WATERTOWN — The City Council on Monday unanimously passed a law that requires e-bike and e-scooter riders to wear helmets and to not ride on sidewalks.

The city put together the new law in response to reports of e-bikers riding erratically and causing accidents and near misses.

The city embarked on an education and promotional campaign before fines would be implemented. The new law took effect immediately after passage.

Violators will be given a $150 fine for a first offense and $300 for any subsequent offense within 18 months. The new law also makes a change that allows children 12 and younger to ride their traditional bikes on sidewalks.

Before the vote, council members praised the new e-bike law and stated it was needed. The law is going after repeat offenders and those who don’t ride safely, they said.

“I’m happy that staff has put this together; we’re going to make this happen,” Councilman Benjamin P. Shoen said.

Three people spoke at a public hearing about the e-bike law before the vote.

Resident Patricia Oatridge said she’s against the helmet requirement.

“I’m 59 and I should make a decision if I use a helmet,” she said.

She also criticized the city for not having enough bike lanes, mentioning that a vehicle hit her while she was operating her scooter last year.

Councilman Robert O. Kimball responded by saying helmets are basic safety equipment, likening them to seat belts.

“Certainly, we should try to increase bike lanes, but for right now, we’ve got what we’ve got. We need to keep people on the road because they have motor vehicles,” he said.

While he supports the law, LeRay Street resident Robert Schorr believes the fines are too high. He suggested implementing a $50 fine.