Residents will need to keep a lid on it if they want to see fewer rodents in their homes and neighborhoods.

The city has mounted another offensive in the “war on rats” with the announcement that it will begin distributing 64-gallon rodent-resistant trash carts to residential units that receive trash service from the city. The carts, provided by Russell Disposal, will be given out (as in for free) beginning next month.

The carts, however, are only effective if people use them correctly, which includes making sure they are tightly sealed. The city has undertaken a number of steps to reduce the rat population, such as attempting to sterilize them through treated bait traps and stepped-up enforcement of dumpster licensing, use and maintenance.

On that last note, residents have a right –and an obligation- to act as unofficial enforcement officers. We’ve all seen the overflowing dumpsters crammed high with trash like a precarious house of cards. Even worse is when the dumpsters are full to the point where trash bags are left on the ground so they are just “dumpster adjacent,” creating a literal buffet for hungry vermin.

To take a cue from crime reporting, if you see something, say something. This is one of those times when it’s OK to rat someone out.

The city has a duty to keep Somerville as clean and rodent-free as possible, but so do the residents who, knowingly or maybe not, contribute to the problem by not taking simple steps to help curb the rodent population. The public will have a chance to hear from the city’s Rodent Action Team, which will provide an update on its efforts during a public hearing at 6 p.m. Wednesday, June 4, in the Aldermanic Chambers at City Hall, 93 Highland Ave.

Cheese and crackers, for obvious reasons, will not be served.