Harmful Algal Blooms

As our climate continues to warm and extreme weather events increase, Harmful Algal Blooms are becoming increasingly present across Western New York’s waterways during the warmer months. They are a problem we all need to be on the lookout for to keep our families and our pets safe. 

Buffalo Niagara Waterkeeper continues to test and report problems to the appropriate regulatory agencies, such as the Department of Environmental Conservation (DEC) and the Erie County Department of Health, while relying on the public to inform us of possible blooms spotted around the watershed. 

• Know It: Know how to identify potential HABs and the conditions that might trigger them
• Avoid It: People, pets, and livestock should avoid contact with any floating mats, scums, or discolored water. Do not drink, prepare food, cook, or make ice with untreated surface water.  
• Report It: If you see a suspected HAB, please report it to NYS DEC (HABsInfo@dec.ny.gov) and Buffalo Niagara Waterkeeper (rcoady@bnwaterkeeper.org). Be sure to take multiple high-quality, landscape oriented photos of the waterway to include in your reports. 

Contact Information

Robert Coady
716.852.7483, ext. 19
rcoady@bnwaterkeeper.org

A Harmful Algal Bloom (HAB) can occur when algae multiply rapidly, often forming visible patches on the surface of water. 

Note that algae is an important part of a healthy waterway. The sight of algae on or in water is not the issue, but under certain circumstances the algae will grow – or bloom – and problems can occur. These blooms may occur:

• During periods of prolonged warm temperatures and sunlight
• When excessive nutrients – like nitrogen or phosphorus – are in the water 
• There is little or no moving water.

These circumstances can lead to an explosion in algae growth that will lead to a Harmful Algal Bloom (HAB or HABs). The harm from a bloom is that it can limit oxygen for aquatic life, cause unsightly or odor problems, and in some cases produce toxins harmful to humans and animals.  

Depending on the weather and the characteristics of the waterway, HABs may be short-lived (appearing and disappearing in hours) or long-lived (persisting for several weeks or more) (Department of Environmental Conservation). 

Click the image above to see key factors that can create Harmful Algal Blooms

Contacting some types of harmful algal blooms can lead to irritation to the stomach, skin, eye, and throat, allergic reactions, or breathing difficulties. Pets, including dogs, that contact HABs through swimming or drinking affected water can experience similar symptoms. If you think you’re experiencing health risks associated with a HAB, consider visiting a healthcare professional. 

Report symptoms to your local health department. For more information visit: https://www.health.ny.gov/environmental/water/drinking/bluegreenalgae/.

Image by EPA. View full document here

Since it is hard to distinguish a HAB from non-harmful blooms, it’s important to avoid coming into any contact with the water if signs of a bloom are present. 

Signs that could indicate the presence of a HAB include floating mats of algae or scums, and discoloration in waterways. Colors can include shades of green, blue-green, yellow, brown, or red. Algal blooms can also appear in different textures, including parallel streaks, dots, clumps, or paint-like.

 Click here  for some visual clues to help you identify a potential bloom. 

Please keep an eye out for HABs while recreating in area waterways during the hot, dry months of the year. Note that toxins potentially produced by a HAB might still be present even after it is no longer visible.  

Ellicott creek, downstream of Ellicott Creek Park, has a Harmful Algal Bloom along it in this July 2024 photograph. Image by Ryan Sajdak 

All around the United States, runaway algae growth caused by water pollution is threatening ecosystems, as well as people’s health and livelihood. Harmful blooms are a worldwide issue and are expected to worsen with warming waters caused by climate change. In the United States, many Waterkeeper organizations and affiliates are working to stop the release of pollutants that cause these blooms.  

1) Reduce or eliminate the over-application of pesticides and fertilizers near waterbodies, especially if rain is forecasted within a few days of the application.  

2) Encourage landowners or operators adjacent to vulnerable waterbodies to not mow to the water’s edge, allow for a buffer zone of vegetation to help filter surface run-off into waterways.  

3) Advocate to our elected officials about your concern about HABs and the need for more monitoring, testing, and projects that can help alleviate this growing problem.   

4) Report the problem 

5) Make a donation to BNW to support programs like Riverwatch, which samples for HABs and other threats to our waterways and keeps the public informed.

Please report suspected blooms to the New York State Department of Environmental Conservation. The best way to report a suspected bloom is to fill out and submit a Suspicious Algal Bloom Report Form here. You will need photos of the bloom in landscape orientation showing how widespread the bloom is and a closeup of the bloom.  

You can also reach out to HABsInfo@dec.ny.gov with questions or issues with the report form. It is important to report any suspected bloom, as cyanobacteria are not the only algae that can result in blooms. The DEC has expanded its HABs monitoring program to include other species of algae in addition to cyanobacteria.

You can also fill out the Google form below for Buffalo Niagara Waterkeeper, which will allow you to upload images so staff can stay informed and visit the site, if possible.

An image of a Harmful Algal Bloom (HAB) in the water.

Affected areas are listed on the New York State Department of Environmental Conservation website map here. 

You can also subscribe to the DEC newsletter here.

Not all HABS are the result of cyanobacteria. Most notably, waterways such as Ellicott Creek and Tonawanda Creek have experienced blooms of Euglena, a single-celled flagellated protist.

The only way to tell the difference between a Euglena Bloom and a Cyanobacteria Bloom is with a microscope. To better understand the extent of potential HABs in our waterways, and to properly elevate concerns, we ask that any algae bloom, regardless of appearance, be reported to the DEC and to BNW staff.  

Please note that for the map below, narrative results in the call out box of a sample are categorized by USGS Hydrologic Unit Codes (HUC), which may appear as different waterways from where the actual sample was taken. The location pin on the map indicates the actual waterbody