CHICAGO (CBS) — A group that advocates for bicyclists and pedestrians is offering evidence that it says bolsters Mayor Rahm Emanuel’s case for speed cameras in Chicago school zones.

As WBBM Newsradio’s Regine Schlesinger reports, last T hursday afternoon, the Active Transportation Alliance clocked cars going through the intersection of Cortez and Humboldt drives in the park of Humboldt Park. Just over 100 feet from the intersection is a popular soccer field.

LISTEN: WBBM Newsradio’s Regine Schlesinger reports

The alliance says during a 10-minute period in the mid-afternoon, most of the 100 vehicles that passed were going within 5 miles of the 30 mile an hour limit, but, it also found a number going 40 miles or more. Those included sport-utility vehicles, cars, and even a school bus.

In the video, the group points out that most of the vehicles were abiding by the speed limit. But the most egregious offenders were plowing through the intersection as fast as 46 mph. The school bus was going at 45.

The group says a person hit by a driver going 20 miles per hour has a 90 percent chance of surviving, while someone hit by a driver doing 40, has only a 10 percent chance of survival.

The Alliance is urging Chicagoans to urge their aldermen to vote for the proposed speed cameras near Chicago schools. The City Council Committee on Pedestrian and Traffic Safety signed off on the speed camera plan last week, sending the measure to the full City Council, which will take up the proposal on Wednesday.

The ordinance would use existing red light cameras and vans equipped with cameras to catch speeders during certain hours outside schools and parks. Critics have said the plan is really about generating revenue, and that the cameras would blanket an exceptionally vast part of the city.

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