Even in cities that embrace transit-oriented development, too much parking can counteract efforts to create a walkable, attractive downtown. Two recent stories in the Stamford Advocate demonstrate the difficulties involved as the paper’s namesake city works to redevelop the area around its Metro-North station.

Stamford has designated a special “Transportation Center Design District” near the train station, and its zoning board just agreed to reduce the amount of required parking in housing developments in that zone. But requirements are arguably still too high. According to developers, surveys of downtown buildings show that residents of those buildings actually use less than one parking space per unit. But the new regulations require that residential developments provide 1.25 spaces per unit. (The old zoning was even more stringent, mandating at least 1.25 spaces for every studio and one-bedroom unit and at least 1.5 spaces for larger units.)

Still, the zoning board’s decision recognizes that those living near the station (the second-busiest in Metro-North’s system) will require less parking than residents further away. But plans to upgrade the station envision the addition of hundreds of new parking spaces, which will almost certainly increase area traffic. Is that the right move, and is it consistent with the city’s plans to improve transit and cycling connections through the Urban Transitway project?

Stamford is hardly the only city struggling with these issues. In Flushing, Queens, a new development is being planned with more than twice the parking required by the zoning code — 1,600 spaces for 620 residential units and 500,000 square feet of retail and office space — at the insistence of the NYC Economic Development Corporation and some business groups. The project, Flushing Commons, will be blocks from a major subway stop, LIRR station, and over 20 bus routes.

A recently released report from the Institute for Transportation and Development Policy shows that most cities essentially use junk science to develop their parking policies. Parking requirements are often based on what the neighboring town is doing, or on the outdated Institute of Transportation Engineers’ Parking Generation manual, which bases many of its recommendations on suburban land use patterns. Standards based on specific neighborhood context are rare, and even less data informs overall parking strategy. In fact, this week San Francisco became the only major city in the United States to complete a census of all publicly accessible parking.

This lack of rigor is compounded by the political popularity of free parking and often leads to a “more is better” approach. For example, Hartford has quadrupled its downtown parking since the 1960s, according to research by TSTC board member and UConn professor Norman Garrick. But this was hardly an effective strategy if the goal was to keep the city economically competitive. In the same time period, downtown Hartford lost 60% of its residents and the city as a whole lost population and jobs. Three-tenths of downtown Hartford is now devoted to parking, but there are still complaints that it is “not enough.” Parking has pushed out other uses and made parts of downtown unattractive for walking, which creates an incentive to drive instead of taking transit, which creates demand for more parking, which blights more of downtown.

But the ITDP report also shares success stories from cities where smarter management of existing supply, market-based pricing of parking, and zoning changes help support more active downtowns that encourage transit use, walking, and cycling. For example, shared parking for commuters and residents could work for Stamford, since at least some residents’ cars will be gone during the daytime hours when commuters need spaces. Both Stamford and New York could follow the example of Palo Alto, California, which allows developers to pay fees “in lieu” of required parking. Those fees could be used for public investments like widening the crowded Flushing sidewalks, or the unfunded sections of Stamford’s Urban Transitway.