Wooden benches appearing at bus stops across Bay Area. Who is behind them?

SAN FRANCISCO (KGO) -- The benches are appearing throughout the Bay Area. This map shows close to 90 spots in the East Bay and eight in San Francisco. The benches are screwed right into the concrete on city streets.

Luz Pena: "What do you think about the bench?"

"I love the bench. I was so excited when I saw it and then I looked up this thing, and it was so fun to hear that it was a group of people who are basically doing it on their own because we need them," said Ed Kinchley, San Francisco resident.

"I like it. I like it better than the old one because glass get broken all the time on those," said Michael Corey, a San Francisco resident.

Who are the people behind them? And is this legal? The only clue is this website on the benches leading us to the San Francisco Bench Collective.

We went to the East Bay where one of the first benches was installed about two years ago and met Carter Lavin. He is in contact with the mysterious group behind the benches.

"My group, the Transbay Coalition is working with cities, is working with this benching group to get this effort more fully legalized because right now it's operating in a legal gray area," said Carter Lavin, co-founder of the transportation advocacy group Transbay Coalition.

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We confirmed the SF Bench Collective focuses on bus stops and everyone making them are volunteers.

"There are a lot of very high traffic bus stops that don't have benches and the group prioritizes those. Especially those where a bench could be there. Like this spot right here - there is plenty of space, it is ADA compliant to do that. The group prioritizes that. They also have a request form on the San Francisco Bay Area Bench Collective website. Where people say, 'Hey I'll like a bench' - I believe preference will be given to people who say I will maintain it and take care of it," said Lavin.

San Francisco got the first benches on June 8. The city is not too excited about these benches. In a statement, SF Public works said in part:

"We are aware that benches have been installed without permits. While the benches are intended as a public convenience, we have the legal responsibility to ensure access and public safety. We also have concerns about maintenance and liability."

Despite this, this group is moving forward.

"Plans to expand to other counties and region as well as just continued to double down because it's one of those fun things where people see this and they get in touch with the group and say, hey how can I help I love my city, I love my fellow transit riders, I love woodworking, or I'll like to learn how, how do I get involved?," said Lavin.

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The materials to make these benches comes out to about $100 according to Lavin. In several cases, cities have removed some of the benches.

SF Public Work's full statement:

"We are aware that benches have been installed without permits. While the benches are intended as a public convenience, we have the legal responsibility to ensure access and public safety. We also have concerns about maintenance and liability. We already saw that at least one bench has been tagged by graffiti vandals. Will the people who installed the benches remove the tags? We of course are wiling to work with the bench sponsors on a path forward."

SFMTA full statement:

"We want our riders to be comfortable-on Muni and while they're waiting for their line. Our goal is to install transit shelters at stops where we have boardings of 125+ per day.

While we appreciate the sentiment behind these bench installations, there are a lot of complex issues that would need to be addressed. If a bench is tagged with graffiti, it raises the question of who is responsible for upkeep. More importantly, if someone is injured while using one, the issue of liability becomes a serious concern. We also need to be mindful of accessibility and making sure that someone in a wheelchair can still get by on the sidewalk."