A fire station near Riverside South remained closed Monday night after a rat infestation was discovered over the weekend.

As many as 30 rats had nested outside and burrowed into Fire Station 37 on Earl Armstrong Road. The building was evacuated and firefighters were reassigned to neighbouring stations.

Early Monday afternoon, bait stations were set up outside the building walls, and rats could be seen scurrying in and out. Environmental engineers were onsite testing for air quality.

The station infestation is merely a sign of what some say is a growing rat problem in the capital, just in time for Canada's 150th birthday celebrations.

"I would say (Ottawa) Has a rat problem," said Robert Caron, branch manager at Orkin Canada's Ottawa location. "Is it out of control? I would say no, but if we don't take care of it today, it could get out of control."

Caron said rat calls to his company have gone up in the last couple of years. He cited the increased construction around the city as a factor, along with this past winter's mild weather and the city's green bin program, which was established a few years ago but has added another source of food for scavengers.

Caron has a few simple tips for avoiding rats at home:

City officials are looking into the larger issue. In February, city councillors Mathieu Fleury and Allan Hubley asked city staff for a report on rats in the city. Environmental services staff are preparing a report, but there's no timeline on its release.