Everything You Need To Know About Harmful Algal Bloom Management

By Peter Chawaga

As summer ends, water systems around the country are finding relief from the peak season for one of their most vexing obstacles.

For many utilities, warm weather is closely associated with the threat of algal bloom, the formation of toxic substances in source water that has been known to imperil drinking water supplies. Though the focus on this battle has begun to cool for the year, the U.S. EPA has recently released a suite of materials meant to help utilities combat harmful algal blooms (HABs), including FAQs, guidance on determining a bloom’s potential for harm, and a list of laboratory resources that can aid in analysis. Utilities can use these tools to develop a cyanotoxin monitoring program, communicate potential health risks to the public, and address HAB outbreaks.

“These materials were released … with the goal of supporting state recreational water body managers protect public health from HAB outbreaks and harmful levels of cyanotoxins,” an EPA spokesperson said. “States expressed interest in the EPA developing tools and information materials to support the development of state cyanotoxin monitoring programs, communicating potential health risks to the public, and addressing HAB outbreaks.”

Though the summer, which introduces the warm water temperatures that promote algal growth, brings these risks to the top of utility minds, it is never a bad time to take fundamental steps that can improve a community’s safeguards against cyanotoxins in the long run.

“It is critical to take actions to prevent occurrence of HABs in water bodies, including those that serve as drinking water sources, in the first place,” said the spokesperson.

Among its resources and advice, the EPA recommends addressing nutrient pollution, adopting numeric nutrient criteria into water quality standards, taking treatment measures, and more. The tips were compiled with the help of a focus group, comprised of six states and staff from the Association of Clean Water Administrators.

The materials offer critical tips on managing algal bloom through its lifespan, from preventing them in the first place to addressing them once they’ve formed.

On reducing the occurrence of algal bloom, for instance, the agency points visitors to a wealth of supplies, mostly focused on reducing nutrient pollution. There is information on producing a dual nutrient criteria fact sheet, arriving at nutrient targets, nutrient pollution policy and data information, and a water quality standards handbook.

“Addressing nutrient pollution … can help reduce the occurrence of cyanobacterial blooms,” the agency writes. “As a long-term strategy, states may consider adopting numeric nutrient criteria and/or numeric interpretations of a narrative nutrient criterion into their water quality standards.”

Helping communities deal with blooms once they are detected is an entirely different matter. For this challenge, the EPA has compiled a six-point plan. It recommends: 1) Analyzing samples to determine whether the bloom is producing cyanotoxins that are potent enough to cause harm; 2) Notifying partners at the local and state levels to coordinate a response; 3) Issuing public notifications; 4) Weighing the treatment options; 5) Monitoring and sampling source water to update the notifications as necessary based on changing cyanotoxin levels; and 6) Reporting suspected blooms to the One Health Harmful Algal Bloom System.

All told, the agency has compiled a wealth of resources that are designed to help water systems manage the threat of HABs from beginning to end. Though summer is coming to an end, it’s an effort that will be appreciated.