Taming Devil’s Slide

November 10, 2012by The Conco Companies

The natural beauty of the Northern California coastline has sometimes wreaked havoc on the coastal communities of Moss Beach and Montara. During the rainy season, mud slides become a frequent occurrence often leading to the shutdown of Highway 1, the only artery leading north to San Francisco.

The resolution to this problem was to build a tunnel through the mountain that will bypass the parts of the coastline most prone to erosion. Public input from local residents reflected a high level of concern that the fix not detract from the natural beauty of the California coastline. Therefore, great attention was made to make sure the tunnel blended in with its surroundings.

Robert T. Hill & Associates, a well-respected artistic firm with 25 of years experience in concrete sculpture, teamed up with Conco on this high profile project. The task at hand was to reconstruct boulder formations out of concrete to blend into the natural formation that existed above the Portal at the south end of the tunnel.

The project was designed by Cal Trans in 2006, but not started until March 1, 2012. Applying shotcrete was extremely difficult as the grade was at 1 to 1 ½ slope. This required the use of man lifts and cranes and sometimes having crews tied off from the top and rappelling down from the top.

The tunnel is scheduled to open in late 2012 before the start of the next rainy season. As a testament to the work from Conco and Robert T. Hill & Associates, the work performed blends into the hillside making it virtually impossible to distinguish between the rocks made by nature and those made by man.

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