Marysville has attracted more than its share of undesirables. Many live along the banks of the Yuba River, which flows between Marysville and the unincorporated town of Linda. Walking along the levee is hazardous, as they are known to rob and assault passersby.
Do not give anything to the bums; it's like feeding animals in the National Parks. It makes them dependent upon handouts. If they can no longer obtain food, money, or shelter here, then they'll migrate to another town and become someone else's problem.
Teenage boys on their dirt bikes and ATVs pose a serious threat to pedestrians, especially along the levee. All motor vehicles are banned from the levee, but that doesn't stop them for a minute.
The ATV/dirt bike riders are extremely aggressive, with no regard for their own safety or anyone else's. If you observe one, report it to the police. Maybe someday they'll catch some of them.