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Bicycle Safety Options on Highways
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Highway safety for bicycles is a growing concern that has become a focus of the PCH Safety Committee organized by Senator Fran Pavely and Assemblymember Richard Bloom. Their leadership has made it possible to bring bicycle safety to the center of the planning process from Santa Monica to the Ventura line.
That effort and the strong leadership and bicycle safety ideas from safety Commissioner Meril May stimulated discussions in various bicycle communities including the ones in LA and Santa Barbara. The combined contribution of these groups has created some solid ideas about improving the safety on all highways including the ones that run through the cities, rural areas and mountains. This report provides some of those ideas. You are invited to add more to this list and give feedback.
There are design elements that can be added to highways to improve bicycles safety. The appropriate elements vary based on the size of the highway and the speed of the vehicle traffic. The primary goal is to have fully secured bicycle lanes on ever stretch of highway that does not have a safe parallel route for bicycles to use. Given the constraints in attaining that goal there are some other ways to increase highway safety for bicycles. Here is a summary of some of these elements.
Highway Shoulder Considerations
All highways need a line marking the transition between the shoulder and the first full width traffic lane. This will be referred to as the fog line in this discussion.
Bicyclists benefit from having as much smooth paved surface to the right of this line as possible. The minimum width needed for bicycles to be able to ride on the shoulder is two feet of pavement, three feet becomes a safer riding surface and four feet allows for a bicycle lane.
Bicyclists also need this paved area to be free of bumps, holes and gravel. Regular maintenance and sweeping with a street sweeping broom is needed for this area.
There is another shoulder safety consideration when the shoulder of the road includes a flat gravel surface. The concern is that the transition from the paved surface to the gravel be as safe as possible. This means having the paved and gravel surface make a smooth transition that is level and as free of ruts, grooves, bumps and holes as possible. This helps bicyclist in two ways. One is to provide an emergency escape option onto the gravel that maximizes the ability to maintain control. It also allows cars to move onto the shoulder more effectively and completely. This means that cars are less likely to park or drive on the paved shoulder which leaves as much room for bicycles to ride as safely as possible.
There is a similar concern when a paved shoulder has a concrete skirt or gutter. The transition between the asphalt and the concrete needs all the safety features described for a paving to gravel transition.
There is another shoulder safety feature that would help on highway sections where cars park on a regular basis. That would be to add a car parking limit line inside the fog line whenever there is at least three feet to spare between a parked car and the fog line. This line would be used to keep cars, warning signs and trash containers out of the prime bicycle riding area. It may need to have some feature to keep that line from being confused with lines that create a full on bicycle lane. Perhaps a dashed line would work.
Keeping temporary warning signs out of the bicycle riding areas would also be helpful. It does not make sense to force bicyclists into traffic when trying to create a safety result. Crews can benefit from better sign technology to create this. A simple device to help balance signs on raised surfaces like curbs would help. Guidelines and training for sign placement that include bicycle safety concerns are needed.
Links to help others find this information
Both cars and bicycles can move from the full width lanes to the shoulder and visa versa. When done intentionally and with proper signaling this should be reasonably safe. When done by casual drifting from one to the other it can be very dangerous – particularly when done by a large vehicle.
There are two features that can be added to protect against this sort of hazard. One would be to use reflective road dots either on or to the left of the fog line. These would need to be placed far enough apart so that they do not become bicycle hazards and close enough that cars would feel them strongly enough to know they are drifting onto the shoulder. These would probably be most effective with traffic speeds in excess of 35 mph and may be beneficial for all streets with a fog line. It would not be appropriate to use these when the paved shoulder is less than two feet wide.
The other feature is the so called rumble strip. This refers to a line of grooves cut perpendicular to the road. Placing these to the left of the fog line would warn cars they are near the shoulder. These are a hazard for bicycles to cross. This means that they would only be appropriate when bicycles have three or more feet of paved surface to the right of the rumble strip at all times. It also suggests that using these when there is high speed traffic makes it necessary would be best. That probably means areas with speed limits of 55 mph or higher.
Copyright 2014 Russell Sydney, All rights reserved.
Lane Changing Warnings
There are only certain highway locations where there is adequate room coupled with potential rider demand to overcome the resistance to creating a dedicated bike lane. In those locations, the safety of the bicycle lane would be greatly improved if the lane is built as a separated lane. Separated bike lanes are on-street lanes separated from traffic by curbs, planters, parked cars, or posts. A report has just been released with solid safety data on this approach. That report available from the link below, shows substantial safety benefits from separated lanes and calls for using them as a standard at least in urban settings.
Please review and critique these safety considerations. It would also be helpful to get feedback on how best to use these guidelines and ways to implement them.
Please send comments to Main@sustainableclub.org or call Russell Sydney at 805-652-1482 to provide feedback and suggestions.
Bike Lane Option