Humboldt Bay Trail North

foot bridge next to train tracks
Humboldt Bay Trail North
Contract Amount: $4,671,833.00      Final Amount: $4,743,926.57
Project Duration: May 2017- November 2017

Owners: City of Arcata
Location: Arcata Marsh, Arcata, CA
Project Description:
For the Humboldt Bay Trail North project, we constructed a 2.7 mile paved ADA accessible bike and pedestrian trail through wetlands. This trail included five premanufactured bridges, 14 cast-in-place concrete structures (for the pre-manufactured bridges), RSP, and installing storm drain pipe. The water measures during construction included driving sheet pile and installing aqua dams to isolate the work area from the Humboldt Bay. Work was performed around the tide schedule to minimize turbid water. Turbidity monitoring and testing was completed per permit requirements. To complete this project, we implemented many rehabilitation and habitat enhancement techniques. Such as precision grading and installing sheetpiling/cofferdams to contain turbidity.
The grading for this project took place in the middle of marsh sensitive areas, resulting in the grading being precise and accurate within the irregular terrain, to not allow any material to impede on the native trees, vegetation, and existing wetland. Excavation in saturated soils happened within 4 separate water ways, Jacoby Creek, South Jacoby Creek, Gannon Slough and the Humboldt Bay. After excavation was completed, we used a variety of rock material along the excavated banks to protect the habitat within the water ways, as well as protect the banks from erosion. Above the placed rock material, biodegrable coir mat netting was placed to stabilize the slope. Placed under this matting were deschampsia cuttings collected from other parts of the site. This enhanced and promoted the habitat to return the area back to its natural state after performing the needed excavation. This project required working in small areas to avoid encroaching on sensitive habitat. Exclusion fencing was placed strategically throughout the project to shield the sensitive areas. Protected plants were “flagged” to alert workers of protected species. Various permanent boulders were placed along the path to shield sensitive habitat from any possible disturbance. Want to learn more about this project? Please visit here.