Backcountry trails in U.S. national parks, such as Yellowstone and Yosemite, have traditionally been open only to hikers and horses, not mountain bikes. At the urging of President G.W. Bush, an avid mountain biker, the park service is considering opening some trails to mounpptain bikes and creating some mountain-bike-specific trails, such as one in Big Bend National Park. This issue is controversial, with opponents claiming that mountain bikes create trail erosion and trample native plants. They also claim that mountain bikers disturb wildlife and other park users, such as hikers, birders, and equestrians. Mountain bike proponents point out that properly designed mountain bike trails do not create erosion and that research shows that mountain bikes do not damage trails any more than hikers. Moreover, allowing mountain bikes in parks may help reverse declining trends in public visitation in many parks, while serving to spread out the impact of visitors across more of the parks.

Explain how the park service can use the principles of concurrent design to design trails that provide visitors with a high-quality experience while also protecting the natural resources within the park. Discuss another design tool or concept that could be brought to bear on this problem.