The Middle Fork Nooksack River Fish Passage project is the #1 Recovery Action of the Water Resources Inventory Area (WRIA) 1
Salmon Recovery Plan, and resulted in the greatest Nooksack Chinook salmon population increase of any other single restoration action modeled. Following Elwha Dam removal, the Puget Sound Chinook Recovery Plan cites the Middle Fork project as an example of a major action to restore access to historic Chinook salmon spawning and rearing habitat in Puget Sound. The Diversion Dam is the only built fish passage barrier in the Middle Fork Nooksack River.
This project will reestablish access to as many as 16 miles of spawning and rearing habitat for the Endangered Species Act (ESA) listed spring Chinook salmon, Puget Sound Steelhead and Bull Trout while maintaining municipal water supply. The project is also poised to contribute to
Southern Resident Killer Whale (SRKW) recovery through increased prey availability. In addition to species benefits, the project provides cultural, economic and recreational benefits as detailed below.
The project is expected to result in the following specific benefits:
North/Middle Fork Nooksack Spring Chinook salmon will regain access to an estimated 14 miles of upstream habitat, much of it relatively pristine, resulting in a population abundance increase of 31%, productivity increase of 12%, and diversity index increase of 48%. 
Coastal-Puget Sound Bull Trout will regain approximately 16 miles of upstream habitat. Restoring population connectivity at the dam is a priority action identified in the
Bull Trout Recovery Plan.
Puget Sound Steelhead will regain access to an estimated 45% of their historic habitat in the Middle Fork watershed.
Species and instream flow protection in the project vicinity will increase as a result of a newly installed compliant fish screen, and formalizing operating procedures.
Upstream habitat contains coldwater thermal refugia  that produces long-term benefits to species under future climate change scenarios.
Removal of the existing dam will result in more natural channel conditions, providing benefit to recreational kayakers navigating this section of the Middle Fork.
The construction project will provide the equivalent economic impact of creating 224 direct and indirect jobs.
Based on Ecosystem Diagnosis and Treatment [EDT] analysis.
Areas with colder water that may increase fish resiliency to higher water temperatures and lower baseflows under climate change scenarios.