DEL MAR — City Council unanimously authorized modifications to the encroachment permit for Crest Rim following a March 8 bluff failure at the site.
“This was not a totally unexpected event,” said Linda Chisari of the Del Mar Garden Club, which maintains the area.
When park designs were under way last summer, David Skelly, a civil engineer with GeoSoils Inc., predicted a 30-foot portion of an overhanging cliff with a 5-foot undercut was likely to experience a failure at some point, Chisari said at the April 6 City Council meeting.
Anticipating the collapse, Skelly positioned the walking path 10 feet from the edge of the bluff that was undercut. In areas that were not undercut, the path that winds through the park is 5 feet from the edge.
Where the failure occurred, the path is currently 12 to 18 inches from the edge. Skelly visited the site March 20 and recommended moving the path so it is 5 feet from the edge of the cliff, which is no longer undercut.
The adjusted path will still provide sufficient room in front of the benches, however, the rock retaining wall must be pushed back a few inches for wheelchair accessibility.
Skelly did not recommend installing a rail. “He felt that it was not necessary and that drilling holes into the ground could accelerate any further erosion,” Chisari said.
The changes were previously reviewed and approved by the Parks and Recreation Committee. The Garden Club measures the distance from the edge of the path to the edge of the cliff once a year to monitor erosion. The last bluff failure in that area was more than 25 years ago.
The one-day project cost is estimated at about $600, which will be funded by Garden Club donations. Warning signs are up and as long as people stay on the path, they should be safe, Public Works Director David Scherer said.
There is another portion of the stretch with an undercut section, but the path is farther back from it so if it does fail “we should still be in pretty good shape,” Scherer said.