Portland planning officials are struggling to find a way to protect the city’s vibrant restaurant scene while also making sure that pedestrians can maneuver through sidewalks and public spaces cluttered with outdoor seating.

“We are not 100 percent sure where the line is right now,” said Jeff Levine, director of Portland’s Planning & Urban Development Department.

City staff met Friday with a small group of restaurant owners to get feedback on some proposed rule changes aimed at finding that balance.

The number of outdoor seating establishments in Portland has more than doubled during the past decade. Last year, 37 establishments located primarily in the Old Port or on Congress Street were permitted to seat patrons outside.

That has led to official complaints from wheelchair users, stroller-pushing parents and other pedestrians about restaurants overextending into the sidewalk space in violation of their permits and city ordinances.

Right now, restaurants must provide 4 feet of space between an outdoor dining area and the sidewalk curb. To make sure restaurants know the boundaries, the city installs 3-inch metal pegs in the sidewalk.

The problem, say advocates for the disabled, is that 4 feet is not enough room when there’s an obstacle in the same area, such as a tree, a bike rack or a public bench.

“It’s a lot to take on,” said Renee Berry-Huffman, a member of the city’s Disability Advisory Committee.

Under a new rule proposed by city planners, restaurants would be required to maintain 5 feet of clearance between seating and an obstacle.

In addition, some restaurant owners have permanently attached their outdoor seating to buildings, and that doesn’t seem appropriate when the seating is supposed to be a temporary use of public space, Levine said. Under the proposed new rules, that practice would be prohibited.

For businesses within a historic district, applications for an outdoor dining permit would also need approval by the city’s historic preservation staff to make sure the seating complies with the design standards in that particular district.

For those restaurants that don’t have enough sidewalk space for outdoor dining, the staff is proposing that business owners have the ability to lease a nearby parking space from the city.

David Turin, owner of David’s Restaurant on Monument Square, who attended Friday’s meeting, said he was pleased with the cooperative attitude of the city’s staff.

“I don’t see a lot of roadblocks being put up there,” he said.

Andrew Volk, owner of the Portland Hunt + Alpine Club on Market Street, who also attended the meeting, said he was glad the city planners reached out to restaurant owners for feedback.

“I feel we were heard and I’m looking forward to seeing what transpires from this,” he said.

Berry-Huffman said a little more room would be a help for people like her. She said outdoor seating can be a real obstacle for her in her power wheelchair, which she has to use because of multiple sclerosis.

“It’s so tight and it’s everywhere,” she said, noting that many restaurants add the outdoor seating on brick sidewalks, which can be hard for people with disabilities to navigate. “You just have to be so careful.”

Levine said the city staff will continue revising the proposals and get input from city councilors before the new rules are implemented.

Staff Writer Edward D. Murphy contributed to this report.