Boston officials Wednesday night sought approval by Quincy’s Conservation Commission of plans to invest $92 million to rehab the Long Island Bridge, but the commission punted on the decision pending further consideration.

Quincy City Councilor William Harris, who represents the Squantum area where the Long Island bridge would connect with Quincy streets, was among more than a dozen people to denounce the plan in a nearly three-hour meeting — one of the first chances Quincy leaders got to square off against Boston in public.

Harris says Boston should scrap the bridge plans altogether.

“Boston continues to undertake this project without explaining why it will not invest in the less expensive, more environmentally friendly alternative of ferry service,” Harris said, echoing the position of Quincy's mayor.

Speakers raised a multitude of concerns over the plan to rehab the Long Island Bridge, ranging from the presence of lead in the water to the structural viability of the existing support structures to the impact on marine life.

“Our engineers have raised a number of serious concerns,” Harris added, “all of which go away if Boston simply will tap the existing ferry capabilities which can easily be expanded to serve Long Island.”

Though Long Island belongs to Boston, the other side of the bridge starts in Quincy, and approval is required from municipal boards on both sides. The project received swift approval from Boston’s conservation board in May.

After Boston’s Conservation Commission vote, Quincy’s City Council voted unanimously to bar construction vehicles from the bridge site in the Squantum section of the city. It’s unclear how that could affect the bridge work, though much of the city’s plans involve floating materials to the site by boat.

Boston’s Chief of Streets Chris Osgood led the city’s contingent at the meeting, backed by the engineering consultant and the environmental consultant heading the project.

“On Jan. 1 of this year, as you know, Mayor [Marty] Walsh made an announcement that we plan on reactivating the recovery campus on Long Island as a way of expanding the region’s continuum of care and addressing the opioid crisis that were all facing,” Osgood told the commissioners. “Part of the reopening of the recovery campus is the reconstruction of the Long Island Bridge.”

The city budget set aside $80 million toward the bridge work, doubling down on one of Walsh's promises upon beginning his second term as mayor.

Among Quincy residents, only two supporters of the plan spoke at the meeting, saying Quincy should cooperate with Boston on the plan.

Quincy resident John Rodophele said he supports the bridge project because it’s going to help in the fight against opioid addiction.

“Maybe we should work with the city of Boston — if we weren’t fighting them like we’re doing right now — and maybe they could dedicate 25 percent of those beds to Quincy residents so we don’t have heroin addicts sprawled all around the streets," Rodophele said. "As soon as a Quincy police officer finds one, they can take them right to Long Island.”

The Conservation Commission agreed to continue the hearing until its August meeting. Should Boston or Quincy disagree with a ruling, it could be appealed to the state Department of Environmental Protection.

John Shea, who was hired as special environmental council to the city of Quincy to take on Boston's bridge plans, says the legal battle could last years.

After the meeting, Shea told WBUR the city wants “full disclosure of how the thing is going to be constructed and whether they have adequately estimated what the wetland impacts are.”

Boston's plans to fix the bridge are slated to begin next year and to be finished by 2021. But not if Quincy has any say in it.