Online Notification System for Harmful Algal Blooms

New Yorkers are reminded to be aware of harmful algal blooms as the 2025 HABs notification season starts.

The Department of Environmental Conservation’s New York Harmful Algal Bloom System is now active, providing residents the ability to send reports of HABs electronically via a user- and mobile phone-friendly form.

DEC and the Department of Health evaluate HAB reports, and once confirmed, reports are posted to https://dec.ny.gov/environmental-protection/water/water-quality/harmful-algal-blooms/notifications.

While cyanobacteria are naturally occurring in the environment, certain conditions lead to accumulations that become HABs. Blooms are likely triggered by a combination of factors that include excess nutrients such as phosphorus and nitrogen, lots of sunlight, low-water or low-flow conditions, calm water, and warm temperatures.

HAB occurrence and reporting typically increase throughout the season, with the most reports received during the warmest months of August and September.

Regardless of the presence of toxins, HABs can pose a risk to public health.

“As we enter the summer months and people find themselves enjoying New York State’s waters, we encourage them to avoid and report any harmful algal blooms as they can cause health effects in both people and pets,” said Health Commissioner Dr. James McDonald. “The department will continue our work with local water suppliers, beach operators, and the Department of Environmental Conservation to monitor for harmful algal blooms so that we may protect drinking water and recreational use of our freshwaters.”

When it comes to HABs, DEC encourages New Yorkers to “know it, avoid it, report it.”

HABs vary in appearance from scattered green dots in the water to long, linear green streaks, pea soup or spilled green paint, to blue-green or white coloration.

People, pets, and livestock should avoid contact with water that is discolored or has algal scums on the surface.

If members of the public suspect a HAB, they should report it online. Symptoms or health concerns related to HABs should be reported to the health department via email to harmfulalgae@health.ny.gov.

Using the most up-to-date research on controllable causes, DEC established a holistic approach to managing and reducing HABs in the state that combines long- and short-term strategies along with advancing research. DEC’s approach includes deliberate clean water planning to improve nutrient reduction efforts, funding to implement nutrient reduction, applied research, and short-term mitigation efforts.

To date, New York State awarded more than $530 million in grants designed to reduce the frequency of algal blooms across the state by targeting phosphorus and nitrogen pollution – controllable factors that can contribute to the occurrence of HABs, and more than $14.4 million to research and development, pilot projects, and advanced HABs monitoring.