Harmful Algal Blooms

Harmful algal blooms can be identified through the following characteristics:

• Appearance: Scum or paint-like film on the water’s surface, often blue-green, but can also be brown, red, yellow or purple.
• Texture: Resembles spilled green paint or pea soup.
• Smell: Can emit a musty, earthy, or foul odour that can resemble the smell of rotting plants or fish.

What to Do if You Encounter a Harmful Algal Bloom

If you see something that looks like a harmful algal bloom in the water, it’s safest to assume it could contain toxins. You can’t tell just by looking if it’s safe or not. 

If you suspect a bloom, take these precautions:

• Avoid Contact
  • Do not swim or wade in the water.
  • Do not drink or ingest the water.
  • Refrain from eating fish caught in areas with suspected cyanobacteria. 
  • Be cautious while launching or trailering your watercraft; if exposed, rinse thoroughly with clean water.
  • Keep pets away from the water. 
• Report
  • Report suspected blooms by calling the City at 905 546-2489 (CITY).
    OR
  • Report to the Ministry by submitting a report online, or call the Spills Action Centre at 1-866-MOE-TIPS.
• Seek Medical Help:  
  • If you or your pets show symptoms after exposure, seek medical attention. 

What You Can Do 

Reducing the amount of phosphorus and nitrogen in waterbodies is crucial to preventing harmful algae blooms. Here’s how you can help protect Hamilton’s waterways and promote a healthier environment: 

• Minimize the use of fertilizers, pesticides and insecticides in your lawn and garden. Excess nutrients, especially phosphorus and nitrogen, can run off into waterways, fueling algae growth. 
• Pick up pet waste and dispose of it properly in the trash. Pet waste left on the ground can wash into catch basins, contributing to nutrient pollution. 
• Avoid hosing off sidewalks or driveways, and never sweep debris into a catch basin. These actions can introduce phosphorus and other pollutants into the water system. 
• Practice eco-friendly boating and marina habits. Never litter or release pollutants into the water, as these can worsen algae bloom formation.
• Report illegal dumping or pollution. If you see someone dumping litter, pet waste, or other pollutants into a catch basin, or if you notice areas where this has occurred, call the City’s 24/7 Contact Centre at 905 546-2489 (CITY). 
• Properly manage pool or hot tub water. Before draining, ensure no chemicals have been added for at least two weeks, and empty the water onto your property where the ground can absorb it, keeping it out of the stormwater system. 
• Take your car to a car wash instead of washing it in the driveway. Commercial car washes are required to properly manage wastewater to prevent sending pollutants directly into our local creeks and lakes. 

Hamilton Public Health Services closely monitors local public beaches for harmful algal blooms. If a potential bloom is observed or reported, water samples are collected from affected areas and tested for toxins. If harmful amounts of toxins are detected, Hamilton Public Health will close the affected beach to protect public safety. For blooms found at other recreational locations, Hamilton Public Health refers the issue to the Ministry of the Environment, Conservation and Parks and relevant City departments for further investigation and response. These departments coordinate additional water sampling and testing to help keep our community safe.

Drinking Water Safety

Hamilton’s drinking water supply has not been impacted by harmful algal blooms. Before reaching residents, drinking water undergoes multiple steps to ensure safety and quality. Hamilton Water conducts testing of both the raw lake water and the treated drinking water to ensure that no harmful toxins are present. Standards for drinking water quality are strictly regulated and enforced under the Safe Drinking Water Act. The City’s Drinking Water Quality Management System provides policies and procedures that ensure consistent delivery of clean, safe drinking water to our community. Learn more about the City’s Drinking Water Quality

Hamilton’s Commitment to Protecting our Waterways 

Restoring Hamilton Harbour’s health and natural heritage is a long-term, multi-faceted commitment involving many partners and remains a top priority for the City of Hamilton. Through efforts like the Clean Harbour Program and the development of the Watershed Action Plan, the City is working to improve and protect water quality and water quantity within the City’s watersheds and Hamilton Harbour. An important part of the plan is to prevent and reduce conditions that promote algae growth. To learn more about the Watershed Action Plan visit www.hamilton.ca/watershedactionplan.