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Cinderella Trail has several steep sections that periodically
show some gullying erosion. This is the product of fast-moving water on
grades of over 15%. All users who use such steep trails will loosen surface
soils that will potentially become sedimentary, silting, runoff when the
rains come. The answer to this type of problem is to cover the steep areas
with water bars that catch the run-off soils before they reach the streambeds
below the trail. Much of this type of trail work is done by the Bicycle
Trails Council of the East Bay. This picture is
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of a wash out on Sunset Trail at the end of Cinderella Trail.
It was caused by a flood of rainwater that brought down a landslide from
the top of the park on Castle Park Trail. The following is a description
of trail work done by BTCEB where a section of Cinderella that had been
completely inundated by this same flood and landslide was completely repaired
in one afternoon.
A major landslide from the canyon on Castle Park Trail at
Castle Drive had filled the streambed on the uphill side of the 3 foot
culvert and buried it. The stream now washed straight over the trail and
was washing massive siltation down into the creek. The run-off was heavily
eroding the trail away from the downhill side. To make matters worse,
the entire trail was flooded for the length of 10 feet. The initial solution
was to dig out the culvert and expose the buried entry point, which was
a fine idea until we discovered "The Rock." A boulder estimated to weigh
between 500 and 600 pounds was part of the culvert blockage, and was a
big contributor to the buildup of clogging debris. While we cleared the
area around The Rock, we were able to utilize the extremely rocky removals
for fill on the eroded side. Careful placement of large, medium and small
rocks and the gravel fill allowed us to rebuild the missing part of the
trail and to cover over the downhill side of the culvert which had been
exposed up to about eight feet by the massive erosion of the hillside
by the flood. Meanwhile, we were able to scrounge up some long branches
for levers, which were cut on a city project up the hill and which had
managed to wash down to our project area. With these fine levers, we started
on The Rock. Through much muscle and much more leverage, the boulder was
lifted out of its resting-place and brought up onto the trail, which allowed
a real cleaning of the culvert. With the major obstruction removed, every
bit of debris could be removed from the culvert and the stream flow was
restored to its proper path. This stopped the huge siltation caused by
eroding the trail and saved the trail bed itself. After solving the big
problem we posed the Rock on the downhill side of the trail and smoothed
the trail surface around the corner over the culvert. This section of
the trail should be permanently fixed and need only a little clearing
going forward.
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