Higher-than-average E. coli levels in a water sample from Thursday morning caused the City to issue an advisory against swimming at Westboro Beach Friday.
Donna Casey, a program and project management officer at Ottawa Public Health, said significant rainfall Wednesday could’ve played a role in the unusually high rate of harmful bacteria.
She said these incidents are usually due to sediments and bird droppings on the beach getting washed into the water, mentioning that geese are “everywhere” along the river around this time of year. Rainfall also causes sewage systems to overflow into the river.
Environmental health students take samples at Ottawa beaches every morning, said Casey. It takes 24 hours for lab results to come back.
The reading posted on the public health site Friday was 1,000 units per 100 ml of water.
If E. coli levels reach more than 200 per 100 ml of water for one day, or 100 per 100 ml of water for two days in a row, a red flag will be raised for swimming.
All Ottawa beaches were closed June 25 and 26, with Mooney’s Bay and Petrie Island beaches closed until June 28. It was reported 324 million litres of raw sewage and untreated water had flowed into the Ottawa River on June 24.
Casey said when E. coli levels are above 200 parks and recreation staff are present at beaches and advise visitors of heightened risks for skin, eye, ear and nose infections or gastro-intestinal issues if water is swallowed, “especially for young children who often get mouthfuls of water,” said Casey.
She said the low chance of rain over the next few days should mean the water will be safe for swimming by the weekend.
