Cities and towns making developers provide too much parking, study says

A study of 200 apartment and condo buildings and complexes largely built in the Boston area since 2000 found nearly 30% of their parking spaces go unused, suggesting planning agencies and boards need to do a better job resisting NIMBY demands for acres of asphalt, the Metropolitan Area Planning Council says.

In the vast majority of developments we studied, the average parking use was less than one space per household, and across the entire sample, only 70 percent of the available spaces were full when surveyed. In affordable housing developments (sites where 50 percent or more of the apartments are deed restricted) demand was even lower: only 0.55 cars were parked per household. ...

At a quarter of the sites, less than half the parking was occupied. The pattern of oversupply was observed in all 14 cities and towns. MAPC counted nearly 6,000 empty parking spaces - over 41 acres of pavement - representing an estimated $94.5 million in construction costs (or about $5,000 per housing unit in the survey).

MAPC numbers show the effect holds even at luxury buildings. At Avalon North Station, which provides an average of less than half a space per unit, 19% of the parking spaces go unused; At AVA Theater District, which provides a bit more than half a parking space per unit, 39% of the spaces go unused. At Gateway Boston, a luxury building in the Fenway, which provides one space per unit, 61% of the spaces go unfilled.

But so what if buildings have some extra parking? Those spaces don't come cheap, the council says:

A more "perfect fit" of parking supply and demand can lower development costs, enable more affordable housing, free up land for open space, and promote sustainable transportation, while also protecting neighborhoods from spillover parking. Communities that adopt a more datadriven approach to decision-making are better able to respond to changing demographics, unique building characteristics, new transportation technologies, and evolving commuting practices.

The council, which represents planners in 40 Boston-area communities, said alleged transit-oriented developments built atop or next to transit stations in particular need to have their parking requirements shrunk:

The more parking is provided, the more likely it is that a household will use it.

These findings make it clear: not only is the overbuilding of parking in residential developments wasting tremendous amounts of money and useful space; but the provision of abundant parking may also be counterproductive to local transportation goals for traffic and sustainability. Transit-proximate developments that provide easy parking are less transit-oriented than they might seem: they’re attracting car-owning households less inclined to use the available transit and more likely to use their cars, affecting local traffic with every trip.