Prioritization of and Rehabilitation Designs for Fish Migration Impediments in Fraser River Tributaries West of Brunette River
The primary goals of the project were to identify man-made impediments or barriers (i.e., culvert
or flood box) to salmon migration in selected tributaries to the Fraser River west of Brunette River
and to recommend rehabilitation alternatives for each high priority culvert or flood box structure.
Fish distributions, existing habitat characteristics and condition, length of habitat upstream of
floodbox and importance of habitat for salmon were described for each of the 13 man-made fish
passage impediments. Five high priority fish migration impediments were investigated in greater
detail. They included: Cohilukthan Slough, Crescent Slough, 96th St Canal, Fleetwood Creek,
and McLean Creek. Operational regimes for several of the sites were evaluated for potential fish
passage capability during adult coho migration, coho smolt immigration and Chinook fry
immigration / egress. The recommendations ranged from the straight forward (i.e., maintenance
of the structure or replacing the flapgate) to the more complex (i.e., reconfiguration or
reorientation of the structure, replacing all or parts of the structure with more fish-friendly
technology, etc.). For each of the five priority sites, constraints to modifying the physical structure
or floodbox operation were determined and conceptual engineering designs and preliminary cost
estimates were provided for potential replacement with a self-regulating tidal gate.