South Fork Bridge

Work consisted of constructing a new bridge along the north side of the South Fork Tuolumne River in Tuolumne County, California. Existing concrete piers and foundations were removed, and new concrete retaining walls and stone masonry walls were constructed. The road was also rebuilt by backfilling and 1,400 feet were paved with concrete.

Other work included installing storm drains and inlets, excavating, shoring and removing rock, boulders and compacting for road embankment, and replacing the stairs at the siphon site. This project was both environmentally sensitive and was to help on the erosion due to the river.

Mitchell Engineering’s access was via a narrow service road by which all materials, including the partially prefabricated steel truss’ and heavy equipment needed to carefully navigate.

Owner: San Francisco Public Utilities Commission (Hetch Hetchy)