What brings together a D.C. neighborhood activist who has never had a driver’s license (much less a car) and a spokesman for AAA? Our shared conviction that proposed changes to D.C.’s zoning regulations will make the city a less attractive place to live, work, play and shop.

The city’s Office of Planning wants to eliminate on-site parking requirements for all new buildings constructed downtown or in mixed-use, transit-accessible neighborhoods throughout the city. But the District’s problem with parking is not that we have a glut of spaces downtown or near Metro stations. In fact, existing parking requirements are already significantly lower than current rates of car ownership and, as a result, they are more likely to produce too few rather than too many parking spaces.

While the Office of Planning contends that the city will grow without adding cars, Department of Motor Vehicles statistics suggest the opposite: The number of vehicles registered in the District increased by nearly 16,000 over the past three years. Curbside parking is already limited and, as the D.C. Department of Transportation acknowledges, will become scarcer as roads are reconfigured to accommodate streetcars and cyclists.

Now is not the time to allow developers to shift parking demand from their projects onto overburdened streets. Existing parking requirements, which encourage the construction of underground garages, have helped to keep downtown pedestrian-friendly. Unlike other cities, our streetscape isn’t continually interrupted by surface lots and parking structures.

Downtown isn’t the only area where parking requirements make a difference. In mixed-use neighborhoods, on-site parking makes it possible for us to share our streets with visitors. Residents frequently ride Metro, bike and walk, but many of us also own cars. And the less we drive, the more we park. Transit-rich neighborhoods are already dealing with parking scarcity as residents, commuters, shoppers, delivery vehicles, service providers and others compete for a limited number of curbside spaces. This situation will worsen if new apartment buildings, stores and offices are built without garages.

Without new parking to go along with new buildings, residents and visitors can ultimately expect to see more restrictions on curbside spaces, as well as higher costs for parking everywhere. Why not simply avoid the problem by retaining the requirement that new buildings include some off-street parking spaces?

It’s clear that current parking requirements are not hampering growth and development in the city. The Office of Planning’s logic is that if parking is scarce and driving difficult, we’ll attract fewer cars. Maybe so. But that also means we’ll attract fewer people. At a time when the District’s downtown and its neighborhoods are increasingly seen as exciting places to be, let’s not seize defeat from the jaws of victory by making parking so time-consuming and expensive that the District becomes a place drivers avoid.

Our planning needs to be realistic. The District’s wealth of transportation options is one key to the city’s appeal. But even as we walk, bike and use mass transit, most of us will continue to use cars because, for some trips, driving remains a necessary option. And our parking policies can’t focus exclusively on city dwellers. In fact, most vehicles here on any given weekday were brought here by nonresidents — commuters, tradespeople and tourists.

There’s a stark choice: Should we use zoning policy to make it difficult for people to drive into the city? Or should we use it to accommodate cars in ways that preserve a walkable urban fabric while minimizing the hassle, congestion and emissions associated with finding parking?

A decision to eliminate on-site parking requirements in the most intensely developed areas of the city would be a major policy change. Such a change should not be left to bureaucrats or an unelected five-member zoning board. We urge Mayor Vincent Gray (D) and the D.C. Council to put the brakes on this attempt to subvert the careful balance struck in the democratically enacted Comprehensive Plan.

Sue Hemberger is a recent participant in the Citizen Planner Initiative organized by the District’s Office of Planning and the D.C. chapter of the American Institute of Architects’. Lon Anderson is managing director of public and government affairs with AAA Mid-Atlantic.