It was an hour and a half into the Zoning Commission’s tenth hearing on American University’s campus plan this fall, and chairman Anthony Hood was asking how the school planned to respond to days of testimony from neighbors, mostly complaining the plan would bring a crush of new cars to their residential streets. Hood leaned onto the dais towards the school’s traffic consultant and said something unusually frank.

“I think you said that traffic impacts will be minimal. That’s what I got out of your presentation, that we won’t even notice it,” Hood told Dan VanPelt, a principal with Gorove/Slade Associates, which handles the lion’s share of traffic engineering for developments in D.C. Anything that needs wholesale zoning changes has to come with a traffic study, which describes how a project might affect pedestrians and cars, and what can be done to mitigate its impact. “I’m going to tell you the truth: I like you, I know you got your job to do, but I don’t believe it…Come on, man. Let’s be realistic. I understand, make it sound good. But let me tell you, this is one commissioner that does not believe it.”

Another commissioner, Michael Turnbull, followed up the good-natured castigation.

“You remember Snow White? Smoke? Mirrors?” he asked. “I think we all think there’s smoke and mirrors involved. You traffic engineers do your job well, but it does get a little confusing. A lot of the things seem to almost be contradictory…If you’re looking at it from a layman’s point of view, it doesn’t make sense.”

VanPelt knew the criticism wasn’t personal—the commissioners’ mistrust ran deeper. “It’s kind of an attack on a profession,” he told Turnbull.

These days, the traffic study is the piece of any zoning discussion that is both most difficult to understand—all those digits!—and easiest to fret over, making it the most politicized document in the application. This is a city, after all, in which citizens picketed to protest anticipated gridlock at Ward Circle if expansions of American University and the Department of Homeland Security went forward as planned. Anyone who’s ever been on a road feels entitled to an opinion, and drivers are particularly sensitive.

“When you in traffic, you guys are the first person I think about,” Hood told VanPelt. “All the book jargon is great, and the studies—this city studies to death. But at the end of the day, it looks to me like transportation’s moving to the point where it pushes all of us onto public transportation. Is that in the manual?”

The short answer: Yes. That helps developers, of course, since it lets them built more without new roads.

And just like land use lawyers and architects, traffic consultants work for developers. That means their job isn’t just to study how buildings will change traffic patterns. They’re also charged with defending projects they work on; as a result, consultants rarely tell communities that new development will cause any problems. The proof: Out of the 17 applications for campus plans and other projects that require big zoning changes filed over the past two years, every single analysis projected that the proposal would have only “slight,” “minimal,” “negligible,” or “no impact” on existing traffic conditions, sometimes provided that minor improvements were made.

Those optimistic projections, though, can help push the District to a less car-dominated future. So maybe we should listen to the traffic experts, anyway.

* * *

Most of the work traffic engineers do to come up with their numbers isn’t that mysterious.

First, they’ll observe the existing conditions, standing outside to count the number of cars, pedestrians, and bikes at every intersection. Then, they’ll take a look at the development proposal, and plug the numbers for the proposed uses—whether it’s a grocery store, dry cleaner, or fitness center—into formulas developed by the Institute of Transportation Engineers to come up with the number of new trips the project is expected to generate.

That’s where the art comes in. Although the formulas are adjusted yearly, a lot of the data is based on suburban developments that don’t have much in the way of transit, pedestrians, or bikes. That gives consultants who do work in cities plenty of leeway to talk about how buses, Metro, bike lanes, Capital Bikeshare, and even future streetcar service will take enough cars off the road to make the impact almost negligible.

But that’s only half the transportation review process. The District has some responsibility, too. Since 2002, when the city’s Department of Transportation became an independent agency, developers have had to meet with staff reviewers long before finalizing their proposal. Before then, consultants would sometimes just write their own reports for the Zoning Commission, since the city was so short-staffed.

Unlike places like Arlington, the regional golden child of transportation management, the District has both height limits and relatively loose zoning restrictions. That means the usual tradeoffs between government and developers—you make the project nicer, we’ll give you an exemption from the code—don’t apply here. All DDOT can do, in most situations, is ask developers to offer more “stuff”: better signals, sidewalk improvements, new bike lanes, less parking, more transit subsidies, anything that will nudge the building’s new occupants to do something other than drive. Consultants will sometimes tell developers this as well, but even transit-savvy builders have to deal with out-of-town tenants and financiers who say the project won’t be worth much unless it has ample room for cars. If developers shrug off DDOT’s advice, there’s not much the agency can do.

“At the end of the day, we are in favor of development,” says Karina Ricks, who headed DDOT’s planning department from 2005 until last year and is now a consultant herself. “If the city stops growing, it starts dying again.”

* * *

No wonder, then, that when neighborhoods think a project will worsen their commutes, they sometimes take matters into their own hands.

For example, worried about the impact of new residential facilities at the University of the District of Columbia—and concerned that a study by Gorove/Slade wasn’t taking into account other studies that had been done over the years—Advisory Neighborhood Commission 3F spent $15,000 to have another firm, Nelson/Nygaard, review UDC’s analysis and make its own recommendations. The outside analysts found a number of flaws, but didn’t have much impact on the final order.

“I don’t think it was worth the cost except to the extent it allowed us to discuss traffic and parking issues with the Zoning Commission,” says ANC 3F chairman Adam Tope. “If we didn’t have this expert, the Zoning Commission would have dismissed all points we brought up to it on traffic and zoning.”

Then there’s McMillan Sand Filtration Plant, where development plans have engendered distrust for decades. A citizen group commissioned an outside expert to review the developer’s traffic study, asking for more information; local ANC officials are sure that adding hundreds more residences and large office buildings will make it impossible for people in surrounding neighborhoods to get to work.

But there are two problems with that.

One: Projects of a certain scale start to develop their own gravity. More residences and office workers are the only thing that justify large transportation investments like streetcars and bus rapid transit. And if there’s a mix of housing, commerce, and offices—which McMillan is supposed to have—people will be able to get to work, buy groceries, and take their kids to a playground without getting in a car. That way, even the largest of new developments won’t have the impact residents fear.

Two: Sometimes traffic is good. Urban places are congested. And well-managed congestion—with a robust array of alternatives—encourages people to do something different, like move closer to where they work, telecommute, or bike instead of drive. All take the pressure off a traffic study as something that people seize on to contain a new development.

Ricks points to the Rosslyn-Ballston corridor through Arlington, which has seen exponential growth over the past few decades and comparatively tiny increases in car trips, due to enlightened planning that placed density close to Metro stations. If regulators had heeded traffic consultants 30 years ago, she says, all those high-rises might never have been built.

“We rely too much on numbers, and we think the numbers are going to give us the secrets to the universe or something,” says Ricks. “What you want to do is change behavior. It’s not about the traffic study.”

Photo by Darrow Montgomery

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