Boston's City Council voted unanimously on Wednesday in favor of an ordinance that would ban the use of flimsy plastic bags at checkout counters and would require businesses to charge a nickel each for sturdier plastic bags and for paper bags with handles. 
 
Specifically, the ordinance bans all plastic bags thinner than 3 mils, or 3 thousandths of an inch. 
 
The ordinance has been kicking around Council for more than a year, while Council members listened to public comment, met with industry representatives, and assembled support from environmental groups, neighborhood associations and even Girl Scouts. 
 
And casting a shadow over the effort has been Boston Mayor Marty Walsh, who has said in the past that he was opposed to the measure and, while he did say this week that he was "open" to it, has declined to say whether he'll sign the ordinance even after Wednesday's unanimous vote. 
 
Were Walsh to veto the measure, the Council could override with a two-thirds majority.
 
Cities around the state and around the country have passed similar measures, including Cambridge, Brookline, Somerville and Watertown.  
 
Speaking before the vote, City Councilor Matt O'Malley, the ordinance's lead sponsor, said the time had come to pass the ban in Boston, citing both the large-scale environmental impacts of plastic (including the alarming rise of plastic found in the bodies of fish and other wildlife) -- and local impacts. 
 
"They end up in our streets, in our storm gutters, in our trees, tangled, in our wildlife and in our marine ecosystem," O'Malley said. 
 
"I would argue that as it stands we are currently paying a fee for these plastic bags," he added, noting that the city's recycling contractor has said that it is tasked with trying to remove some twenty tons of plastic bags from the city recycling stream every week. 
 
"Our department of Public Works, Water and Sewer, Parks, and other city employees spend time cleaning up these bags from trees, from parks, from lots, from storm drains, from waterways."
 
Council President Michelle Wu, a co-sponsor and strong supporter of the ban, called it a"small change that will have a major impact." She described the vote as a meaningful step in the Council's larger effort to step up to the challenges the city will face from global climate change. 
 
"It's about taking that affirmative step and joining every other community that has made the statement that 'We are going to take responsibility for climate justice; We're going to take responsibility for our role in protecting and ensuring a livable future for generations to come."
 
Reaction from opponents and supporters was swift. Shortly after the vote, the American Progressive Bag Alliance, which lobbies on behalf of plastic bag manufacturers and related plastic industry interests, released a statement saying it was a "a shame that City Councilors pushed through a tax that will hit seniors and low-income families the hardest in the middle of the holiday shopping season," -- though the ordinance does not take full effect until next year. 
 
The Massachusetts-based Conservation Law Foundation, in its own statement, praised the ordinance while shifting attention to the noticeable silence on the matter that has come from the Mayor's Office in recent days.
 
"We are optimistic that Mayor Walsh will follow the lead of 59 other Massachusetts cities and towns," the statement noted, "and sign this ordinance into law.”
 
A spokesperson for Walsh said the mayor was "still reviewing" the bill.