Coronavirus level in Ottawa wastewater still rising, but at slower pace: experts

The level of COVID-19 in Ottawa's wastewater is still going up, but it's increasing at a slower rate than in previous weeks, experts say.

'A lot of virus moving around in Ottawa right now,' doctor says

Ottawa's COVID-19 viral signal in wastewater is still increasing but at a slower rate, experts say. Pictured: a sampler used to collect wastewater at McGill University. (Sarah Leavitt/CBC)

The level of COVID-19 in Ottawa's wastewater continues to rise, but is increasing at a slower rate than in previous weeks, experts say.

"We are unfortunately not seeing the turn in the wastewater curve yet, but the rate of the rise is slowing," said Dr. Vera Etches, Ottawa's medical officer of health. 

The level remains very high, Etches added in a media scrum that took place shortly after she released a statement strongly urging people to take their upcoming holiday weekend gatherings outside

Wastewater researchers didn't post an update for about a week as they adjusted 10 months worth of daily numbers. Data up to Sunday is still showing record daily readings and a weekly average roughly 15 times higher than it was in early March.

Researchers measuring and sharing the amount of novel coronavirus in Ottawa's wastewater have found it setting records for daily readings and the weekly average. The most recent data is from April 10. (

Dr. Doug Manuel, a physician and senior scientist at The Ottawa Hospital, echoed Etches' assessment of recent wastewater data.

"What we're seeing is a lot, a lot — two lots — of transmission," he said. "A lot of virus moving around in Ottawa right now."

That increases the likelihood of people at high risk of severe illness and hospitalization getting sick, Manuel added.

Wastewater is a key indicator of COVID-19 because it reflects a wide range of symptomatic and asymptomatic COVID-19 cases and nets quick results, Manuel said.

Tough to say how high hospitalizations will go 

COVID-19 hospitalizations have not risen as substantially in recent weeks as they did during the same stage of the fifth wave, but public health officials are keeping a close eye on the key metric.

"They will go up," Manuel said. "How high will they go? It's difficult to say."

Previous waves saw hospitalizations pick up pace quickly, and the potential for that to happen now remains, he added.

Etches said she is not currently considering invoking her powers to mandate measures such as public masking in Ottawa, citing current hospitalization rates that remain "very moderate compared to previous waves."

"I would want to see [new hospitalizations] increasing further as a sign that the severity is growing in the community." 

Etches said she and other local medical officers of health are meeting with Dr. Kieran Moore, Ontario's chief medical officer of health, on Thursday.

"What I'm interested in, of course, is what measures can be taken provincially to support what we see as a provincewide resurgence," Etches said. "It will be a dialogue and we'll see."


Guy Quenneville

Reporter at CBC Ottawa, originally from Cornwall, Ont.

Story tips? Email me at or DM me @gqinott on Twitter.