The Island Packet: Cyclist safety suffers setback with SC 46 rumble strips
September 29, 2012
The four-foot wide shoulders along S.C. 46 were a result of lobbying by local bicycling advocates in 2004.
Bicyclists wanted a safer ride down the scenic two-lane road and a link to bicycle paths still to be built along Buckwalter and Bluffton parkways.
It was so important to the community that when the paving project that included the wider shoulders fell a foot short of the four-foot goal, local elected officials got out a measuring tape to confirm their suspicions and then insisted the work be redone.
The state Department of Transportation brought back the contractor and got that extra foot of pavement — at an additional cost of $260,000 for the $1.3 million repaving project.
That history makes all the more puzzling its decision to gouge 16-inch-wide rumble strips into the road’s shoulders without talking to cycling groups or at least notifying them of the pending work. Bicyclists had already complained about similar work on S.C. 170, whose wider shoulders also were a result of a push by local cyclists.
The rumble strips do provide a measure of safety for bicyclists. Vehicles drifting across the white line into the shoulder pose a risk. The strips alert drivers that they are straying. But the strips are extremely jarring for cyclists, putting them at risk of a serious fall, and they reduce maneuverability for debris and other hazards found along the road. That includes broken-down vehicles, fallen branches and large clumps of mown grass left from roadside maintenance, as well as grass that has been allowed to grow into the shoulder. There’s no way to move smoothly into the lane nor to ride on or near the white line even for a short distance to avoid roadside hazards.
It’s almost certain that some compromise could have been worked out to balance motorist and bicyclist safety.
Engineering guidelines state that rumble strips should be placed on shoulders of roads that are classified as rural, with average daily traffic of at least 500 vehicles and a 45 mph speed limit. The milled-in rumble strips, like those on S.C. 46, are to be used on roads with a shoulder of four feet or wider.
Roads with narrower shoulders can be fitted with rumble strips with skip patterns or plastic markings, the guidelines state. That should extend to roads with shoulders aimed at providing a safer route for bicyclists, such as S.C. 46.
Transportation officials say rumble strips are not placed on roads that are part of the statewide bicycle touring route. S.C. 46 isn’t part of that route, but it should be.
And that guideline recognizes how hazardous rumble strips can be for bicyclists.
The state went to extra expense to provide safer passage for bicyclists. It shouldn’t have undone that good work with rumble strips when other solutions for motorists’ safety were available. Department officials should look for just such a solution and fix their mistake.
