Mayor Rahm Emanuel is adding reinforcements in Chicago’s never-ending war on rats.

The mayor’s 2018 budget will add five more rodent control crews—for a total of 30—and provide $500,000 in additional funding to purchase more black garbage carts.

Already this year, the city has responded to more than 23,400 requests to replace lost, stolen or damaged carts. More than 10,000 black garbage carts and more than 3,000 blue recycling carts have been repaired since Jan. 1, 2016.

For more than a year now, South Side Ald. Howard Brookins (21st) has been after the city to explore “options for procuring stronger garbage carts” more resistant to “aggressive squirrels” he complains have been chomping their way through all too many of Chicago’s 96-gallon garbage carts.

Spillover from broken or over-flowing carts create a breeding ground for rats.

The $1 million investment will be included in the 2018 budget that Emanuel is scheduled to unveil next week

It will be paid for by additional savings generated by and personnel freed up from the switch from a ward-by-ward system of garbage collection to a grid system.

“These critical investments in rodent control and garbage carts allow us to continue to provide the best possible service on behalf of residents,” Emanuel was quoted as saying in a press release.

Streets and Sanitation Commissioner Charles Williams said the additional investment will help ensure that “every report” about rats is “addressed within five days or less.”

The city has already achieved that five-day standard, even after fielding 39,000 rat abatement requests this year, the commissioner said.

“The rodent battle will only benefit from the investment in garbage carts which helps ensure that residents can swap out any damaged carts for a new or refurbished one in a timely manner,” Williams was quoted as saying.

Chicago has tried just about everything to control a burgeoning rat population fueled by a construction boom and a mild winter. None of it has worked in a city seemingly overrun by rodents.

Prior efforts have included include everything from dry ice, rat poison and cart repairs to coyote management, adding ten baiting crews and public education.

The mayor’s 2017 budget also resurrected the stand-alone bureau charged with marshaling the city’s war on rats.

Earlier this year, City Hall tried something old and something new: a poison designed to make rats infertile and dry-ice that produced promising results in parks and medians before the city was forced to stop the rat-suffocation experiment after learning the dry ice had not yet been approved by the U.S. Environmental Protection Agency.

The poison is called “Contrapest.” It is being tested for six months at a waste transfer station at 34th and Lawndale, where 25 “bait boxes” will be installed, each equipped with feeding tubes that encourage rats to take poisonous bait.

If it works as advertised – by rendering rats infertile unable to breed – the poison could become a “regular method used in other enclosed and contained areas” that serve as breeding grounds for rats.

And now that the EPA has signed off on dry ice, the city will start using it again to control the burgeoning rat population in Chicago parks.