A lot of heavy drug use in the bush around the creek. Desperate drug addicts don't care who they hurt to get their next fix. The Methadone clinic is about 200 meters from the creek down there and the bike path that follows the creek makes a great highway for people that want to stay off the main street and out of sight. The bush surrounding the creek is a Rabbit's warren and there are increasingly bigger tent cities growing in it. Those tent cities attract drug users and those violent people that want to prey on drug users.
If you look at the link below the problem is severe enough that the city has converted mailboxes to accept used needles. 3 of the locations are along the creek.
https://www.oshawa.ca/residents/public-space-harm-reduction-needle-drop-boxes-.asp
And its not just your stereotypical junkie either. Our former neighbour who was doing well in life, owned her home and had at least 12 yrs into a mortgage that we lived next to her, worked downtown in the TD IT dept. Died of an OD days after getting out of rehab. She wasn't a violent predator, but I'm sure she had violent predators at her house by the looks of some of the characters I saw before we moved.