DESCRIPTION
The problem is 2 fish passage barrier culverts on Camp Creek on separate road
crossings on Schafer Boom Road southeast of Montesano, Washington. These barriers
are:
Site 1: WDFW Site ID 127S0362. 46.9801/-123.56473. 0.16 miles south of Schafer
Boom/Simmons Rd. junction. 33% passable. Rip rap is present at both the culvert
inlet and outlet Rip rap at the outlet creates large scour pool. The barrier consists of
a round corrugated steel pipe, 3' in diameter, 30' long, not countersunk, with a slope
of 2.2%. Slope is reason for barrier determination. The stream has a 20' bankfull
width. The site is at stream mile 0.42.
Site 2: WDFW Site ID 127S0361. 46.98121/-123.56489. 0.10 miles south of Schafer
Boom/Simmons Rd. junction. The barrier culvert is a round corrugated steel pipe 3'
in diameter and 36' long. High velocities create a 67% passable barrier. The site is at
stream mile 0.55.
This restoration and design combo project corrected one fish passage barrier on worksite 1, opening .13 miles of high quality habitat for Chinook, coho and chum salmon, steelhead and cutthroat trout, and produce construction ready designs for another culvert replacement along the same road on worksite 2. This work is on Camp Creek in Grays Harbor County, WA.
At worksite 1 the work completed included the removal of 33% passable fish passage barrier, consisting of a round corrugated steel pipe, 3' in diameter, 30' long, not countersunk, with a slope of 2.2%. It was replaced with a box culvert to provide all life forms and stages of aquatic species with access to critical upstream habitat. Native trees were planted in the areas directly adjacent of the culvert to restore the disturbed areas. The site was monitored after high flows over the first winter after construction and features were functioning as designed.
For worksite 2 construction will be completed under a separate funding opportunity. The correction was designed to remove existing 67% passable round corrugated steel pipe. Site surveys, geotechnical investigations, wetland delineation, final project designs, design report, construction cost estimate and bid book were completed. All necessary permits were applied for and issued. The correction with future funds will result in installation of a pre-cast concrete bridge that will provide all life forms and stages of aquatic species with access to critical upstream habitat.
Final project costs varied from the project cost estimates for the following reasons:
Worksite 1 construction cost was lower than estimated because of low bids from the hired construction contractor.
Worksite 2 design cost was higher than estimated for several reasons. The new County Engineer required that the design address potential earthquake loads. This necessitated hiring a contractor to complete geotechnical analysis as well as having the bridge footings designed by the specialized engineering firm. The US Army Corps of Enigneers required a wetland delineation, which was also above and beyond the cost estimate.