A famous trail builder once said, "There are three deadly enemies of all trails. Those are rain, rain, and rain." Back on February 11 thru the 14th, 2000 the Oakland East Bay basin received over 5 inches of rain fall. In a single day, February 13th, over 3 inches (and probably a fair amount more in the hills) fell in Oakland. Before this rain (and these photos) the Upper Meadow showed no signs of erosion and was a pristine green lawn. Rain did more damage in those three days than all the users did to the meadow in all its years combined.

Twenty-four inches of erosion in three days! Proponents of the bike ban have often used photo like this to demonstrate measured erosion on the trails. Write ups in the local newspaper and photo wielding "environmentalists" at City Council meetings have attempted to scapegoat mountain bikers for all erosion damage in the park. However, almost all of the " gullying" erosion problems represent the effect of rain water flooding and poor trail design.

Bikes are not the only source of erosion in the park. Horses, hikers, kids playing, people taking shortcuts, maintenance procedures, and every human process from picnicking to naturalist-led hikes causes some degree of effect on the resource. However, as you can see here, ten years, with thousands of bikes riding through the Upper Meadow, and every possible recreational activity from Frisbee throwing to baseball, was far less devastating than a week of hard rain.

During the storm floodwaters followed the course of the natural streambed (now underground) and dug a deep channel past the picnic tables.