Beach season comes to an end at Ottawa's four public beaches

A no-swim advisory sign is seen at Mooney's Bay Beach Monday, July 31, 2023. Ottawa Public Health is investigating a possible harmful algae bloom. (Aaron Reid/CTV News Ottawa)

It was a red flag summer at Ottawa's public beaches, with one beach closed approximately one out of every three days this summer due to high levels of e-coli in the water.

Sunday was the final day lifeguards will be on duty at Ottawa's public beaches this summer, after 72 days of supervised swimming.

Statistics on the Ottawa Public Health website shows there were 23 days with "swimming not recommended" advisories at Mooney's Bay Beach this summer. Four of those days were July 31 to Aug. 3, when health officials advised people not to swim due to a possible algal bloom in the Rideau River at the beach.

No swimming advisories have been issued on 20 days at both the Petrie Island East Bay and Petrie Island River beaches this summer.

Health officials issued no swim advisories on 13 days at Britannia Beach this summer. A no swimming advisory was issued for Britannia Beach on the final day of the beach season on Sunday.

Water samples are collected daily from Ottawa's supervised beaches and tested for the presence of e-coli bacteria.

"When elevated levels of e-coli are detected in the water, it is more likely that other disease-causing organisms are also present. These organisms can result in skin, ear, throat or gastro-intestinal illnesses," Ottawa Public Health says on its website.

The high number of no-swim advisories at the four beaches comes during a very wet summer in Ottawa.  Ottawa received 142 mm of rain in July and 106.1 mm of rain in August, with five days of at least 20 mm of rain this summer.

Here is a look at the swimming not recommended advisories issued for each beach over the last four years.

Britannia

• 2023: 19 days
• 2022: 11 days
• 2021: 5 days
• 2020: beach closed

Mooney's Bay

• 2023: 23 days
• 2022: 5 days
• 2021: 7 days
• 2020: 10 days

Petrie Island East Bay

• 2023: 20 days
• 2022: 17 days
• 2021: 29 days
• 2020: 36 days

Petrie Island River Beach

• 2023: 20 days
• 2022: 6 days
• 2021: 5 days
• 2020: 13 days