Hundreds gathered Saturday morning on the banks of the American River in Rancho Cordova for “Raftopia,” a nonpermitted event that prompted a one-day alcohol ban.

Sgt. A.J. Bennett, a Sacramento County Regional Parks ranger, said the Rancho Cordova Police Department, Sacramento County Sheriff’s Department, volunteer mounted officers and California Department of Fish and Wildlife personnel assisted rangers Saturday to ensure participants had a safe day on the river.

“The water will wear a swimmer out in a hurry,” Bennett said.

Park ranger Greg Stelzner said the Saturday crowd was mellow.

“We have a good crowd. … A couple of church groups came through,” Stelzner said. Rafters were cooperative, either throwing beer away or taking it back to their parked vehicles.