bloom notice in NY.

*Monitoring programs are the Lake Classification and Inventory Survey (LCI) and Citizens Statewide Lake Assessment Program (CSLAP). For specific information about the current sampling results for the lakes sampled through the 2014 NYSDEC Lake Monitoring Program (PDF, 72 KB), contact Division of Water at 518-402-8179.

Lake Champlain blooms are not reported here. For information about blue-green algae on Lake Champlain, visit the Lake Champlain Committee monitoring page and the Vermont Department of Health's blue-green algae notification page (above two links leave DEC website.)

Waterbodies with Blue-Green Algae Notices
Map Number Waterbody Name County Status Extent of bloom Status Date Type of Sample Change in Status
1 Allegheny Reservoir* Cattaraugus Confirmed Large localized 10/6/2014 Lab sample Updated listing
2 Arctic Lake Broome Suspicious Large localized 10/17/2014 Visual Updated listing
3 Barnum Pond Franklin Suspicious Large localized 9/28/2014 Visual No change
4 Beaver Dam Lake Orange Confirmed Small localized 10/12/2014 Lab sample Updated listing
5 Beaver Lake Broome Suspicious Large localized 10/16/2014 Visual Updated listing
6 Black Lake* St. Lawrence Suspicious Widespread 9/25/2014 Visual No change
7 Boyd Lake Jefferson Suspicious Widespread 10/16/2014 Visual Updated listing
8 Butterfield Lake Jefferson Confirmed Large localized 10/12/2014 Lab sample New listing
9 Cazenovia Lake Madison Confirmed Large localized 9/29/2014 Lab sample No change
10 Central Park Lake New York Suspicious Widespread 10/10/2014 Visual Updated listing
11 Chautauqua Lake* Chautauqua CONFIRMED WITH HIGH TOXINS Large localized 9/27/2014 Lab sample No change
12 Copake Lake Columbia Suspicious Not reported 10/16/2014 Visual Updated listing
13 Cossayuna Lake Washington Suspicious Small localized 9/30/2014 Visual No change
14 Deans Pond Cortland Confirmed Large localized 9/28/2014 Lab sample No change
15 Duane Lake Schenectady Suspicious Widespread 10/13/2014 Visual Updated listing
16 Georgica Pond Suffolk Confirmed Small localized 10/14/2014 Lab sample Updated listing
17 Grass Lake St. Lawrence Confirmed Not reported 9/25/2014 Lab sample No change
18 Harlem Meer New York Suspicious Widespread 10/10/2014 Lab sample Updated listing
19 Katonah Lake Westchester Confirmed Open water 9/26/2014 Lab sample No change
20 Kirk Lake Putnam Confirmed Not reported 10/3/2014 Lab sample No change
21 Lake Agawam Suffolk Confirmed Widespread 10/14/2014 Lab sample Updated listing
22 Lake Huntington Sullivan Confirmed Large localized 10/3/2014 Lab sample No change
23 Lake Lacoma Monroe Suspicious Large localized 9/28/2014 Visual No change
24 Lake Mohegan Westchester Confirmed Widespread 10/14/2014 Lab sample Updated listing
25 Lake Neatahwanta Oswego Confirmed Not reported 10/8/2014 Lab sample No change
26 Lawsons Lake Albany CONFIRMED WITH HIGH TOXINS Large localized 10/2/2014 Lab sample Updated listing
27 Mill Pond Suffolk Confirmed Widespread 10/14/2014 Lab sample Updated listing
28 Owasco Lake* Cayuga Suspicious Large localized 10/12/2014 Lab sample Updated listing
29 Petonia Lake Chenango Confirmed Small localized 9/26/2014 Lab sample No change
30 Rockland Lake Rockland Suspicious Small localized 10/10/2014 Visual No change
31 Smith Pond Steuben Confirmed Not reported 10/13/2014 Lab sample New listing
32 Song Lake Cortland Confirmed Large localized 10/10/2014 Lab sample Updated listing
33 We Wah Lake Orange Suspicious Small localized 10/6/2014 Visual No change

* blooms in large lakes may be limited to shorelines or confined bays. Portions of any of these lakes may be clear and fully support recreational uses

Status & Extent of Bloom Categories

Suspicious-what does this mean?

Conditions at these waterbodies fit the description of a blue green algae bloom, based on visual observations and/or digital photographs.

It is not known if there are harmful toxins in the water

Blooms may be present in all or part of the waterbody. Laboratory analysis has not been done to determine if this is a blue-green algae bloom. Blue green algae are irritants to some people even if toxins are not present.

Confirmed-what does this mean?

Water sampling results have confirmed the presence of a blue green algae bloom which may produce toxins.

Waterbodies noted with "HIGH TOXINS" indicate that laboratory data suggests that there are toxins in enough quantities to cause health effects when people and animals come in contact with the water through swimming or drinking.

Waterbodies noted as "open water" indicate that the bloom is widespread and bloom conditions may be worse along shorelines and within recreational areas. Special precautions should be taken in situations when "HIGH TOXINS" are also reported with "open water" because toxins are likely to be higher in shoreline areas.

Blooms and toxins may be present in all or part of the waterbody.

Extent of Bloom-what does this mean?

The extent of the bloom is an estimate of the size of the bloom within the waterbody and is recorded by monitoring program staff or from public reports.

Small Localized: Blooms affecting a small area of the Lake, limited from one to several neighboring properties.

Large Localized: Blooms affecting many properties within an entire cove, along a large segment of the shoreline, or in a specific region of the lake.

Widespread: Blooms affecting the entire lake, a large portion of the lake, or most to all of the shoreline.

Open water: Sample was collected near the center of the lake and may indicate that the bloom is widespread. Algae or toxin levels in some shoreline areas could be highly elevated.

What should I do?

  • If you believe you have been exposed to a bloom and are experiencing symptoms, seek immediate medical attention and contact the local health department.
  • If people or pets are exposed to a bloom, rinse with clean water.
  • People and pets should stay out of any water that is discolored, has surface scums or shows other evidence of a bloom.
  • Don't drink the water in or near the bloom- boiling water does not protect people or pets from blue-green algal toxins.
  • Anglers should not eat fish caught from areas that look like spilled paint or pea soup.
  • For more information about health concerns visit http://www.health.ny.gov/ and search "blue green algae".
  • More information about blue-green algae blooms.

Suspect a blue-green algae bloom?

If you suspect that you have seen a blue-green algae bloom or you, your family, or pet has been in contact with a blue-green algae bloom follow the 'What should I do?' advice and please fill out and submit the Suspicious Algae Bloom Report Form (PDF, 527 KB).

You are encouraged to include digital photographs as email attachments with the form (close-up, and landscape showing extent and location of bloom). If possible, please include an image from an online mapping application such as Google, Bing or Yahoo Maps, with a marker at the bloom location.

You may also contact your regional DEC office or contact:

Scott Kishbaugh, Division of Water
Phone: (518) 402-8179
Email the Division of Water

Want to receive weekly updates?

Sign up to the Division of Water's Making Waves email listserve to receive weekly updates on blue-green algae bloom notices in New York waterbodies. Making Waves also provides information about new and important water-related issues, events and news, which could affect your watershed.

To subscribe to the MakingWaves listserve Subscribe to GovDelivery ,and enter the requested information. When you reach the topics page, check the "Making Waves" box under the "Water" category. You can expect to receive an email from this listserve about once a week. We encourage you to subscribe and to share the listserve with others.