Fish Passage Site 20401307

Coordinates (dec. deg.): 61.61382°, -149.29070°
Legal Description: S018N001E33
Region: South Central
Road Name: Bogard Road

Datum: NAD83
Quad Name / ITM: Anchorage C-7
AWC Stream #: 247-50-10300
Stream Name: Cottonwood Creek

Elevation:

Site Comments: Old ATV Xing upstrm-some use; Active ATV Xing downstream-goes up and over culverts

Multiple surveys have been conducted at this site — click on the drop down
arrow to the right of the survey date below to choose a different report for this site.

Survey MSCS1-CT159

Observers: Edward Weiss, Joe Conner

Overall Fish Passage Rating: Red

Tidal: No
Backwatered: No

Step Pools:
Construction Year:


Site Observations:

  1. Constriction ratio red

Comments: Old ATV Xing upstrm-some use;Active ATV Xing downstream-goes up and over culverts; Caving/erosion/sediment input; boulders at culvert inlets may impede fish passage; boulder at outlet (east culvert);Tailcrest mainly debris filled

Culvert Measurements

ID: 1 Structure Type: Closed-bottom arch (Strutural Metal Plate) Fish Passage Rating: Red
 
Length(ft): 126.0
Inlet Type: Projecting
Outlet Type:
Corrugation Depth(in.): 1.0
Corrugation Width(in.): 3.0
Condition Rating(1-5): 3
Approach Angle:
Sedimentation At Inlet:
Inlet Substrate: Gravel
Outlet Substrate: Gravel
InletOutlet
Width(ft):6.0 6.0
Height(ft):5.9 5.0
Apron Length(ft):
Water Depth(ft):1.0 1.4
Rustline Height(ft):
Substrate Depth(ft):0.1 1.0
Backwatered?: No
Baffles Present: No
Embedded?: No
Outfall Height:
Outfall Type: At Stream Grade
Constriction Ratio: 0.29
Culvert Gradient: 0.26%
Max Slope:
Max Slope Length:
  Culvert Observations:
  1. Constriction ratio red
ID: 2 Structure Type: Closed-bottom arch (Strutural Metal Plate) Fish Passage Rating: Red
 
Length(ft): 126.0
Inlet Type: Projecting
Outlet Type:
Corrugation Depth(in.): 1.0
Corrugation Width(in.): 3.0
Condition Rating(1-5):
Approach Angle:
Sedimentation At Inlet:
Inlet Substrate: Gravel
Outlet Substrate: Gravel
InletOutlet
Width(ft):7.0 7.0
Height(ft):6.4 6.7
Apron Length(ft):
Water Depth(ft):1.0 1.15
Rustline Height(ft):
Substrate Depth(ft):0.6 0.3
Backwatered?: No
Baffles Present: No
Embedded?: No
Outfall Height:
Outfall Type: At Stream Grade
Constriction Ratio: 0.29
Culvert Gradient: 0.87%
Max Slope:
Max Slope Length:
  Culvert Observations:
  1. Constriction ratio red
  2. Culvert gradient gray

Stream Measurements

Stream SubstratesUpstreamDownstream
Dominant:
Subdominant:
Stream Slope(deg.):
Stream Flow Stage:
Stream Width Type Distance From
Crossing (ft)		 Stream
Width (ft)
Downstream ordinary high water 50.0 34.50
Downstream ordinary high water 93.0 36.60
Upstream ordinary high water 50.0 37.00
Upstream ordinary high water 100.0 17.00

Elevations

Locator ID Culvert
Number		 River
Distance (ft)1		 Distance From
Crossing (ft)2		 Relative
Elevation (ft)
D/S Thalweg 82.21
D/S Tailcrest or 1st Thalweg 83.52
Outlet Culvert Top 1 88.27
Outlet Culvert Top 2 89.24
Inlet Culvert Top 1 89.84
D/S Thalweg 0.00 93.0 81.97
Outlet Thalweg 2 93.00 0.0 82.81
Outlet Invert 2 93.00 0.0 82.90
Outlet Thalweg 1 93.00 0.0 82.93
Outlet Invert 1 93.00 0.0 83.39
Road Elev 156.00 99.22
Road Elev 156.00 100.88
Inlet Culvert Invert 2 213.00 -6.0 84.00
Inlet Culvert Invert 1 220.20 1.2 83.72
Inlet Thalweg (Correct the inst Num from 3 to 1) 2 223.00 4.0 73.47
Inlet Thalweg 1 223.00 4.0 84.62
U/S Thalweg 2 227.50 8.5 84.50
U/S Thalweg 235.00 16.0 84.23
U/S Thalweg (Base of gravel plume) 264.00 45.0 84.61
U/S Thalweg 269.00 50.0 85.35
U/S Thalweg 319.00 100.0 85.32

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: Visual Observation, Ground (C)

Fish Observations

Species: adult coho salmon Life History: Anadromous (Suspected Spawning)
Total Fish Observed: Fish Measured: Fork Lengths (mm) Min: Max: Mean:
Collected/Observed by Gear Type: Upstream Visual Observation, Ground ()  
Comments: Adult coho observed upstream and downstream of culvert

Photos

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