High Creek bridge before construction
High Creek before construction
The project is currently under construction and will be completed by fall 2018.
In 1922, Whatcom County was deeded a drainage right-of-way for the westerly 3,000 feet of High Creek to address flooding damage to adjacent agricultural land and regular closures of the county road servicing the Kendall area. This section of the creek was then placed in a dredged linear channel. The county retained the drainage right-of-way when the road was deeded over to the state to become State Route 542.
Over time, sediment has accumulated in this section of low gradient stream channel, causing the streambed to become higher than the adjacent ground. The elevated streambed increases the risk of flooding. During a 1990 flood event, High Creek overtopped its bank, and flooding damaged nearby homes and businesses. This section of stream channel is also a fish passage barrier to migrating salmon and steelhead where it is shallow and spreads out in an adjoining pasture before entering Kendall Creek. The county evaluated alternatives and developed a sediment management plan as part of an agreement with impacted landowners. This project implements that management plan.
This project consists of the following key pieces. First, sediment will be removed from the channel to lower the streambed. Second, the berms lining the channel will be shaped to provide a consistent level of flood protection along the full length of the project area. Third, two sediment traps will be installed to capture the annual flow of sediment into the project area. These traps will be easily maintained and will allow for removal of excess sediment that would otherwise raise the channel bed and reduce flood conveyance. Fourth, a clear connection of High Creek to Kendall Creek will be re-established and habitat structures installed in the confluence area to provide fish passage and improve instream habitat. Finally, all disturbed areas will be replanted with native trees and shrubs to protect water quality and improve habitat over the long term.
Watershed Science and Engineering (WSE) prepared the Sediment Management Plan (see below), performed the hydraulic modeling, and oversaw the engineering design. Pacific Survey and Engineering (PSE) did the engineering design. Whatcom Conservation District developed a detailed planting plan.
Gary F. Goodall, River & Flood Engineer (construction related questions)
John N. Thompson, L.E.G., Senior Salmon Recovery Planner (project purpose and management related questions)