Every summer, we look forward to certain things: creemees, sunny days at the beach, and cooling off in Lake Champlain.
But each summer, cyanobacteria algae blooms make an appearance in Lake Champlain and the surrounding bodies of water.
You’ve probably heard about cyanobacteria algae blooms. But what are they, and what causes them?
Cyanobacteria, or blue-green algae, are photosynthetic bacteria that occur naturally in waters used for recreation, such as swimming and waterskiing.
Certain environmental conditions, such as elevated levels of nutrients from human activities (e.g., nitrogen and phosphorus), warmer temperatures, still water, and plentiful sunlight can promote the growth of cyanobacteria to higher densities, forming cyanobacterial blooms. When the bloom is formed by a toxin-producing bacteria, it is generally referred to as a harmful algal bloom.
These blooms are considered harmful due to the production of irritants and/or toxins, called cyanotoxins, which can pose health risks to humans and animals.
Swimming or wading in water with cyanobacteria may cause minor skin rashes, sore throats, diarrhea, stomach problems, or more serious health problems. Children and pets are at higher risk of exposure because they are more likely to play near the shoreline and drink water while swimming. Pets can also lick and swallow cyanobacteria that may be caught in their fur.
A rain garden allows the rain water to pool for a short period of time in the garden. As rain from rooftop areas or paved areas soaks into the ground, the water is cleaned by the plants and the soil microbes in the soil.
Learn about planting a rain garden.
No matter where you live, if you use fertilizer on your lawn, it could be contributing to algal blooms on Lake Champlain. Rain and stormwater will often wash the fertilizer from your lawns into storm drains, leading directly to Lake Champlain.
Read about limiting your fertilizer.
One easy way to help protect rivers, lakes, and streams is to redirect your roof gutters and downspouts away from hard surfaces such as your driveway and collect the rainwater in mosquito-proof containers known as rain barrels.
Learn how to install a rain barrel.
It is not possible to tell if a bloom contains harmful toxins just by looking at it. Only laboratory tests of water samples can confirm whether a bloom is toxic.
General health effects caused by exposure to cyanobacteria cells (not their toxins) include:
Additionally, some cyanobacteria may produce harmful compounds called cyanotoxins. When these toxins are swallowed in large amounts, they can cause the following health effects:
Cyanobacteria toxins can also cause illness and sometimes death in pets and livestock. Possible symptoms animals may show after being exposed to a toxic bloom include: