For South Boston residents, spotting a rat on the sidewalk or darting through an alley has become an increasingly common — and unwelcome — sight throughout the neighborhood.

According to City Councilor Ed Flynn, complaints about rodents are now among the most frequent concerns he hears from residents. “And I believe the situation is getting worse.”

He’s even heard of rats getting into people’s houses or apartments!

For Flynn, who sees rats almost daily, the issue extends beyond an unpleasant nuisance.

“Pest control and rats in our neighborhood — it’s not just a public health issue; it’s also a public safety issue,” he said. “And a significant quality of life issue.”

To deal with this ever-increasing problem, Flynn said public awareness and education have to be part of the solution. “If we do a better job on public awareness and communication, we can solve a lot.”

Flynn also said stronger and stricter code enforcement is another important part of addressing the rat infestation.

“I think we need overall change in how we do pest control in Boston,” he said. “There should be a standalone city department that specifically deals with pest control. I think it’s that serious of a problem.”

For Flynn, the issue comes down to the city’s basic responsibility to its residents: “I do believe we need to prioritize pest control management in Boston because right now we’re not doing it.”

What’s causing the problem? Flynn points to several factors, including ongoing construction and the way people put out their trash for collection.

Food left in improperly secured trash provides sustenance for rodents. “You just can’t put a trash bag on the street that has food inside it,” Flynn said. “That’s a recipe for disaster.”

Boston requires residents to wait until after 5 p.m. the evening before their collection day to bring trash containers curbside. Residents are required to provide their own black or gray trash containers with secure lids, and all trash must fit inside the barrel with the lid closed.

Overflowing trash or bags left on the street are considered code violations.

For buildings with landlords and tenants, the landlord is responsible for providing trash containers that meet the city’s requirements. Landlords are also responsible for creating a waste management plan and educating tenants about their responsibilities as residents of Boston.

Flynn said better public education about those rules could make a difference. “We can’t assume people know what the rules are.”

Flynn believes composting could help reduce the amount of food waste available to rats.

“I believe composting has to be part of the solution,” he said.

Boston currently offers a curbside food waste collection pilot program for buildings with six units or fewer. The program provides participants with a composting container with a secure lid, which is picked up by the city on a regular schedule.

Residents who do not qualify for the curbside pilot program, or who are on the waitlist, can use Project Oscar, the city’s 24-hour community food waste program. In South Boston, a Project Oscar bin is located on West Broadway and is designed to be rodent-resistant and locked. The bins accept food waste including meat, bones, dairy, and fish.

Flynn suggested a public awareness campaign explaining the city’s trash rules and regulations and making that information easily accessible through social media.

He also emphasized the importance of making sure residents — particularly people who may be new to the neighborhood — understand how and when to put out their trash. “It seems simple, but it’s often overlooked, and I think we have to get back to basics.”

Flynn urged residents who see rats to report them immediately to the City of Boston through the 311 app. When reporting a sighting, residents should be as specific as possible about where and when they saw the rat and the circumstances surrounding the sighting.

Residents can also contact Flynn’s office with concerns.

Addressing the problem will require a combination of better public awareness, proper trash disposal, composting, code enforcement, and a greater citywide focus on pest control.

“We won’t ever solve the problem,” Flynn said, “but we can significantly reduce rats in our neighborhoods.”