Bicycle Trails
Recent decades have seen an explosion of interest in cycling, both street-type and off-road type. Many graded, surfaced bike paths have been built, but especially popular is the off-road, or mountain biking. A common term for these facilities is simply “bike trail”. These trails may be built to a different set of standards than foot trails, requiring more stable, harder surfaces, less strenuous grades, longer sight visibility, and less sharp changes in direction. On the other hand, the cross-slope of a bike trail may be significantly greater than a foot trail, and the actual treadway may be narrower in some cases.
A particular offshoot of trail biking is downhilling, which can be environmentally destructive if not well-managed. Downhilling is particularly popular at ski resorts such as Mammoth Mountain in California or Whistler in British Columbia, where ski lifts are used to get bikes and riders to the top of the mountain.
Because of the greater need for more gradual grades, changing elevations may involve sidehill trails with multiple switchbacks, while these may not be necessary for hikers. In cases where hikers use these bike trails, attention must be paid to the potential of cutting across switchbacks.
Where bike trails intersect with pedestrian or equestrian trails, signage at the intersections is important, and high visibility onto the intersecting trails must be a priority in order to prevent collisions between fast-moving cyclists and slower moving hikers and horses. Bicycles and horses should be allowed on the same trails where the trail is wide enough with good visibility.
A well designed bike trail will have an average grade of less than 10%, and will generally follow a countour line, rather than straight downhill. The trail should slope out or accross the trail 3-5% downhill to encourage water to run off the side, rather than down the trail bed. In addition, frequent grade reversals also prevent water from running down the trail, make the trail more fun and interesting to ride, and generally help keep bike speeds down, providing a more safe trail experience for all users.
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