The Bicycle Network
A proper bicycle network is comprised of four basic types of bikeways: bicycle lanes, bicycle boulevards, shared streets and off-street paths. Although bicycle use is not common in many American cities, planners and government officials must acknowledge that such activity is unlikely to increase without a sufficient bicycle network in place. Cities and towns interested in developing or expanding their bicycle network must consider plans that include all four types. Doing so creates a tapestry of options for the three types of bicyclists and their individual requirements (outlined in my previous post). Portland, Oregon and Berkeley, California experience some of the highest bicycle mode shares in the country precisely because they use a layered approach. Before continuing, it's important to loosely define each bikeway type.
Bicycle lanes are dedicated 4' – 6' wide travel lanes demarcated by 8" striping, or physical barriers such as bollards. Regardless, they are most appropriate for medium-speed thoroughfares. To increase their visibility, they are commonly painted red, blue, or green.
A bicycle boulevard functions as a preferred through street for bicycles. The implementation of traffic-calming devices along local streets with low traffic volumes whenever possible, prioritizes the free-flow of bicycles, and assigns the right-of-way to the bicyclist at intersections. Again, Portland, Oregon and Berkeley, California have successfully implemented bicycle boulevards, greatly expanding the appeal of their bicycle network.
Shared roadways- the majority of thoroughfares- are usually low-speed, low-flow intra-neighborhood streets, or vibrant mixed-use commercial streets bicyclists safely share with slow-moving traffic.
An off-street path may
exist within the road right-of-way or within an independent right-of-way, but is
always physically separated from motorized vehicular traffic. Paths are typically
paved, especially in urban areas, and most often feature dual
direction movement. Although bicycle paths are used for recreation in
areas more rural in character, they are also used for recreationand commuting in places
that are more urban. For safety reasons, most paths feature
directional signage and a few are even signalized where the bicycle path
intersects with regular thoroughfares.
While not every roadway provides excellent bicycling conditions, a complete bikeway network should provide efficient regional access. The first step towards achieving this goal is to map the existing network. This includes existing facilities and those bicycle "desire lines" where none are currently present. The network should then be complemented with a new plan, which aims to expand bicycle facilities and link important destinations in a contextually appropriate manner.
A good bicycle network is also supplemented with secure bicycle parking facilities along important commercial corridors, at transit stops, and near major civic, educational, and employment centers. When feasible, such destinations should also be served by shower/changing rooms, which may be facilitated by building codes that comply with LEED standards, especially at government and civic buildings. Bike lockers, like those in Ann Arbor, or bicycle stations such as those in Chicago, Seattle or Santa Barbara, provide downtown commuters and recreational riders with secure bicycle storage, showers and repair services. More of these should be built in urban cores, preferably at transportation nodes and civic spaces like parks and squares.
Additional on-street bikeway enhancements include clear signage specifying the distances to major destinations, wide shoulders, sharrows and bicycle boxes. Still in their early stages, sharrows and bicycle boxes as well as wide shoulders are being implemented with success and should be considered as tools capable of producing a finer grain of contextually appropriate bicycle facilities. Explanations are below.
Sharrows are an experimental on-pavement marking of a directional arrow or "chevron," and a bicycle symbol identical to those seen in bicycle lanes. Sharrows demonstrate that bicyclists should "take the lane" by directing them into safe, shared-lane positioning. Studieshave proven that the sharrow effectively reduces bicyclist/motorist conflict along medium-speed thoroughfares and help bicyclists safely avoid the door-zone. Sharrows are appropriate wherever travel lanes are too dangerous to share safely and when bicycle lanes are not feasible due to available street width or the general character of the street. As such, they are a great tool for mixed-use pedestrian oriented districts as the continuation of bicycle lanes that run through those urban areas less saturated with pedestrian activity. Just as highways should stop before entering the city, so too should bicycle lanes when entering the most pedestrian-oriented, mixed-use streets.
The bicycle box is an intersection safety design tool used to prevent bicycle/car collisions, especially those between drivers turning right and bicyclists traveling straight via a bicycle lane. The bicycle box guides bicyclists to move left, effectively taking the motor vehicle travel lane during stop lights. A colored (typically green or blue) on-pavement marking, this tool is further marked by a white bicycle stencil located inside the box. During a green light, the colored bicycle lane leading to and from the intersection reminds motorists and bicyclists to safely acknowledge the other. Since they typically accelerate faster through intersections than automobiles, bicyclists will likely be through the intersection and have returned to the appropriate lane position by the time a car is ready to overtake him or her. Brooklyn is among a handful of large American cities successfully supplementing their bicycle network with bicycle boxes.
Wide shoulders are often used by opportunistic bicyclists as a way to claim space, and therefore a sense of safety and comfort. Typically 4' or more, wide shoulders most often exist on those thoroughfares which pass through a more rural context, or along scenic urban thoroughfares, such as a waterside drive. However, some residential urban thoroughfares without parallel or head-in parking are wide enough to accommodate bicyclists riding along the shoulder, although narrowing such streets is preferred. In a more urban context, planners and engineers should generally not include shoulders when retrofitting existing streets, as wider streets correlate strongly with higher motor vehicle speeds and pedestrian unfriendliness.
Design For Context
Having already alluded to the importance of contextual bicycle planning, I should be more specific. When designing a bicycle network, it is important to maintain a holistic understanding of urbanism and what makes active, safe and pedestrian-oriented neighborhoods. Unfortunately, over the past 60 years, overt specialization within the planning field has separated planners into individual silos of expertise where they have lost sight of the larger picture. Though traffic engineers and many transportation planners are notorious for their myopic auto-centrism, this does not discount the same narrow scope respective to alternative transportation advocates, architects or environmental planners. Although this trend cannot be overcome simply through the discipline of bikeway planning, I would recommend that those involved with bicycle facility design assign priority in the following order:
3) Motor Vehicles
Recognizing this hierarchy means that bicycle facilities should not trump the pedestrian experience. It also means that a full range of tools must be available so that planners and designers meet the three types of bicyclists' needs and appropriately respond to urban context. The four types of bikeways and the additional tools described above, along with the simple chart below, will help planners to match thoroughfare type and context with the proper bicycle facility.
It is important to also note that urban context varies not only within cities, but also along individual corridors. In Miami, Northeast 2nd Avenue provides a perfect example of context transition. While a bicycle lane makes sense along most of the corridor (one is currently planned), such a facility should yield to the pedestrian, mixed-use-character of the Design District in which it bisects. In this situation a seamless transition from bicycle lane to sharrow provides for a contextually appropriate and fine-grained facility design solution that maintains the narrow street width, as well as the precious on-street parallel parking spots coveted by retailers and restaurants, which the proposed bicycle lane threatens to replace.
A summary of thoroughfare types, using SmartCode nomenclature is below. Calibration to local conditions will be required, but the table provides a quick and simple way to think about bicycle facilities and their appropriate context. One could easily complete a similiar table for bicycle parking and other such facilities, especially as it relates to the urban-to-rural transect- a comprehensive planning tool on which the SmartCode is based.
Because most cities have so little bicycle infrastructure in place, it is imperative that the first foray into facility expansion provides useful, safe, contextually appropriate and connected facilities. In reference to the above, those places where short term gains can be had should be prioritized. Although bicycle improvements should be planned efficiently and concurrent with other street resurfacing, drainage, widening, or dieting projects, engineers and planners must not rule out the possibility of road construction projects designed specifically for bicycle facility and infrastructure expansion. This is especially true for bicycle boulevards, which may make sense along streets that do not need resurfacing, but still require a detailed level of infrastructure construction for traffic-calming, signage and pavement markings. Thus, governments must set aside money for this purpose and advocacy organizations must work with them to help prioritize the projects that carry the most merit.
Putting these priorities in place will help municipalities avoid a disconnected, unsafe and relatively useless system.
Rome was not built in a day, and neither were the world's most progressive bikeway systems. Indeed, did you know that in the 1950's Copenhagen was well on its way to becoming as autocentric as any American city? It was. To avoid such a disaster, planners, government officials and citizens shifted priorities and began slowly replacing auto-oriented infrastructure with transit and bicycle infrastructure. To their credit, Copenhagen is now the most advanced bicycle city in the world. Your city may not be the next Copenhagen just yet, but with the right approach it may be the next Portland.