The project involves the removal and abandonment of a failed 24-inch storm drain corrugated metal pipe (CMP), repair of extensive erosion around the failed pipe, and installation of a new 24-inch reinforced concrete pipe (RCP). Seventy-five feet of the failed 24-inch CMP would be slurry filled and abandoned, while 40 ft. of the CMP will be removed. The failed slope will be graded and filled using a combination of geogrid material (placed below the soil surface to provide structural integrity) and clean fill. The 200 ft. of new RCP would be installed approximately 100 to 150 ft. to the west and southwest of the failed CMP. The project also includes the removal of approximately 140 ft. of sidewalks and 25 ft. of curbs and gutters and the installation of 80 ft. of sidewalk and 45 ft. of curb and gutter. The new pipe would connect to the same inlet location as the failed CMP (at the north end of Miracle Drive), and then head west and discharge near the bottom of the canyon slope into an existing drainage channel. The new pipe would be placed below ground in an excavated trench, with cutoff walls spaced at approximately 15 foot intervals to stabilize the pipe within the hillside. A concrete energy dissipater structure and 9' x 8' of rip rap would be installed at the downstream end of the pipe to reduce discharge to non-erodible velocities. An approved erosion control revegetation plan addresses areas impacted by the project and the stabilization of the disturbed areas with native species appropriate to the surrounding areas. Staging for the project would be located within the street at the end of Miracle Drive. The project also includes a Traffic Control plan.
Other (Removal and installation of a storm drian and erosion repair)
Other ActionOther Action: Site Development Permit
Biological ResourcesLand Use
Air Resources BoardCalifornia Department of Parks and RecreationCalifornia Highway PatrolCaltrans, District 11Department of ConservationDepartment of Water ResourcesNative American Heritage CommissionRegional Water Quality Control Board, Region 9Resources AgencyState Water Resources Control Board, Division of Water RightsDepartment of Fish and Wildlife, Region 5