WRECO is on the project team to repair multiple storm-damaged sections of roadway along Spanish Ranch Road in Santa Cruz County. The roadway and slope failures occurred after a series of storm events in February 2017 caused heavy erosion under and around the roadway. Construction of retaining walls, slop protection, and roadway repairs have been completed at Post Mile (PM) 0.20 and 0.37, and construction is pending at the intersection of Highland Way and Spanish Ranch Road. Challenges on this project included designing around steep, hilly terrain, working within a limited roadway width, and the need to keep at least one lane open during construction. WRECO provided geotechnical investigations and Geotechnical Engineering Studies, including providing repair recommendations, as a subconsultant to Dokken Engineering.
The most recently completed construction at PM 0.20 repairs approximately 30 feet (ft) of damaged roadway and includes construction of a soldier pile wall and drainage improvements. The construction at PM 0.37 repairs approximately 70 ft of damaged roadway and also includes construction of a soldier pile wall and drainage improvements. WRECO recommended soldier pile walls at PM 0.20 and 0.37 because they could be constructed from the existing roadway, are self-shoring, require little excavation, and typically will allow for the roadway to be partially opened during construction.
At the intersection of Spanish Ranch Road and Highland Way, the pending construction will repair the slope failure, damaged culvert, and an approximately 15- to 20-ft section of damaged roadway. The repair will include replacement of the damaged culvert and construction of a soil nail wall, asphalt concrete (AC) dike, AC pavement, metal beam guard rail, and erosion control and revegetation.