Political leaders are barking up the wrong tree as they try to compensate for the negative impacts of development in Boston.

Southie’s own Rep. Stephen Lynch late last year tried to extort a 120-spot parking garage for the project’s neighbors from Redgate Capital and Hilco Development Partners in exchange for his acquiescence to the companies’ redevelopment of the toxic, decrepit South Boston Edison site. Now, as Scott Van Voorhis notes in his column this week, two Boston city councilors are proposing substantial fees on so-called “flippers.”

It’s a simple case of geometry: Greater Boston must find ways to increase density in areas near jobs and mass transit to accommodate the economic and population growth happening around their ears. Unless we want our region to continue choking on traffic, this growth must be accommodated in places where increased numbers of people can be moved efficiently.

South Boston is a textbook case of how not to handle the impact of development and density. The neighborhood has for years been one of Boston’s biggest boomtowns, but beyond the problematic Silver Line precious little has been invested in moving all those new residents and workers around in an efficient manner.

Instead of demanding less density from developers – or worse, more parking – more communities should follow the example of towns like Arlington. There, planners and community leaders ask developers of multifamily units to proactively manage the transportation demands created by their projects by leaning on the town’s bicycle infrastructure and MBTA bus routes.

Arlington also offers a possible way forward on the Edison project. Instead of demanding a smaller project or an expensive parking garage which will only encourage more car ownership in the neighborhood, as plenty of research has shown, city leaders should ask for help building dedicated bus lanes on traffic-clogged Broadway and Summer Street between the City Point bus terminal next door and Red Line stations.

As Arlington recently found with a pilot, rush-hour-only bus lane on Massachusetts Avenue, a few gallons of paint and a few hours of police enforcement dramatically sped up bus trips and pulled not-insignificant numbers of drivers out of their cars and onto the bus.

So long as local governments are intent on squeezing developers for significant investments to mitigate their projects’ impacts, they should at least make sure their demands are productive.