Mobility in New York City is at a tipping point. Average car speeds in the Midtown core have dropped precipitously over the past few years, to a pace barely faster than walking. Streets are crowded with delivery vans, and the number of ride-sharing vehicles has grown disproportionately. The cost of overly congested streets to the city’s economy is estimated to be $20 billion a year.
With the growth of car share, ride share, and bike share, and with driverless cars on the horizon, the number of personal vehicles may wane. But this does not mean that congestion on our streets is decreasing—quite the contrary. In a “tragedy of the commons,” as we find more ways to exploit the space on our streets for vehicles, the urban environment becomes degraded for everyone. Some cities have chosen to manage the use of urban roads with congestion pricing or similar models. A physical redesign would be a bolder, more lasting approach.
The city grid, which once served to organize the development of private real estate by providing access to land parcels, now has a more pressing role to play in making cities livable. Our reimagining of the grid starts from the premise that how we use public rights of way no longer meets the city’s needs, so we should transform the streets radically, dedicating them to pedestrians.
Our idea has two major precedents: the Dutch woonerf and the Barcelona superblock. The shared street or woonerf has a continuous, curbless, textured surface, and through these cues and others (such as signage), nudges car drivers to conform to the speed of pedestrians using the same space—approximately 6 miles per hour.
Variations of the woonerf are being installed in major cities around the world. Amsterdam, for example, has one with bicycle-only access on either side of the street, removing cars from the equation altogether and freeing up the center of the road as a playground.
In Barcelona, the city has been carrying out a radical experiment. It is taking nine-block sections of the city’s grid and making them into “superblocks” that are limited to local traffic inside. The planner behind this concept, Salvador Rueda, found in one early trial (implemented in 2007) that walking and cycling increased, while driving fell considerably, by 26 percent overall.
So, as a thought experiment, we developed a plan from these precedents and overlaid it on Manhattan’s grid. The consistency of the Manhattan grid makes it a good candidate for such a test. Although a similar approach has been discussed for a limited area in Lower Manhattan in the past, we wanted to look at how it could be applied systematically.
We grouped blocks into larger neighborhoods and organized streets into two types: thoroughfares and local streets. Any destination on a local street is within a five-minute walk of a thoroughfare.
Major cross streets, beginning at 14th Street and continuing north (at 23rd, 34th, 42nd, 57th and so forth, until 155th Street), would be converted to thoroughfares, with additional conversions at 18th, 29th, 38th, 47th, and 52nd Streets (just counting those below Central Park).
As a general principle, the selection of thoroughfares prioritizes convenient access to all places in the city while taking into account existing public transportation systems, large housing complexes, and other deeply rooted infrastructures. Thoroughfares would carry most buses and would link to bridges and tunnels that connect Manhattan with the other boroughs and New Jersey. They would not interrupt large parks, housing complexes, or civic and cultural centers that occupy multiple blocks.
Thoroughfares would have one-way vehicle traffic, with the exception of some two-way crosstown bus routes (such as on 23rd Street and 34th Street). With substantially fewer private automobiles and robust investment in public transit, it is feasible that thoroughfares could accommodate all the daily traffic flow around Manhattan.
Local streets, as the name suggests, would only be accessible to local traffic, and would have a speed limit of 6 miles per hour. Congestion on these streets would be eliminated. The low speed limit would reduce the risk of collisions significantly. Pedestrians could occupy the same space as cars with very little chance of conflict. These local streets could be treated quite differently than at present: Traffic lights within each neighborhood could be eliminated altogether, save for the outer edges bordering the thoroughfares.
Within this basic configuration, mini-grids comprising 10 to 15 blocks would function as small neighborhoods of relatively quiet, safe streets, surrounded on four sides by bustling thoroughfares.
The physical design of the thoroughfares would vary slightly from street to street and avenue to avenue. Each proposed conversion would be consistent with the existing street in that it would separate motorized traffic and pedestrian traffic (on sidewalks). However, the dimensions of lanes would be modified substantially.
First, street parking lanes would be removed entirely. When streets are valued as public space, the storage of large vehicles is not the best use of a limited resource. Second, all thoroughfares would have protected bike lanes. On wider streets, the bike lanes would be 10 feet wide, providing space for two-directional traffic; on narrower streets, lanes would be 5 feet wide, designed for one-way traffic.
North-south thoroughfares (such as 5th Avenue) would consist of one bus priority lane and one car lane, each measuring 10 feet across and able to accommodate emergency vehicles. The wider east-west thoroughfares (such as 23rd Street) would have a two-way bus lane and a 10-foot car lane. Narrower east-west thoroughfares (for example, 18th Street) would have a 10-foot car lane and a 10-foot emergency lane.
All the elements combined—dedicated car and bus lanes, bicycle lanes, and pedestrian-friendly spaces—take up less space compared to existing layouts. Avenues would reclaim 24 feet; wider streets, 16 feet; and narrow streets, 8 feet. In the reclaimed space, new amenities could be provided, such as pop-up shops, food and beverage venues, or flexible work spaces. Reclaimed street space could also host charging stations, deliveries, or taxi and ride-share pick-ups and drop-offs.
Local streets would undergo more drastic transformations. They would be curbless; car lanes would be raised a few inches to the level of the original curb, for a level surface (sloped only as needed for drainage). Vehicles and pedestrians would share the space, similar to a woonerf.
Instead of just concrete and asphalt, these streets would feature more varied, textured surface materials. Paving would differentiate the car lanes from the rest of the street, to assist with navigation and prevent inadvertent drifting. Should the need arise, the configuration could be altered temporarily by the use of mechanized navigation devices placed at the ends of each street.
To visualize the potential of this redesign, consider one area of Manhattan, a rectangle bounded by 5th and 8th Avenues on the east and west, 23rd and 18th Streets on the north and south.
This area is mostly zoned for mixed-use, mid-rise commercial and residential uses. It’s dense, with a noticeable lack of public space: no plaza, park, or other green space within its boundaries. Residents would benefit from the additional public space here—particularly flexible outdoor space. Local schools could have outdoor teaching space and use it for community engagement as well.
Streets can become real assets to the city and its inhabitants. In the future, they should function as an extension of the home, the classroom, and the workplace—a realm with new opportunities for recreation and social exchange, many of which we have yet to conceive. We just need the will to make it happen.