March 27, 2000

Board of Directors

East Bay Regional Park District

2950 Peralta Oaks Court

P.O. Box 5381

Oakland, California 94605-0381

Re: Mountain Biking in Pleasanton Ridge Regional Park


Pleasanton Ridge Regional Park has a reputation as a "mountain biking-friendly" park. I wanted to see what effect that has had on the park. I also heard that the narrow portion of Sinbad Creek Trail, which was opened to mountain biking so that bikers could reach the north end of the park (with their bikes) is damaged, and needs repair.

I hiked almost the entire length of the park yesterday, from the Oak Tree Staging Area to the gate (marked "32" on your map) at the north end of the park, looking for damage from mountain biking. It took me about seven hours, and my feet were very sore! Now I understand why people mountain bike!

Actually, I think that being able to traverse the park quicker is no excuse for allowing the kind of damage that mountain biking does. Once when I was a kid, hiking on a long, boring portion of a trail, it occurred to me that it would be nice to have a bike with me, so that I could get past the boring portion and on to the interesting part, faster. But about one second later, I realized that if I could bike there, so could everyone else, and the place would soon be overrun with people. And that is exactly what happens to every park that is opened to mountain biking.

I was only in the park for a few seconds, before I saw the first mountain biker riding off-trail (next to the fence to the left of the trails). I also saw (and photographed) a biker riding up a cow path a few yards north of marker #22. Throughout the park, I saw bike tracks going off the trail, in several cases right next to signs saying "Stay on the Trail". Since Pleasanton Ridge is one of the most bike-friendly parks in the Bay Area, and every trail in the park except one tiny hiking/horse trail and one tiny horse trail are open to bikes, it is amazing that they still aren't satisfied, and insist on riding illegally!

Besides widening trails and creating new, illegal trails, the bikers have also ridden during wet conditions, creating a "moonscape" of hard ridges that are impossible to walk on. And on the narrow ("singletrack") portion of the Sinbad Creek Trail, they have turned the trail into a "V" groove that is dangerous or impossible to hike on. Other portions of that trail have been turned into a groove that is too narrow to hike in. On one switchback ("hairpin") turn, tree roots were exposed and probably killed, due to the great amount of erosion. Mountain bikers claim that "responsible" riders don't skid, but I saw several places where riders had skidded and ripped off the protective duff, all the way down to the bare dirt. To be honest, it is impossible to ride on steep or loose soil without skidding. In seven hours of hiking, I did not see a single ranger or other park district employee, which is probably one reason why the mountain bikers were so brazen.

Distinct from the mountain bike damage, I also saw a lot of holes punched by horse's hooves, some of it on the edge of the trail or off of the trail. I don't know how much of that is due to wearing horseshoes, and how much is due to the wet conditions. There was far less of that, and I was always able to hike around it, but it does make that part of the trail hazardous to walk on. However, horses are not native to this area, and I don't believe in using animals as vehicles. Like mountain bikes, they make it much easier for people to get to remote areas, which, due to their remoteness from humans, are important to wildlife.

By far the most damage is being done by cattle. Not only do they turn wet trails into unwalkable "moonscape", but they damage the creeks, destroy riparian habitat, create new trails that are a temptation to mountain bikers and others, and apparently eat all the oak seedlings. When the gorgeous but aged oaks in the park die, there will be none to replace them. This is an enormous problem in California, and may lead to the extinction of some species, if it hasn't already. Also, the exotic grasses brought here to feed the cattle have taken over most of the open areas of the park, pushing out the native grasses and creating an enormous fire hazard (native bunch grasses are much less flammable, partly because they leave gaps between the bunches). The park badly needs to have the exotic grasses burned out and the native species restored.

Aesthetically, most of the park has the feel of a working ranch or a mountain biking track, not a natural park. It is impossible to relax, knowing that people could speed by on large pieces of machinery (something I go to the park to get away from) at any moment. Even the experience of being on a ranch is far inferior to the experience of the peaceful, gorgeous, complex ecosystems that make a park a true refuge from the stresses of city life.

Please remove the bikes and cattle! Like cars and other motor vehicles, they have no place in our parks.


Michael J. Vandeman, Ph.D.

P.S. I hiked the entire Woodland, Ridgeline, Sinbad, and Bay Leaf Trails. I will soon have numerous photographs of the damage to show you, if you would like to see them. For more information on the harm that mountain biking does, see