12′ High Seawall for City of Pacifica, Calif. Installed 1989

Pacifica, Calif.

Unique Features:

The precast wall was an alternate in the Woodward-Clyde bid package and was selected by Granite Construction over the MSE wall alternate. An integral wave deflector was monolithically cast with the top wall panels instead of the field cast cap that was shown for the MSE wall.

Prior to the wall installation a trench was cut into the slope and a cip cut off wall was constructed behind rip rap. The precast wall components were then installed. Since sand was used for wall fill filter fabric/geotextiles were placed over the fill side of the precast elements.

The wall has been subjected to many extreme load conditions compared to a typical seawall/erosion control structure. Locals claim that the tallest wave ever recorded in North America occurred at Pacifica. There are shots of these giant waves at local establishments. Some smaller waves are shown crashing into the wall in the shots.

Also the wall was impacted by the San Francisco earthquake which hit shortly after the wall was completed. The existing MSE wall north of the fishing pier has not fared so well. We understand that due to the corrosion of the metal soil reinforcement and movement fill has been lost from behind the wall. To address this issue the city has apparently refilled voids with concrete fill. There have been no issues with the Stresswall Structure.

Area City of Pacifica Client Scope Of Work

Sorrento Valley Alternating Panel Improvement Wall

Sorrento Valley, Calif.

Unique Features:

By utilizing the “slot cut” installation method temporary shoring was eliminated that would have been requires for other wall types.  Therefore the overall wall cost and construction time was greatly reduced compared to other wall options.

Area Noveco Inc. Client Cut Wall w/o shoring Scope Of Work

40′ High Apache Trail Access Road


Unique Features:

This project is the result of a VECP proposed to the Bureau of Reclamation by the contractor.  The wall  supports the access road to the Theodore Roosevelt Dam Power Station.

The original design was a typical massive cip wall.  Field testing determined that ground anchors would be required to both pre-compress the insitu soil as well as enhance wall stability.  Therefore the wall has a unique foundation configuration.  By including a cip grade beam with vertically oriented mini piles over which the counterforts were placed provided adequate foundation bearing capacity for the wall.  In addition, following placement of the base counterforts, ground anchors (tie backs) where inserted through the cip grade beam that was cast over the tails of the counterforts.

Following the installation of the base tiers and anchors the subsequent upper tier components were placed.  Site excavated cut material was used for wall fill.

Area Bureau of Reclamation Client Scope Of Work