The city's finance department will give scofflaws a two-week window before it starts mailing out tickets, Ald. John Arena (45th) said. View Full Caption The Expired Meter.com

CHICAGO — Drivers in downtown Jefferson Park can expect to see cameras mounted this week above the patchwork of intersections where Foster Avenue, Milwaukee Avenue, Central Avenue and Northwest Highway converge, city transportation officials announced Thursday.

The cameras will be activated Friday, but the city's finance department will give scofflaws a two-week window before it starts mailing out $100 tickets, so as allow motorists time to acclimate to the changes, according to the announcement.

One set of cameras will face eastbound traffic on Foster at the intersection of Northwest Highway, officials said. The other rig will catch southbound drivers along Central Avenue at Milwaukee.

Eight new traffic light heads will accompany the new hardware at both intersections, plus a left-turn-only light for drivers turning onto Gettysburg Street from Milwaukee, officials said.

New crosswalk timers have been installed at all five intersections, and new signs have been posted to warn drivers about the cameras.

The cameras will target drivers at these two intersections.[Google Maps]

The additions are part of a shakeup of the city's red-light camera program announced earlier this year, after a study by the Northwestern University Transportation Center suggested that the cameras weren't effective in reducing crashes at some intersections.

While city transportation officials agreed to take down cameras from five intersections around the city, they proposed installing new ones above five other traffic choke points, including the one in Jefferson Park.

The new locations were picked "based on traffic volume, the design of the intersection, a high number of angle and turning crashes and a low number of rear-end crashes," officials said in March.

The 104-page Northwestern study compared before-and-after crash data at 85 intersections with red-light cameras to 103 intersections that were not monitored by cameras.

It concluded that the city's red-light camera program should continue because it led to a 19 percent reduction in serious side-angle and turning crashes, a 10 percent reduction in injury-producing crashes and a measurable “spillover effect” that improved safety at intersections without cameras.

But rear-end crashes increased 14 percent at intersections with red-light cameras as compared with those that did not have the cameras.

"Federal traffic safety research has found that side-angle crashes cause five times more damage than rear-end crashes as well as being more likely to cause fatalities and serious injuries," according to a statement from Chicago transportation officials.

The cameras became a major issue in the 2015 mayoral race, with Cook County Board Commissioner Jesus "Chuy" Garcia vowing to remove all the red-light cameras if elected.

A few days after Garcia's announcement, Emanuel announced he would remove 50 cameras at 25 intersections and give red-light violators a chance to attend traffic school in lieu of paying $100 for a first violation.

In all, Emanuel has removed 78 red-light cameras at 39 intersections since taking office, leaving 306 red-light cameras at 151 intersections.

Ald. John Arena wrote in a Thursday Facebook post that he would "continue to be a strong voice for reforming the red light camera program."