A. Algae gets a bad rap and while there are certainly times it deserves it, other times it doesn’t. In fact, algae are a natural part of lake ecosystems, often microscopic and in low enough concentrations that we don’t even notice them, with many posing no risks to people and animals. Not only are they naturally present but they are extremely important to lakes. They form the base of aquatic food webs, oxygenate the water and turn nutrients into organic matter.
But as the saying goes, there can be too much of a good thing, and it is no exception when it comes to algae. Hot weather, calm and shallow water, sunlight and an increase in nutrients, most notably phosphorus and nitrogen, help create the perfect conditions for rapid algae growth, which can tip the balance from good to bad. Algal blooms can form, and while not all are harmful, those that are made up of toxin-producing cyanobacteria can make the water unsafe for people, pets and wildlife. When large algal blooms die and decompose, it can deplete oxygen levels in the lake, impacting aquatic life including fish kills.
To help keep the natural balance in your lake and help prevent tipping the scales from good to bad, it’s important to reduce the amount of nutrients entering your lake. There are actions you can take on your own property:
- Make sure your septic system is functioning properly
- Have a buffer of native plants on your property along your shoreline. This will filter contaminants from runoff before they enter the lake; it will also shade and cool the water.
- Avoid the use of fertilizers and pesticides
- Use rain barrels or create a rain garden to capture rainwater from your eaves
- Don’t bathe in your lake
If you suspect a harmful algal bloom, you should report it. Who you report it to depends on your province or territory, but you may wish to contact your Ministry of Environment, Environmental Public Health or your local health authority.
