South Anker Creek
Migration Barrier Removal Project
Completed in 2002, the South Anker Creek Project was ranked as the 9th highest priority project in Humboldt County under the 5C Migration Barrier Inventory (RTA). The culvert shown above not only served as a complete barrier to all life stages of salmonids, but was also extremely undersized. In 1999, the barrier located downstream was removed by Humboldt County. These two projects have opened access to approximately 1.4 miles of salmonid habitat on South Anker Creek.
This project is an example of a type of grade control solution. A total grade differential of 6 feet was attenuated with this installation. There are a total of five grade control weirs external to the culvert with a 5% weir-induced grade through the culvert. The design is a further hybrid in that it combines a concrete base with a metal box top.
Humboldt County was the first 5C County to adopt a grading ordinance. The County has adopted the Roads Maintenance Manual and has also initiated the development of an updated general plan based on watershed planning.
To date, Humboldt County has removed 22 migration barriers at stream crossings
on County Roads, restoring access to approximately 35 miles of anadromous
habitat. Many of these projects have been completed in-house through the Humboldt
County Department of Public Works. For a more in-depth look at what's happening
with migration barriers in the area, click the links below:
Humboldt County Migration Barrier Inventory Report
Humboldt County Migration Barrier Culvert Catalog
Partially Completed in 2004