Walczak on Morrissey Boulevard: Mayoral candidate Bill Walczak used a red yardstick as he discussed his concerns about the regular tidal flooding that he says is worsening on Morrissey Boulevard. Photo by Gintautas Dumcius

Bill Walczak is a self-described “map freak.”

There are maps of Dorchester, Boston and New England all over the walls of his home up on Savin Hill. The maps show a Boston before parts were filled in to make new neighborhoods and new roads, before climate change entered the broader public conversation.

“The reality is that those maps show a period of time before they filled in the land,” Walczak said on Thursday, standing on Malibu Beach as cars on their way to Boston rushed by. “So in fact Morrissey Boulevard filled up here. This is all fill land. But we also have this problem where the sea level is rising and you can see it on Morrissey Boulevard.”

Walczak said he can see it because every time they close down Morrissey Boulevard due to the high tides – almost a monthly occurrence – since commuters drive through his neighborhood instead. “That’s a major change from what happened even ten years ago,” he said, saying flooding was once a rare thing. “We didn’t see this stuff ten years ago and I don’t think Morrissey Boulevard actually sunk. I think what’s happened is the sea level has actually risen and we’re getting storm surges that are very, very damaging and tidal surges that are damaging.”

As the rain moved in, a small group of supporters of Walczak’s run for mayor made its way from the beach to a cracked and jagged sidewalk and waved signs at the oncoming traffic. Walczak, carrying a neon pink yardstick, walked down the beach and stopped to film a campaign video touting his plan to combat climate change.

If Hurricane Sandy, which caused $68 billion in damages nine months ago, mostly to metropolitan New York, had reached Boston earlier, City Hall would have been flooded as well as coastal areas of Dorchester and South Boston, Walczak said.

And while Mayor Thomas Menino has come up with an action plan, Walczak, who once served as associate commissioner of the Boston Department of Parks, said he wants to go further. He wants a renewable energy requirement for city buildings set at 30 percent by 2020 and a public transportation system that runs 24 hours a day, 7 days a week, among other ideas in an “environmental blueprint” he unveiled on Malibu Beach. Walczak also called for expansion of the Silver Line to Mattapan Square and East Boston.

“Boston has the capacity to do this,” Walczak said. “This is one thing I keep emphasizing in my campaign: If there’s one city in America that should be able to solve its problems, it’s Boston. We have the resources here. We have the intelligence, the universities, the colleges, the research institutions that are capable of designing a plan to make Boston safer, to make Boston greener, to make Boston healthier, to deal with the achievement gap in education. If there’s one city in American should be able to do it, it’s us, and what it needs is strong leadership, and that’s what I’m willing to provide.”