After several crashes and close calls between bicyclists and pedestrians at San Francisco's new Sunset Dunes Park, the city is rolling out changes aimed at improving safety.

Officials plan to add new signs and split the park into two zones.

Last year, San Francisco voters decided to close a stretch of the Great Highway to cars. In April, the city converted that space into a 50-acre surfside park. Since then, officials estimated about 30,000 people visit each week.

Currently, there are few clear signs telling people where they should go, which has led to a mix of cyclists, runners, walkers, and families sharing the same lanes. That lack of separation has resulted in several crashes.

Vanessa Chamberlain said her family visited the park for the first time on Aug. 9. Within five minutes, a man on an e-bike slammed into her 4-year-old daughter, sending the child flying.

"She flew into her knees and then rolled," Chamberlain recalled. "We were very worried about neck injury, head injury. She had a laceration on her head and some road rash on it."

Doctors told Chamberlain that despite cuts and bruises to her daughter's head, arms, and knees, the little girl is lucky and will recover.

"I could have lost my daughter at that moment," Chamberlain said. "That's why I think change for the rules there is just something that's so important.  Because next time, it can be somebody else's child that does lose their life."

The crash is the latest in a series of reported incidents between cyclists and pedestrians since the park opened four months ago.

Starting this week, the city will create two separate zones, adding new signs and pavement markings to make the rules clear. On the west side of the median—the ocean side—there will be a family-friendly area for walking, playing, and kids on non-motorized bikes or scooters. On the east side, the city will allow runners, joggers, skateboarders, rollerbladers, bicycles, and e-scooters.

"The city is listening to people and learning how they want to use the park, and so we should expect this space to continue to evolve as the community has input on what they want to see," said Lucas Lux, president of Friends of Sunset Dunes.

Lux said the park is already safe, but the changes should make it even better.

"I think we need to start with the baseline," he said. "The park is already extremely safe. My kid learned to ride a bike there. It's the only place in my entire neighborhood where I can let my kid off-leash, so to speak, and he can bike a quarter mile ahead of me—and he's barely four.  There's no other space like that in the city."

Some park users said the changes are welcome but may not go far enough.

Susie Leader, who frequently rides her tricycle at Sunset Dunes, said a cyclist recently crashed into her friend. That friend escaped with minor injuries, but Leader still worries about safety.

"If we don't kind of cooperate with each other, we're putting each other at risk," Leader said. "And it's already hard enough with the variety of bikes that we have and speeds that people go, and also young children who are learning to ride, who are unattended or way ahead of their parents."

She believes the new designated zones and signage will help, but only slightly.

"To mix runners and bicycles is not a good idea," she said.

Another park user, Shannon Gordhamer, agreed.

"If you've got e-bikes and you have walkers and runners that are not families, that's too many people in too small of a space," Gordhamer said.

For that reason, Chamberlain said her family won't be coming back anytime soon.

"They would need rules on anything that's motorized. There's no speed limits," she said.

Rec and Park officials said workers will put up temporary signs on light poles and A-frames in the next few days to alert visitors to the changes. Park rangers will also be available to answer questions.

Permanent signs are expected to be installed by the end of September.