Miami-Dade County’s decision to urgently repair the Bear Cut Bridge joining Virginia Key to Key Biscayne has stirred opposition from people who live on the other side of the bridge, and who say what they really want is a new one.

That would first require a temporary fix to the current one while a new bridge is built. But the county insists that such a short-term mend might not last long enough till the one is finished — putting the only road into and out of Key Biscayne at risk.

Not buying that argument: the Key Biscayne Village Council. At the urging of a vocal resident, the council has asked Miami-Dade to reconsider its repair plan. The county has already put its fix-up project, estimated to cost some $31 million, out to bid; administrators are scheduled to recommend a contractor this month.

The dispute over the future of a deteriorated portion of the bridge has unfolded in pointed memos and tense public meetings. It escalated to the point that Miami-Dade Mayor Carlos Gimenez recently brought a cadre of administrators to Key Biscayne to defend his repair plan — and his character — only to be rebuffed by council members, who said they don’t trust the county.

“My personal integrity has been attacked because, simply, I disagree on a course of action,” an offended Gimenez told the council. “It doesn’t mean there’s anything malicious.... I don’t work that way.”

The council, however, sided with Gene Stearns, a four-decade Key Biscayne resident and chairman of the law firm Stearns Weaver Miller Weissler Alhadeff & Sitterson who has been leading the opposition to rebuilding the beams and roadway on top of the existing bridge foundations.

Stearns told the council to aggressively question Miami-Dade staff.

“Don’t take their word for it,” he said. “They’re up to something. They want our money.”

At the heart of the dispute are two crucial questions: What is the lifespan of the Bear Cut Bridge’s foundations? And is a temporary Bear Cut Bridge fix feasible?

Miami-Dade shut down part of the Bear Cut Bridge in January due to accelerated corrosion of the exposed steel beams that support the roadway. The county has since reconfigured the lanes to allow more auto traffic — but less room for pedestrians and cyclists — in the lead-up to Monday’s opening of the Sony Open tennis tournament in Key Biscayne.

The county put out an expedited bid process last month to repair the westbound portions of the bridge and of the similarly deteriorated West Bridge, located immediately after the Rickenbacker Causeway toll plaza.

Both bridges were built in 1944 and expanded in the early 1980s. Miami-Dade says the newer, eastbound portions of the bridges are structurally sound. The inspections by the Florida Department of Transportation are exempt from public disclosure under state law, to protect national security.

The county wants to remove the westbound roadway to replace the exposed steel beams with ones encased by concrete to prevent corrosion. The existing pilings supporting the structure would remain, though they would be reinforced. New pilings would be added for pedestrian and cycling lanes.

Miami-Dade expects the repairs to extend the bridges’ life by some 40 years.

The problem: The county doesn’t know the lifespan of the 1944 foundations, because there is no documentation providing details of their construction.