Bermuda Avenue, San Diego
Project: Coastal Bluff Seawall With Tiebacks
Client: Homeowner
Location: San Diego, CA
Design Engineer and Contractor:
Soil Engineering Construction, Inc.
Government Permit Agent:
The Trettin Company
Geotechnical Consultant:
Project Description:
As the site of one of the oldest homes in the San Diego community of Ocean Beach, the subject property had prior bluff protection work dating back to the 1920's, with permitted rip-rap being placed on the beach in the 1980's. The near total collapse of a decades old seawall and the displacement of existing rip-rap created a need for revised bluff protection along this multi-property project in which the homes are adjacent to one of the few remaining pocket coves in San Diego County open for public use. A significant failure at the southern end of the property necessitated a segment of the project to be constructed under emergency permitting.
The project included removing all of the old, failing bluff protective measures and restoring more than 2500 sq. ft. of beach for public access. A seawall, approximately 245' long and ranging in height from 21' to 26', was designed for construction immediately adjacent to the failing bluff. To preserve a public beach access stairway on adjacent city property, an 18' long lateral return wall extending to the west was included in the project scope. The project included the installation of 65 tiebacks to a depth of +/- 45 feet and the application of hand-sculpted, color-treated structural shotcrete.
In addition to the initial emergency permitting for the southerly failure area of the project, the applicant was also required to obtain a Coastal Development Permit and Special Use Permit from the City of San Diego. This posed a unique challenge because the existing rip-rap adjacent to the northerly portions of the site, although inadequate, protected the residences sufficiently to eliminate the finding that an emergency existed – which was necessary for permit issuance. Extensive work with California Coastal Commission and city staff, and environmental activists, resulted in such significant project support that the city made a determination to grant a waiver for the project that allowed permitting to proceed successfully.
Coastal Bluff Stabilization (245')
Seawall Coverage: +/- 3,500 Sq. Ft.
65 Drilled Tiebacks / Multi-Strand Anchors
Epoxy-Coated Steel Reinforcement
Hand-Sculpted / Color-Treated Shotcrete Finish
Removal of Existing Rip Rap and Remnants of Old Seawall (+/- 300 tons)
Restoration of +/- 2500 Sq. Ft. of Public Beach