The wide and graceful figure-eight road that encircles San Francisco’s Twin Peaks is about to be cleaved into a pair of threes, a move to improve safety that comes two months after the city settled a lawsuit over a fatal crash at the scenic overlook.

The plan — a two-year experiment designed to make more room for tourists, hikers, runners and bike riders — was approved by the Municipal Transportation Agency board this week, but not before it ran up against a barrage of opposition.

Nobody lives along this stretch of road, but frequent visitors feel an intimate attachment to the undeveloped ridgeline with the famously spectacular view.

Starting this summer, the MTA will break out the paint, signposts and traffic barriers and transform the one-way figure-eight stretch of Twin Peaks Boulevard. The half of the roadway offering panoramic views of downtown, the bay and beyond will be reserved for bicyclists and pedestrians. The ocean-view side will carry auto traffic, including lots of tour buses, in both directions.

The MTA and the Recreation and Parks Department devised the plan as a way to make Twin Peaks safer and more parklike by providing more room for walkers, protected space for bicyclists and easier connections between trails for hikers and runners trekking up the peaks and down the hillsides.

The road is not rated among the city’s most dangerous. But in December 2012, Yuee Yao, a 56-year-old woman visiting her son in San Francisco from China, was killed by a drunken driver as she walked up the hill. Two other visitors in the group attempted to scramble over a 2-foot concrete barrier and out of the way, but they were also injured by the swerving driver.

The city settled a pair of lawsuits in January for $700,000, said James Hannawalt, deputy city attorney. The MTA, which will pay half the settlement, approved payment in February. The rest, to be paid by the Recreation and Parks Department, still needs approval by the Board of Supervisors.

The 23-year-old motorist, Gina Eunice, was convicted of manslaughter and drunken driving and sentenced to four years in prison.

Lawsuits barely discussed

As part of the lawsuits, attorneys argued that the city had long been aware of the dangers of the figure eight. But the fatal collision was barely mentioned at the MTA’s meeting Tuesday as the Twin Peaks plan was being debated. Agency officials and Hannawalt said the changes were not part of the settlement or motivated by the lawsuit.

“The project was well in the works well before that unfortunate tragedy,” said Ben Jose, an MTA spokesman. “But it underscores the importance of having dedicated places for people walking, biking and driving at Twin Peaks.”

Cameron Beck, a traffic engineer, told the MTA board that the plan was designed to protect pedestrians and bicyclists by separating them from drivers.

“This provides our most vulnerable users with a dedicated space completely safe from motor vehicle traffic,” he said.

Objections from some

But some Twin Peaks regulars, including hikers and bike riders, objected to the changes, saying the plan would expose walkers and cyclists who want to see the ocean-view side to more danger.

Ilya Kaltman, who has hiked the area regularly over the past 15 years, called the program “a solution asking for a problem” and said it would deprive many visitors of full access to Twin Peaks, which is a city park.

“As it is now, hikers, cars and bicyclists are able to access every inch of that figure eight, which is the beauty of Twin Peaks,” she said. “To take that away is a loss — an extreme loss.”

Others, including representatives of bicycling and hiking advocacy groups, praised the plan, saying it would not only improve safety but open a wider expanse of Twin Peaks to visitors who might be too timid to stroll alongside moving cars and buses.

“This will make Twin Peaks a benefit for everyone,” said Julia Raskin, an organizer with the San Francisco Bicycle Coalition.

Impact on tours, filming

Representatives of the tour bus and film industry expressed concerns about the plan restricting their access to the popular vista point. Susannah Robbins, executive director of the San Francisco Film Commission, said the figure-eight road is much sought-after by filmmakers and television and commercial producers.

“Its scenic curves and winding and undeveloped roads reveal the majestic views of our city below,” she said. “It personifies San Francisco.”

Limiting access to those views, she said, could cost the city jobs, revenue and recognition. Tour guides also worried that the changes could cause traffic backups and force them to exclude Twin Peaks from tightly scheduled bus tours, which are already forced to forgo some tourist hotspots.

“We can’t go to Lombard Street. We can’t go to Alamo Square,” said guide and bus driver Phil Siegel. “People always ask for Twin Peaks.”

Most in favor

On a sunny Wednesday this week, visitors enjoyed the place, taking a noontime walk along the sidewalk-less road — and sometimes in lanes of traffic — on their way to Eureka and Noe peaks and to the nearby Christmas Tree Point observation area.

Atop Twin Peaks at noon, tourists and locals alike enjoyed the lunch-hour views, sunshine and light breezes. Most favored the idea of turning the west half of the figure eight into a car-free, bus-free zone.

Software engineers Ruthie Bendor, 30, and Pete Emerson, 41, sat on the barrier at the side of the road, eating their lunch and chewing on the idea of a motor-vehicle-free zone.

Bandor, who often pedals a bike to Twin Peaks, liked the idea of the bike and pedestrian area but feared that crossing through traffic to get there could be dangerous. She also worried about the potential for head-on collisions on the two-way road.

“I don’t really see it as a big win one way or the other,” she said. “I guess we’ll have to try it out and see.”

Michael Cabanatuan is a San Francisco Chronicle staff writer. Email: mcabanatuan@sfchronicle.com Twitter: @ctuan