Do:
- Do allocate space on the roadway for cyclists. Cyclists move at closer to car speeds than pedestrian speeds, so have cyclists move in the same direction, and nearly the same place as other traffic. This makes them easier to spot, especially at intersections
- Do separate cyclists from parked cars, if possible. Drivers opening car doors into the path of cyclists is a significant cause of accidents. Use markings on the road to encourage cars to park close to the curb.
- Do put cycling paths off the road, but only if the distance between cross streets and driveways is big, say 1/4 mile (400 m). This is often possible in between a road and continuing obstruction, like a river, lake, or train line. Remember that every intersection between a cross street and a road/bike path poses a hazard to cyclists because drivers on the cross street will focus their attention on the road traffic rather than the trail traffic.
- Do walk the site, and bike it, before designing it. There is no better way to familiarize yourself with the nature and nuances of the site.
- Do as much of your commute as possible, as often as possible by bike. You wouldn't even think about designing roads if you weren't a driver. Likewise, to design safe cycling infrastructure you should be an experienced urban cyclist.
Don't:
- Don't put cyclists on the sidewalk. They will be much harder to spot at intersections, and much more easily hit by motorists. If space availability requires that the lane is on the sidewalk, put the lane as close to traffic as possible (to make it more visible), and use some kind of obstacle to separate cyclists from pedestrians. The exception is junctions are few and far between, which is rarely the case in an urban setting.
- Don't put visual obstacles (like trees, shrubs or parked cars) between the traffic and the cycling lane. To avoid hitting cyclists at intersections, motorists turning off the road have to be able to see them in the bike lane.
- Don't put combined pedestrian and cycling trails in busy urban areas. You can build a nice sidewalk, or a nice bike line, but you can't do both. On such trails, cyclists and pedestrians pose hazards to each other. Furthermore, moving as fast as they do, the cyclist are liable to be unseen, and therefore hit, by motorists.
- Don't build kamikaze (contraflow) lanes. Cyclists should always be to the right of the traffic (in countries that drive on the right hand side). It is fiercely dangerous to put cyclists to the left of traffic, because there is a high chance they won't be seen by motorists at intersections. Unfortunately, this is sometimes done on one way roads, where 99.9% of the traffic is moving one way, and less than 0.1% of traffic is encouraged to run the big risk of going against the flow.
- Don't put barriers between the road and the cycling lane, like curbs or bollards, if they will prevent snow clearing or street sweeping on the lane.
- Don't put cycling lanes on the biggest, busiest roads if there are quieter roads nearby. If you're an urban planner, keep this in mind and plan for the long run. If you're a civil engineer, speak up and push back if you're asked to put bike a lane on busy road.
- Don't rely on signs to remedy unsafe design practices. A sign may slightly reduce the risk of the bad design practices outlined above. But the proper solution is to avoid unsafe designs in the first place. Your highest priority as an engineer is to avoid killing or injuring people. So, do your best.
In future posts, I will illustrate and expand on these points, and add links from here. This guide is written for right hand traffic, as in the Americas and continental Europe. Naturally, for left hand traffic, as in the UK, Japan, and many Commonwealth nations, left and right will be reversed.
