OTTAWA -- It was a long wait in the snow for hundreds of front-line workers seeking a COVID-19 vaccine on Saturday.

The Ottawa Hospital says the people in line were hospital and community-based health-care workers, staff and essential caregivers from long-term care homes, and staff from high risk retirement homes. They had been called in to receive their shots at the hospital's clinic at the Civic campus, but ended up waiting more than an hour in line in heavy snow, despite having appointments.

In a statement to CTV News Ottawa, the Ottawa Hospital said the lineup was the result of a booking error.

"The Ottawa Hospital’s vaccine clinic experienced a minor booking issue (Saturday) morning which caused the line up to be longer than usual," the Ottawa Hospital said. "Appointments are continuing as scheduled."

The hospital's Civic campus is one of the nine sites identified by the City of Ottawa for vaccination clinics, but it is the only one that is currently up and running. The hospital has been vaccinating people on site since the first doses arrived in December.

Speaking on CTV News at Six Saturday evening, medical officer of health Dr. Vera Etches said Saturday's issues are not a preview of long lines to come at COVID-19 vaccination clinics in Ottawa.

"The lineup (Saturday) was out of the ordinary. The Ottawa Hospital has been operating their vaccine clinic since December without that kind of glitch – it was more of a technical problem this morning," said Etches.

Ottawa's top doctor says Ottawa Public Health will use an appointment system to book COVID-19 vaccines this spring and summer.

"So what we're expecting is to rely on appointment based clinics, for the most part. So that then enables people to have the set time and avoid a lineup."

There will be eventually be seven community clinics and additional clinic at the Queensway Carleton Hospital. The timeline for opening community clinics is based upon vaccine supply, city officials have said. Once enough supply is available, the sites can be opened with 72-hours' notice.

This past week, Ottawa received 9,360 doses of the Pfizer-BioNTech vaccine and 4,000 doses of the Moderna vaccine. 

Pop-up community clinics for seniors 80 and older, as well as adults receiving chronic home care will launch in the Ledbury, Heron Gate, Ridgemont, Emerald Woods, Sawmill Creek and Riverview communities starting March 5. More details on these clinics will be available on Monday.

Ottawa Public Health is currently making automated phone calls to reach out to home-care patients to instruct them on how to receive a COVID-19 vaccine.

With files from CTV News Ottawa's Josh Pringle