Designing better intersections

New Yorkers (and, I suspect, others in large cities) rarely wait for a 'Walk' light - they cross when it is safe to do so. They step into the street checking for traffic. There is this area in the street that is not used by vehicles driving or parking that people penetrate into. I explored how this space could be built to provide a safer area for pedestrians to wait before crossing the street. That evolved into using these larger peninsulas for signposts, bollards on the corners for protection, and enhanced bus wait lines.

Advantages of the improved intersections
1. Safer movement of vehicles and pedestrians.
2. More aesthetic.
3. Better placement of service modules - trash, info, signs.
4. More efficient and complete communication of information.

Pedestrian peninsulas

Normal intersection with one-way streets, bus lane, parked cars, and pedestrian crosswalks. Traffic pattern shows the light-colored space that is free of vehicles.

Proposal with pedestrian peninsulas that help control traffic and people. Version with parking along one side of the primary street.

Examples of street space not used by vehicles that could benefit from pedestrian peninsulas.

Example of present squared corner with bollards defining the sidewalk. Diagrams showing the peninsula concept, here called a 'neckdown' and a 'bus bulb', as devices used by highway engineers for traffic calming.

Examples of of curb neckdowns

Better left turn guides
New York combed through more than 1,000 traffic-crash reports to better understand the dangers surrounding left turns. It found that left-turning vehicles caused 3 times as many pedestrian and biker casualties as right-turning vehicles. The city’s DOT found that left turns are dangerous for three reasons:
1. A car’s frame blinds its driver during a left turn, much more than during a right - poor visibility makes crashes more likely.
2. Drivers drive faster in left turns because they have a wider radius than with right turns - speed makes crashes more fatal.
3. Drivers cut corners during their turns - expanding the area where pedestrians can get hit - making a crash more likely.

NYC DOT created a different intersection design to target these issues. The Hardened Centerline slows down drivers and discourages them from cutting corners and the Slow Turn Wedge uses markings and flexible plastic posts to buffer pedestrians from traffic and shrink the area where they could get hit by a car.

Protected Intersection design concept

This proposed intersection is a great idea - an intersection with segregated lanes for vehicles, bikes, and pedestrians.

Website for the Protected Intersection design concept. More details in this video.
Below: A similar solution being used in Holland.

Bus queue lines

Close-up of one corner showing placement of signposts and bus queue rails. The dark line in the bus line represents a metal railing to protect the waiting passengers. The white parallel line is engraved in the sidewalk. It provides guidance on how to form the line without narrowing the sidewalk when there is no line waiting. Similar to these queue lines at Chase bank:

Samples of bus platforms along Broadway in NYC.

Improved crosswalk stripes
Striping the crosswalks parallel to pedestrian path keeps the users aligned, making it easier to get bearings in the crowd, to know direction, and to pass oncoming pedestrian traffic. Perpendicular to vehicle traffic makes them more obvious, as a barrier to cross - conveying caution, be alert. Three lines - two outer boundary lines and a center stripe - suggest a two-way lane, as we are accustomed to in roadways.

Stripes parallel to traffic flow make a more cumbersome walkway and are not oriented to help pedestrians.


Sketch of a new signpost with, from top to bottom, light identity globe, street names, map and info of area sights, trash can with ads on 4 sides. Sample of existing info signpost on Broadway by Trinity Church.

Inspiration: May/June 2007
Sketches: June 2007
September 2007: New York City announced plans to install 'pedestrian refuges' along Ninth Avenue. These raised islands would make it easier to travel across intersections by shortening the distance required to cross the street.