Her right hand protected by an old plastic bag, Donna Devlin carefully reaches into a shallow sewer basin in her driveway, and drags out a dead rat the size of her forearm.

It's the latest casualty in a war that Devlin and her neighbours in the Danforth-Woodbine area of Toronto say they've been fighting, on and off, for two decades — a war that, in the past couple of years, has become a losing battle.

"We used to use the rat traps, but they don't seem to be going for the traps anymore," she said. "The last time we put one there, the rat came out, he looked at it and he just flipped it right down the drain. And he just looked up at us."

The Gledhill Avenue resident said she's recovered — dead or alive — scores of rats on her property over the past 10 years alone. But the rat population has been escalating in the past two or three years, she said, as nearby condo developments and other construction projects drive the rats from their underground lairs onto — and under — quieter residential streets.

Devlin's driveway is crumbling in places because, she maintains, tunneling rats have undermined its foundation.

Dee Paul, of Gledhill Avenue, says rats recently excavated a warren of tunnels underneath her concrete basement floor. She's had to spend $500 on an exterminator but the problem has persisted. (Rob Krbavac/CBC)

But Devlin and her neighbour, Dee Paul, said the rats aren't just showing up outdoors. They're making their way into homes, coming up through toilets, dryer vents and even through quarter-sized cracks in walls.

Paul said the rats tunneled so extensively under her concrete basement floor that she had to call in a contractor to excavate it.

"We poured buckets and buckets of cement into these tunnels and we didn't have the problem for a while, but now they're back."

The warrens on Devlin's property are so extensive that her driveway has started to cave in. Both women said their neighbourhood is especially hard hit by infestations, but city numbers show they are not the worst-off ward in Toronto.

In the past ten years, their Ward 19 Beaches-East York ranks number three city-wide for reports of rats, with 450 complaints since 2009.

The only wards with more, Parkdale-High Park and Davenport, had 547 and 528 complaints respectively.

Donna Devlin stands beside a wire mesh cage that an exterminator installed over her dryer vent, one of the entryways typically used by rats trying to get into houses. (Rob Krbavac/CBC)

From 2017 to 2018, the number of rat complaints in Devlin's area nearly doubled, from 39 to 70 last year. This year, the ward is on pace to record almost 100 rat complaints by the end of 2019, which would be the most in any ward going back to 2011.

Local councillor Brad Bradford (Ward 19 Beaches-East York) said the city is in the midst of a Toronto-wide study on the extent of the city's rat problem.

That report is due by the end of the year.

Paul said it's already time for the city to send in the cavalry: exterminators.

"I would really like to see them bring back the baiting program because when they did the baiting, the rat problem went away, or at least it went underground," she said.

Both Bradford and city spokesperson Brad Ross said the city will only get involved under specific circumstances — when the infestation is on city property, for instance, or when commercial properties regulated by the city such as restaurants, are involved.

And while Devlin and Paul would like to see poison bait laid out in sewage pipes in the neighbourhood, Bradford said that approach rarely works.

"The city has tried baiting in the past in some of our sewers and it hasn't been terribly effective," he said. "It goes back to making sure we're not having food sources in places where rats can come in and get fed. If you take away the food source, that's the best means of pest control."

Local Coun. Brad Bradford says the city is in the midst of a major study on Toronto's rat problem. (Mike Smee/CBC)

In most circumstances, homeowners are responsible for controlling pests on their property, according to the city's website.

In Devlin's case, that meant a $700 visit from a pest control company, which sealed potential entrances to her home, like a laundry vent, with special metal mesh cages.

City spokesperson Ross said the best defence for homeowners is a good offence.

"Whether it's doing things like making sure you seal your green bin, reducing clutter around the property, eliminating fruit fallen from fruit trees that you might have in your backyard, or pet food left outside, tall grass where they can hide — those types of things," he said.

In the meantime, Devlin said she'd even stomach a tax increase if it meant the city would react more proactively to rat populations plaguing private properties.

"It's scary," she said. "I'd rather be doing other things: gardening, housework, working. It's creepy."