Chicago is following in the footsteps of several other big cities using dry ice as a weapon in the war on rodents.
City officials began experimenting with dry ice last month, after the program’s pioneer of Boston and then New York City, which launched its test program in May, both found success in using the method to reduce their rat population.
Under the pilot program, crews will play dry ice directly into a rat burrow before covering the hole. When the ice melts it turns into carbon dioxide and suffocates the small animals. The dead rats then decompose in the burrow and are out-of-sight.
The dry ice method is cheaper than traditional methods, and many believe it to be more humane and environmentally friendly.
Preliminary results being tested at three Chicago parks showed the method successfully eliminated more than 60 percent of rodents when an area was treated, city officials said.
If the pilot program continues to be a success for Chicago, city officials say it could be expanded next year.
City officials urge residents who have a rat problem to call 311 for a crew to come out and use the dry ice method in the burrows.