What the French gamely call the "art of insertion" is really a multimodal understanding of streets.
Leave it to the French to refer to proper tram design as "the art of insertion."
It will be a long time until Americans are comfortable enough with sexual innuendo to appropriate that term. But there's an awful lot that U.S. cities should learn as soon as possible about the way the French design their transit networks. Whereas American light rail systems have had modest success and modern streetcar lines have questionable transit value, France operates 57 tram lines in 33 cities that together carry some 3 million passengers a day and create a fantastic balance of mobility options for urban and suburban residents alike—all built in the last 30 years.
"We have little streetcars here that carry a thousand people a day. They have lines that carry a hundred thousand people a day," says Gregory Thompson, chair of the light rail committee for the Transportation Research Board and retired urban planning scholar at Florida State. "What's the difference?"
The difference largely comes down to what the French call "insertion," but what Americans would simply see as street design. French cities typically install (insert, if you will) tram tracks onto public right-of-ways—streets, alleys, plazas and the like—even if that means removing car lanes or street-parking spaces to do so. To accommodate trams, streets are often redesigned in full to prioritize pedestrians and cyclists and other potential transit riders. For the most part, trams get exclusive lanes that cars can't use; it's not that the French don't drive, it's that cars don't automatically monopolize city streets.
(It's necessary to pause here a moment and distinguish French trams from American forms of surface rail transit, namely light rail and streetcars. Light rail tends to operate like a train: Loads of passengers board at all doors, tracks run in dedicated lanes, stops are spaced fairly widely apart, and lines often extend well outside a city center. Downtown streetcars tend to share lanes with cars and operate more like a local bus. French trams are close to U.S. light rail systems but do incorporate some streetcar elements in the urban cores.)
In a presentation at the Rail-Volution meeting this September, Thompson and colleagues Tom Larwin and Tom Parkinson outlined five principles that French trams embrace:
- They tie cities together. French tram lines typically extend from urban fringe to urban fringe via the city center.
- They require high-performance transit vehicles. That means large capacities, all-door entry, train-style off-board fare payment, level boarding, and signal priority.
- They have widely spaced stops. Tram stops are spaced far enough apart to improve travel times, but they're placed at critical transfer points with feeder buses or other major lines.
- They reach major destinations. That's a given for good transit, of course, but French tram lines emphasize access to college campuses, office complexes, health centers, and malls, in addition to major suburbs and downtowns.
- They form the core of a larger transit network. Bus lines are reconfigured to serve major tram stops, and fare programs encourage easy transfers from mode to mode.
None of these lessons are especially innovative. But that's the point. The French "art of insertion" isn't some unattainable initiative that American cities can't understand (name aside). Rather, it's more like a blend of America's existing complete streets movement with some core principles of strong surface transit. That's the "main lesson" of the French method, in Thompson's mind.
"You want to figure out where you want to locate lines to serve major destinations, then you want to use the road system to get from here to there," he says. "Streets are a resource. They're a right-of-way that goes from building façade to building façade. You should not think of them as entirely just infrastructure for moving automobiles. There's lots of different claimants on the use of that space, and a major transit line can be one of those claimants. And it can be made not to be some intrusive monster but to function along with the urban fabric."
To be sure, these are differences between French and U.S. cities that complicate the international exchange of tram insertion. The French government is generally more supportive of public transportation; the country's 1996 clean air act, in particular, encourages transit development at the expensive of car travel. The public good often trumps NIMBY interests in France, preventing long battles that end with building costly transit tunnels. (The one new French tram that does run underground, in Rouen, is often seen as a mistake.) Critically, French localities have dedicated transit funding in the form of a payroll tax.
Then again, the French and U.S. patterns of transportation and land use are relatable enough. American metro areas do have lower densities and larger car-ownership rates. But the French still drive and have free parking and live in suburbs and shop at big box stores. The footprints of urban development differ most in degree: Whereas light rail lines in the United States might extend some 20 miles (as in Phoenix), French tram lines only go a fraction as far (Bordeaux's three tram lines run about 5, 9, and 13 miles).
In the mantra of the true scholar, Thompson would like to do more research before he can say for certain how successful the French tram systems have been—particularly in terms of cost. By one recent measure (found here), building a kilometer of new tram in France costs slightly less than in America: An average of $29 million for 11 recent French lines to $35 million for 7 U.S. systems. Meantime French trams return about 50 percent of operating costs through fares, while U.S. light rail returns less than 30 percent. But Thompson withholds any sweeping conclusions until a full cost-benefit analysis is done.
"The French approach seems like something that can be afforded," he says. "Whether it's worthwhile in terms of cost-effectiveness is another question. That's where we'd like to see studies done."
Call it the science of insertion. On second thought, please don't.