A serious pedestrian crash at a roundabout in Kitchener in October has led to demonstrations, debates and changes, and renewed the focus on safety.

The collision occurred at Homer Watson Boulevard and Block Line Road, where an estimated 35,000 vehicles pass through each day.

Some people had been concerned even before the roundabout was installed that moving away from a signalized intersection could jeopardize pedestrian safety.

Then on Oct. 7, 16-year-old Cassi Lam was struck by a Grand River Transit bus at the roundabout as she was walking to school and seriously injured.

Waterloo Regional Police Const. Tim Boniface was one of the first emergency responders on the scene and described what he saw.

"Her head snapped and hit the windshield so damage itself to the bus isn't all that extensive but there is a lot of mass behind that which can cause fairly severe injuries."

Cassi's parents rushed to the hospital, and her mother Gail says "As parents when we saw Cassi in the trauma unit my husband, a grown man, just broke down. I stood in shock."

Family lawyer David MacDonald says the Grade 11 student now requires extensive care and ongoing treatment.

"She's got a physiotherapist...an occupational therapist has been involved, she'll have more to do with the cognitive remediation later. A neuropsychologist has been involved as well and we have an appointment lined up for a neurologist in the New Year."

The Lam family has notified those involved that it will be seeking damages. The planned lawsuit alleges "This patently unsafe traffic circle has been built with tax dollars from local citizens without taking appropriate safeguards to ensure pedestrians and traffic would be able to safely use the intersection."

The incident has led to a number of people calling for changes to the region's strategy when it comes to roundabouts.

Gail says "No child's life should ever be compromised because of any amount of money and we don't want anyone else's child to go through this, they may not be lucky enough to come through the way Cassi has."

Friends and schoolmates say they feared something like this might happen from the day the roundabout opened in late August.

In the days after she was struck, Cassi's fellow St. Mary's High School students and their parents rallied at the roundabout.

Student Diana Cantor told CTV News at the time "Drivers don't pay attention and neither do kids, so it's both their fault. It's dangerous, I find it very dangerous."

Student Rachel Jacquot said "I don't want to wait for somebody else to die before they put something in that's safe."

Changes have been made, including lowering the speed limit and changing the signage at the roundabout from a yield to a stop for pedestrians. Additional changes are being considered.

But MacDonald questions if it's enough to improve safety and there have already been calls to hold off on construction of new roundabouts.

MacDonald says "Schools, kids, roundabouts, I don't think that they mix."

Coming up in part three: Looking ahead to the future of roundabouts in Waterloo Region.