A Cotati man driving with what police say was a blood-alcohol level nearly four times the limit at which it is legal to drive in California was among 111 motorists stopped during a special enforcement operation in Petaluma on Friday.

While the bulk of those ticketed — 65 drivers — were cited for excessive speed, suspected drunken driver Christopher Waldron, 48, ended up in jail after he was stopped on Petaluma Boulevard North shortly before 2 p.m. and was found to have a 0.31 percent blood-alcohol level, police said.

Another driver riding a motorcycle was caught without a license or permit and using an illegal helmet, police said. He was speeding, too, they said.

In total, 111 traffic stops were made and 96 citations issued over the course of the 10-hour enforcement operation. Two drivers had suspended licenses and two had no license, police said.

But speed was the main focus of the special operation because it is the No. 1 cause of collisions in the city, Sgt. Ken Savano said.

The operation was funded by a grant from the California Office of Traffic Safety, through the National Highway Traffic Safety Administration, Savano said.