Sidewalk riding is always a controversial topic. It’s legal in a surprising number of places, though the fact that it’s legal is no indication of whether or not it’s a safe practice. I feel sidewalk riding can be relatively safe in certain circumstances and when approached with a certain mindset, but I often see bicyclists on sidewalks riding in ways that are dangerous to themselves and others.
One of the main issues with sidewalk riding is that motorists don’t expect to encounter vehicles traveling at close to motor vehicle speeds anywhere other than in the road. We’re all accustomed to looking in certain directions at certain times while riding or driving, and anything that doesn’t fall within normal traffic patterns runs the risk of being overlooked. Consequently, bicyclists traveling at anything over walking speed on sidewalks are in danger of having vehicles pull into their path at intersections and driveways.
Likewise, pedestrians are only accustomed to sharing the sidewalk with other pedestrians. Because they’re not expecting a bicycle to come up from behind, they have no reason to maintain a perfectly straight path, so there’s potential for collisions there as well. While collisions with pedestrians are not as dangerous as collisions with motor vehicles (obviously), these negative sidewalk encounters reflect badly on bicyclists in general.
In my hometown, we have a number of high-speed parkways with 2-3 lanes running in each direction. These roads have a center median and wide sidewalks on both sides that are separated from the traffic lanes by grass buffers. The only side streets are major intersections or entrances to neighborhoods. No residential driveways enter these roads. The sidewalks are wide enough that they could easily be considered separated bike paths. The lack of driveways and minimal cross streets make these pseudo multi-use paths safer and more useful for bicyclists than most sidewalks.
On the other side of the coin, we have sidewalks inside residential neighborhoods that are lined with parked cars and criss-crossed with driveways, cross streets, and alleys. They’re also often filled with small children, dog walkers, and skateboarders. Certainly, everyone can agree bicycling on these types of sidewalks is not a good idea.
As I see it, the only way to safely ride on a sidewalk is to act as a pedestrian anytime we’re near a pedestrian or an intersection. That means riding at walking speeds while in the presence of pedestrians, and it means slowing or stopping at intersections, driveways, and alleys to look in all directions (including behind) before crossing. Other than in certain special circumstances such as those along our parkways, I think most bicyclists would find the above approach barely workable. Unfortuantely, any other approach to sidewalk riding may be an invitation to conflict or even injury.