“When we plan for walkability, we need to factor in behavior”: the case for continuous pavements

Little Green Street, Kentish Town, north London. Image: Getty.

An extract from a new book, Soft City: Building Density for Everyday Life.

Jan Gehl frequently reminds us that human beings are biologically designed to walk. Walkability is about accommodating walking, making it easy, efficient, and enjoyable.

Walking will always be a vital component of urban life. It is the most essential and basic form of mobility. Every journey, regardless of the mode of transport, begins and ends with walking. You walk to the carpark or the bicycle shed; you walk to the bus stop; you walk to the metro platform. Walking is what makes all of the connections to the city possible, what connects us to the places in closest proximity, and what has the potential to get us beyond our immediate surroundings.

The pace of walking allows for a rich, sensory experience, promoting social interaction as well as connections to the surrounding environment. Urban spaces can be designed to enhance these experiences, improving overall walkability. This means creating comfortable, attractive, and continuous walking surfaces, and spaces that make it safe, easy, and intuitive for diverse groups of pedestrians to move among the other forms of traffic sharing the same spaces.

Unlike other forms of transport, people can have total control when walking— spontaneously stopping and going at will. Walking is the form of transport that is most responsive to what is going on around us and offers the most opportunities for connection. The short walks to connect to other modes of transport are particularly important.

If you drive straight into an underground garage from the street and then take a lift up to your home or office, you are denied the opportunity to connect with place, people, and planet. Simply separating the place for storing cars from the home or workplace with a small walk, apart from having some obvious health benefits, opens up the possibility of connecting. It offers a chance to see what is happening on your street, to see other people, and to feel the weather on your skin.

Different kinds of people walk in different ways, with different stuff. Designing for walkability must take into account the diversity of people walking and their circumstances. Some are in a rush to get their bus, where every second counts.

Others are strolling and looking for excuses to stop. Some people are actively engaging in exercise while others, like the postal carrier, are at work. Some will be wearing sensible walking shoes, while others will be in high heels or rubber boots. These different people with their different needs and different paces share the same sidewalk.


In the same way, there is also a range of urban equipment that people may have with them, allowing them to do more and be more comfortable as they move about the urban environment. The prams and strollers, shopping trolleys, walking frames, wheeled suitcases, tote bags and shopping baskets, rucksacks, folding bicycles, headphones, mobile devices, water bottles, coffee cups, umbrellas and parasols all influence the way pedestrians move and use space. When we plan for walkability, we need to factor in this equipment and the accompanying behavior, and understand how it might help or hinder how people move and the space that they need.

In the hierarchy of urban streets, it makes sense to let the vehicle traffic flow uninterrupted along more-important streets, and have traffic stop and yield on more-minor or side streets. The same should be true for pedestrian traffic. Why should pedestrians on a main thoroughfare have to stop and wait at every single side street when the vehicles travelling in the same direction don’t have to? Pedestrian crossings sometimes force those walking to make detours, throwing them off their natural direction or desire line, to allow for a road geometry based on the turning circle of large vehicles. Pedestrians often far outnumber vehicles in an urban setting. Who should be prioritised when designing the street?

In Copenhagen and other cities, walking is prioritized by designing the sidewalk as a continuous surface, to stretch over side streets. This effectively transforms several smaller blocks of sidewalk into a single, long block. Turning cars have to carefully negotiate their way across the sidewalk, observing and respecting the pedestrians, and always yielding to them.

Redesigned side-street crossings that prioritise the pedestrian alter the balance of who has the right-of-way in traffic. People on foot are favored because motorists come as guests in the pedestrian realm. The crossings are a simple change, but make a huge difference for pedestrians in terms of level of access, comfort, and safety on the sidewalk.

The continuous sidewalk can eliminate frequent and annoying changes in level, which makes things easier for people using wheelchairs, prams, and strollers, wheeled luggage and shopping trolleys, scooters, and kick bikes. Overall, the continuous sidewalk creates a more comfortable, safe, and pleasurable experience for people walking. It is also faster since there is no time wasted waiting for traffic at side streets. The continuous sidewalk means that children can be more independent, exponentially expanding their everyday networks – walking to school, visiting friends, and performing errands are possible without adult supervision. Having this safer mobility option can open up a whole new world of freedom, learning, and experience for a child, and can give free time back to their parents.

Architect David Sim is partner and creative director at Gehl. Soft City is out now from Island Press.

 
 
 
 

To build its emerging “megaregions”, the USA should turn to trains

Under construction: high speed rail in California. Image: Getty.

An extract from “Designing the Megaregion: Meeting Urban Challenges at a New Scale”, out now from Island Press.

A regional transportation system does not become balanced until all its parts are operating effectively. Highways, arterial streets, and local streets are essential, and every megaregion has them, although there is often a big backlog of needed repairs, especially for bridges. Airports for long-distance travel are also recognized as essential, and there are major airports in all the evolving megaregions. Both highways and airports are overloaded at peak periods in the megaregions because of gaps in the rest of the transportation system. Predictions for 2040, when the megaregions will be far more developed than they are today, show that there will be much worse traffic congestion and more airport delays.

What is needed to create a better balance? Passenger rail service that is fast enough to be competitive with driving and with some short airplane trips, commuter rail to major employment centers to take some travelers off highways, and improved local transit systems, especially those that make use of exclusive transit rights-of-way, again to reduce the number of cars on highways and arterial roads. Bicycle paths, sidewalks, and pedestrian paths are also important for reducing car trips in neighborhoods and business centers.

Implementing “fast enough” passenger rail

Long-distance Amtrak trains and commuter rail on conventional, unelectrified tracks are powered by diesel locomotives that can attain a maximum permitted speed of 79 miles per hour, which works out to average operating speeds of 30 to 50 miles per hour. At these speeds, trains are not competitive with driving or even short airline flights.

Trains that can attain 110 miles per hour and can operate at average speeds of 70 miles per hour are fast enough to help balance transportation in megaregions. A trip that takes two to three hours by rail can be competitive with a one-hour flight because of the need to allow an hour and a half or more to get to the boarding area through security, plus the time needed to pick up checked baggage. A two-to-three-hour train trip can be competitive with driving when the distance between destinations is more than two hundred miles – particularly for business travelers who want to sit and work on the train. Of course, the trains also have to be frequent enough, and the traveler’s destination needs to be easily reachable from a train station.

An important factor in reaching higher railway speeds is the recent federal law requiring all trains to have a positive train control safety system, where automated devices manage train separation to avoid collisions, as well as to prevent excessive speeds and deal with track repairs and other temporary situations. What are called high-speed trains in the United States, averaging 70 miles per hour, need gate controls at grade crossings, upgraded tracks, and trains with tilt technology – as on the Acela trains – to permit faster speeds around curves. The Virgin Trains in Florida have diesel-electric locomotives with an electrical generator on board that drives the train but is powered by a diesel engine. 

The faster the train needs to operate, the larger, and heavier, these diesel-electric locomotives have to be, setting an effective speed limit on this technology. The faster speeds possible on the portion of Amtrak’s Acela service north of New Haven, Connecticut, came after the entire line was electrified, as engines that get their power from lines along the track can be smaller and much lighter, and thus go faster. Catenary or third-rail electric trains, like Amtrak’s Acela, can attain speeds of 150 miles per hour, but only a few portions of the tracks now permit this, and average operating speeds are much lower.

Possible alternatives to fast enough trains

True electric high-speed rail can attain maximum operating speeds of 150 to 220 miles per hour, with average operating speeds from 120 to 200 miles per hour. These trains need their own grade-separated track structure, which means new alignments, which are expensive to build. In some places the property-acquisition problem may make a new alignment impossible, unless tunnels are used. True high speeds may be attained by the proposed Texas Central train from Dallas to Houston, and on some portions of the California High-Speed Rail line, should it ever be completed. All of the California line is to be electrified, but some sections will be conventional tracks so that average operating speeds will be lower.


Maglev technology is sometimes mentioned as the ultimate solution to attaining high-speed rail travel. A maglev train travels just above a guideway using magnetic levitation and is propelled by electromagnetic energy. There is an operating maglev train connecting the center of Shanghai to its Pudong International Airport. It can reach a top speed of 267 miles per hour, although its average speed is much lower, as the distance is short and most of the trip is spent getting up to speed or decelerating. The Chinese government has not, so far, used this technology in any other application while building a national system of long-distance, high-speed electric trains. However, there has been a recent announcement of a proposed Chinese maglev train that can attain speeds of 375 miles per hour.

The Hyperloop is a proposed technology that would, in theory, permit passenger trains to travel through large tubes from which all air has been evacuated, and would be even faster than today’s highest-speed trains. Elon Musk has formed a company to develop this virtually frictionless mode of travel, which would have speeds to make it competitive with medium- and even long-distance airplane travel. However, the Hyperloop technology is not yet ready to be applied to real travel situations, and the infrastructure to support it, whether an elevated system or a tunnel, will have all the problems of building conventional high-speed rail on separate guideways, and will also be even more expensive, as a tube has to be constructed as well as the train.

Megaregions need fast enough trains now

Even if new technology someday creates long-distance passenger trains with travel times competitive with airplanes, passenger traffic will still benefit from upgrading rail service to fast-enough trains for many of the trips within a megaregion, now and in the future. States already have the responsibility of financing passenger trains in megaregion rail corridors. Section 209 of the federal Passenger Rail Investment and Improvement Act of 2008 requires states to pay 85 percent of operating costs for all Amtrak routes of less than 750 miles (the legislation exempts the Northeast Corridor) as well as capital maintenance costs of the Amtrak equipment they use, plus support costs for such programs as safety and marketing. 

California’s Caltrans and Capitol Corridor Joint Powers Authority, Connecticut, Indiana, Illinois, Maine’s Northern New England Passenger Rail Authority, Massachusetts, Michigan, Missouri, New York, North Carolina, Oklahoma, Oregon, Pennsylvania, Texas, Vermont, Virginia, Washington, and Wisconsin all have agreements with Amtrak to operate their state corridor services. Amtrak has agreements with the freight railroads that own the tracks, and by law, its operations have priority over freight trains.

At present it appears that upgrading these corridor services to fast-enough trains will also be primarily the responsibility of the states, although they may be able to receive federal grants and loans. The track improvements being financed by the State of Michigan are an example of the way a state can take control over rail service. These tracks will eventually be part of 110-mile-per-hour service between Chicago and Detroit, with commitments from not just Michigan but also Illinois and Indiana. Fast-enough service between Chicago and Detroit could become a major organizer in an evolving megaregion, with stops at key cities along the way, including Kalamazoo, Battle Creek, and Ann Arbor. 

Cooperation among states for faster train service requires formal agreements, in this case, the Midwest Interstate Passenger Rail Compact. The participants are Illinois, Indiana, Kansas, Michigan, Minnesota, Missouri, Nebraska, North Dakota, Ohio, and Wisconsin. There is also an advocacy organization to support the objectives of the compact, the Midwest Interstate Passenger Rail Commission.

States could, in future, reach operating agreements with a private company such as Virgin Trains USA, but the private company would have to negotiate its own agreement with the freight railroads, and also negotiate its own dispatching priorities. Virgin Trains says in its prospectus that it can finance track improvements itself. If the Virgin Trains service in Florida proves to be profitable, it could lead to other private investments in fast-enough trains.

Jonathan Barnett is an emeritus Professor of Practice in City and Regional Planning, and former director of the Urban Design Program, at the University of Pennsylvania. 

This is an extract from “Designing the Megaregion: Meeting Urban Challenges at a New Scale”, published now by Island Press. You can find out more here.