Due to fears of terrorism, participants in next year’s San Francisco Marathon may have to stick to the sidewalk when crossing the Golden Gate Bridge.

The Golden Gate Bridge District Board of Directors followed the recommendation of staff Friday and voted 10-4 to adopt a resolution reaffirming that bridge roadways are unavailable for special events and “expressive activities.”

“In light of recent world events we are no longer comfortable not having a physical barrier,” said Denis Mulligan, bridge general manager. “The board made the decision that the roadway is for cars, and special events can be on the sidewalks. Most of them are anyway.”

In a typical year, about 44 special events occur on the bridge.

Sam Singer, a spokesman for the San Francisco Marathon, said, “We’re disappointed at the bridge district’s decision today but we’re not giving up. We’re hoping to go back to the board and staff to see if we can change this outcome.”

The district already had an ordinance establishing this policy; however, over the past 14 years it has granted exemptions to such events as the San Francisco Marathon and the US Half Marathon.

During those foot races, the district closed lanes as necessary to ensure that there was a buffer lane open between runners and northbound traffic.

Due to a number of recent incidents worldwide in which terrorists used vehicles as deadly weapons, the bridge board took special precautions during the San Francisco Marathon in July. The district closed the bridge to all northbound traffic other than emergency responders, buses and escort vehicles for three hours. The traffic closure made it possible for a physical barrier to be present between the event participants and traffic on the bridge.

“To close the bridge is not fair to the drivers who use it and the buses and transit,” said Supervisor Judy Arnold, a bridge district board member who voted with the majority.

Mulligan said, “We only did that as a one-time exception because it was too late to replan or cancel the event. A couple of weeks prior to that there were a couple of horrific instances where people took vans and drove them into crowds of people.”

Between March 2006 and August 2017, there were at least 10 separate terrorist attacks involving vehicles. These included the 2006 attack in Nice, France, in which at least 84 people were killed and the 2017 attack in Barcelona, Spain, in which 13 people were killed and 100 people injured.

Singer said, “We believe that safety is paramount in every instance.”

He added, however, that instead of preventing terrorism the bridge district’s action “winds up bowing to terrorism.”

“Take Boston for example, the site of a terrible attack on the Boston Marathon,” Singer said. “Boston didn’t give up after that terrible incident. It became stronger.”

Asked if San Francisco Marathon runners could use the bridge’s sidewalks, Singer said, “It’s very difficult to just stick to the sidewalk given the large number of people who run this race. I’m not sure that is possible. But we’re going to look at it and work with the bridge district to see what opportunities are there.”

Singer also said, “We’ve been in discussion with the bridge district about some sort of movable barrier that would prevent terrorist attackers from weaving into the lanes being used by the runners. We hope to continue to explore that opportunity with the bridge district.”