CHICAGO (CBS) — Coming Monday, the city will begin the final phase of collecting garbage on a more efficient grid-based system, rather than ward-by-ward.

WBBM Newsradio Political Editor Craig Dellimore reports the money saved from the grid-based system will help fund citywide curb-based recycling.

However, the savings from the switchover is less than a third what Mayor Rahm Emanuel predicted two years ago.

“If somebody has a better way to find $60 million in savings, the door is open, the suggestion box is open,” the mayor said in August 2011 of opposition from aldermen who wanted to stick to a ward-by-ward collection system that gave them more control over where and when to pick up trash.

At a Streets and Sanitation facility in the Pullman neighborhood, Emanuel said Thursday that wards on the Far South and Southwest Sides will be the last to begin using the grid-based system.

The city will save $18 million a year by collecting garbage on a precise grid system, instead of crews having to follow the often labyrinthine boundaries of the city’s wards, according to Emanuel.

Two years ago, when the mayor first announced plans to shift to a grid-based system, he predicted the annual savings at $60 million – more than three times the savings he touted on Thursday.

Many aldermen have been wary of the switch to a grid-based system, as it will reduce their control over a service important to their constituents.

They feared they would lose the ability to ask for special trash pickups when needed, but the mayor touted that politics will be taken out of garbage collection decisions, while the move will also allow the city to expand curbside recycling to every ward.

“People are enthusiastic about finally having recycling citywide in the city, and this is a byproduct of doing garbage collection without politics, but with efficiency as the model, and the goal,” he said. “We had debated about the notion of taking politics out garbage collection in the city of Chicago for over a decade, and this day marks the end of the debate.”

Ald. Anthony Beale (9th) who was among aldermen who once criticized changing to a grid-based system, said he’s happy ward superintendents will stay on the job.

“That was one of the big concerns, how are we gonna address the specials when we have lots that need to be cleaned, when we have bulk pickup that needs to be done,” he said. “So our ward superintendents will still have the ability to make sure that those specials are taken care of, and the commissioner’s assured us that we’re going to have the resources to make sure they get taken care of.”

Streets and Sanitation Commissioner Charles Williams said there have been some bugs to work out in other wards when making the changeover to the grid-based system, but so far so good.

“Complaints are about the same. We don’t see a spike in complaints. In fact, the resident actually shouldn’t notice the change. The only change with the residents is the day of service,” he said.

With the entire city on a grid-based system starting next week, citywide curbside recycling should also be in place by the end of the year.