Fish Passage Site 10103557

Coordinates (dec. deg.): 55.89476°, -133.01965°
Legal Description: C069S081E08
Region: Southeast
Road Name: Coffman Cove Road

Datum: NAD83
Quad Name / ITM: Craig D-4
AWC Stream #:
Stream Name: Unnamed

Elevation:

Site Comments: None

Survey Date: Jun 06, 2017

Survey SEA17-CVR08

Observers: Mark Eisenman, Elizabeth Flory, Kelly Petty

Overall Fish Passage Rating: Red

Tidal: No
Backwatered: No

Step Pools: No
Construction Year:


Site Observations:

  1. Culvert gradient gray

Comments: Riprap downstream with steep drop off - barrier to fish migration. The culvert does not appear to be a barrier to fish passage and is set at close to 1% of the stream gradient, however a large 14 foot rip rap falls created by road prism just downstream from the culvert does appear to be a total barrier. Dolly Varden char caught just downstream of falls

Culvert Measurements

ID: 1 Structure Type: Circular pipe (Structural steel plate) Fish Passage Rating: Gray
 
Length(ft): 67.3
Inlet Type: Mitered
Outlet Type: Mitered
Corrugation Depth(in.): 2.0
Corrugation Width(in.): 6.5
Condition Rating(1-5): 4
Approach Angle: 2.0
Sedimentation At Inlet: Yes
Inlet Substrate: Cobble
Outlet Substrate: Cobble
InletOutlet
Width(ft):13.0 13.0
Height(ft):9.0 8.3
Apron Length(ft):
Water Depth(ft): 0.19
Rustline Height(ft):
Substrate Depth(ft):4.0 4.7
Backwatered?: No
Baffles Present: Yes
Embedded?: Yes
Embedded Depth(ft): 4.0
Outfall Height: 0.0
Outfall Type: At Stream Grade
Constriction Ratio: 2.4
Culvert Gradient: 3.38%
Max Slope:
Max Slope Length:
 

Comments: Gradient of pipe more than 1% of stream gradient, but site has a barrier downstream of culvert caused by road prism rip rap. Baffled.
  Culvert Observations:
  1. Culvert gradient gray

Stream Measurements

Stream SubstratesUpstreamDownstream
Dominant:OrganicBoulder
Subdominant:CobbleGravel
Stream Slope(deg.):4.74
Stream Flow Stage:Medium
Stream Width Type Distance From
Crossing (ft)		 Stream
Width (ft)
Upstream ordinary high water 50.0 5.20
Upstream ordinary high water 100.0 6.00
Upstream ordinary high water 150.0 5.00

Elevations

Locator ID Culvert
Number		 River
Distance (ft)1		 Distance From
Crossing (ft)2		 Relative
Elevation (ft)
Road Elev 108.01
D/S Grade Ctrl (Thalweg) (base of boulder falls) 0.00 80.95
D/S Water Surface Elev 0.00 81.28
D/S Tailcrest or 1st Thalweg (top of boulder falls) 37.00 95.02
D/S Water Surface Elev 37.00 95.35
D/S Water Surface Elev 50.00 95.51
Outlet Invert 50.00 95.32
Outlet Culvert Top 59.00 104.88
Inlet Culvert Top 126.30 107.16
U/S Water Surface Elev 135.30 99.04
Inlet Culvert Invert 135.30 98.85
U/S Grade Ctrl (Thalweg) (first resting) 147.30 98.85
D/S Water Surface Elev 147.30 99.18
U/S Grade Ctrl (Thalweg) (top of log step) 163.30 101.82
U/S Water Surface Elev 163.30 101.99
U/S Grade Ctrl (Thalweg) 239.30 103.16
U/S Water Surface Elev 239.30 103.54

Notes:

  1. River distance is measured continuously throughout the survey reach along the thalweg of the stream.
  2. Measured from each end of the crossing along the thalweg of the stream.

Fish Sampling Efforts

Gear Type: Minnow Trap (A) Trap Duration(h): 2.5
Comments: no fish
 
Gear Type: Minnow Trap (B) Trap Duration(h): 2.5
Comments: two dollys caught

Fish Observations

Species: juvenile Dolly Varden Life History:
Total Fish Observed: 2 Fish Measured: 2 Fork Lengths (mm) Min: 98 Max: 99 Mean: 98
Collected/Observed by Gear Type: Downstream Minnow Trap (2)  

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