Blue-green algae (Cyanobacteria) continues to affect the western shoreline of Hamilton Harbour

HAMILTON, ON – The City of Hamilton continues to monitor the presence of toxin-producing Blue-green algae (Cyanobacteria) affecting the western shoreline of Hamilton Harbour. 

Blue-green algae was first detected this season on August 3, 2018. As a result, Pier 4 beach was closed and public warning signs were posted at the affected beach and at the Bayfront boat launch. Information was also shared on the City of Hamilton website and with Hamilton Harbour stakeholders.

The City has installed bubblers on the docks at the Discovery Centre and the Bayfront boat launch to keep the water moving and discourage the algae from forming in large clumps. The City is also investigating the possibility of conducting surface cleaning to remove large floating mats of algae in the area over the coming days.

Contact with Blue-green algae should be avoided due to the potential health risks associated with it. The public is reminded to not enter and avoid contact with the water along the shoreline of Hamilton Harbour. 

Residents and visitors are advised to:

• Avoid contact with the water along the western shoreline of Hamilton Harbour, including while launching or trailering watercraft
• Wash off as soon as possible with clean water, if they come in contact with the water. Facilities for hand washing and rinsing off are available at the Bayfront Park public washrooms located at the east side of the Bayfront Park parking lot
• Keep pets out of the water
• Not consume any fish caught in these areas

Health Effects

Adverse health effects are mainly caused by drinking the water that is contaminated with blue-green algae toxins. Skin contact with blue-green algae contaminated water can cause skin irritation and itching. Exposure to blue-green algae toxins, if present in sufficient amounts, can cause headaches, fever, diarrhoea, abdominal pain, nausea or vomiting, skin rashes and mucous membrane irritation.

Anyone who has recently been in direct contact with the waters along the western shoreline of Hamilton Harbour and is experiencing headaches, fever, diarrhoea, abdominal pain, nausea or vomiting is advised to contact their primary care provider (family physician, nurse practitioner or walk-in clinic).

Quick Facts

• Blue-green algae (cyanobacteria) forms in shallow, warm, slow-moving or still waters
• Temperature fluctuations (i.e. increased water temperature), high nutrient loads, water mixing, slow-moving or still waters, provide the ideal environment for the proliferation of naturally occurring Blue-green algae
• Algae/vegetation in the water can give off an offensive odour as it dies and decays. This may be more prominent along the shoreline and in the various “nooks and crannies” (i.e. docks/boat slips)
• The Blue-green algae is expected to subside as the cooler weather arrives.  Locally, algal blooms have been observed until late November or early December
• The safety of Hamilton’s drinking water is not affected by this situation

Additional Resources

• For the current status of the water quality at Hamilton beaches visit www.hamilton.ca/beaches
• Learn more about blue-green algae