June 4, 2018- November 20, 2018
Location: Ferndale, CA
Owner: County of Humboldt
Project Description:The Williams Creek Bridge Replacement project is located in the historic town of Ferndale, CA. For this project, we removed and replaced a bridge that had been in place for over 60 years. A large portion of the population of Ferndale is dairy farmers, this played a critical part in this project as this particular road and bridge are the main access to these farms. To allow both construction and farm activities to occur with the least amount of impact, we installed a railcar bridge and a paved temporary detour adjacent to the bridge site, to allow continuous traffic during most construction activities. Before demolition began, we installed a large headwall with HDPE pipe that ran the length of the channel and installed sheet piles that served as cofferdams on the upstream end of the channel, all water was diverted through this pipe to ensure that no construction activities entered into the waterway. However, during construction, we found that this method was not going to work, due to the pipe being in the way of constructing the abutments and the excavation of the new channel. To mitigate this issue, we installed a bypass diversion that remained in place until the temporary detour was removed. After demolition of the existing bridge, we began construction of the new 60' post-tension strand bridge. To construct, the following activities occurred: structural excavation, excavation in the creek channel, driving (26) HP 14x89 steel piles, bar reinforcing steel, structural concrete for the bridge footings, structural concrete for the remainder of the bridge. After the deck was finished, a Type 80 Barrier Rail was installed. The remainder of the project included: placing approximately 600 tons of Hot Mix Asphalt, installing guardrail, placing survey monuments, and installing final erosion control measures which included 20,000 Sf of hydroseed and over 1,500 LF of biodegradable straw wattles. To view more of this project, visit here.