Fish Passage Site 20401304

Coordinates (dec. deg.): 61.56313°, -149.45046°
Legal Description: S017N001W16
Region: South Central
Road Name: Fern

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

Elevation:

Site Comments: Ponded above & below (aquatic & wetland)

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-CT155

Observers: Edward Weiss, Joe Conner, Nathan Pannkuk

Overall Fish Passage Rating: Gray

Tidal: No
Backwatered: No

Step Pools:
Construction Year:


Comments: Ponded above and below Ponded above & below (aquatic & wetland) - bankful 109' wide; center & right culverts 1/2 full of substrate; F/CG/S in channel;S & Silt in area of aquatics;channel thru aquatic veg;concrete headwall

Culvert Measurements

ID: 1 Structure Type: Open-bottom arch (Strutural Metal Plate) Fish Passage Rating: Gray
 
Length(ft): 48.0
Inlet Type: Projecting
Outlet Type:
Corrugation Depth(in.): 2.0
Corrugation Width(in.): 6.0
Condition Rating(1-5):
Approach Angle:
Sedimentation At Inlet:
Inlet Substrate: Gravel
Outlet Substrate: Gravel
InletOutlet
Width(ft):8.0 8.0
Height(ft):4.2 4.7
Apron Length(ft):
Water Depth(ft):1.0 1.55
Rustline Height(ft):
Substrate Depth(ft):
Backwatered?:
Baffles Present: No
Embedded?: No
Outfall Height:
Outfall Type:
Constriction Ratio:
Culvert Gradient: 1.25%
Max Slope:
Max Slope Length:
  Culvert Observations:
  1. None of this type
ID: 2 Structure Type: Open-bottom arch (Strutural Metal Plate) Fish Passage Rating: Gray
 
Length(ft): 40.3
Inlet Type: Projecting
Outlet Type:
Corrugation Depth(in.): 0.5
Corrugation Width(in.): 2.67
Condition Rating(1-5):
Approach Angle:
Sedimentation At Inlet:
Inlet Substrate: Gravel
Outlet Substrate: Gravel
InletOutlet
Width(ft):5.0 5.0
Height(ft):1.8 2.0
Apron Length(ft):
Water Depth(ft):0.6 0.8
Rustline Height(ft):
Substrate Depth(ft):
Backwatered?:
Baffles Present: No
Embedded?: No
Outfall Height:
Outfall Type:
Constriction Ratio:
Culvert Gradient: 0.62%
Max Slope:
Max Slope Length:
  Culvert Observations:
  1. None of this type
ID: 3 Structure Type: Open-bottom arch (Strutural Metal Plate) Fish Passage Rating: Gray
 
Length(ft): 40.3
Inlet Type: Projecting
Outlet Type:
Corrugation Depth(in.): 0.5
Corrugation Width(in.): 2.67
Condition Rating(1-5):
Approach Angle:
Sedimentation At Inlet:
Inlet Substrate: Gravel
Outlet Substrate: Gravel
InletOutlet
Width(ft):5.0 5.0
Height(ft):2.0 2.2
Apron Length(ft):
Water Depth(ft):0.9 1.0
Rustline Height(ft):
Substrate Depth(ft):
Backwatered?:
Baffles Present: No
Embedded?: No
Outfall Height:
Outfall Type:
Constriction Ratio:
Culvert Gradient: 0.99%
Max Slope:
Max Slope Length:
  Culvert Observations:
  1. None of this type

Stream Measurements

Stream SubstratesUpstreamDownstream
Dominant:
Subdominant:
Stream Slope(deg.):
Stream Flow Stage:Medium

No stream width data available.

Elevations

Locator ID Culvert
Number		 River
Distance (ft)1		 Distance From
Crossing (ft)2		 Relative
Elevation (ft)
Inlet Culvert Top 3 91.20
Outlet Culvert Top 2 91.25
Outlet Culvert Top 3 91.28
Inlet Culvert Top 2 91.33
Outlet Culvert Top 1 93.13
Inlet Culvert Top 1 93.29
D/S Thalweg 0.00 44.0 88.07
Outlet Invert 1 44.00 0.0 88.44
Outlet Thalweg 1 44.00 0.0 88.44
Outlet Invert 3 44.00 0.0 88.93
Outlet Thalweg 3 44.00 0.0 88.93
Outlet Invert 2 44.00 0.0 89.17
Outlet Thalweg 2 44.00 0.0 89.17
Road Elev 65.00 96.02
Road Elev 65.00 96.18
Inlet Culvert Invert 1 86.00 0.0 89.04
Inlet Thalweg 1 86.00 0.0 89.04
Inlet Culvert Invert 3 86.00 0.0 89.33
Inlet Thalweg 3 86.00 0.0 89.33
Inlet Culvert Invert 2 86.00 0.0 89.42
Inlet Thalweg 2 86.00 0.0 89.42
U/S Thalweg 1 91.00 5.0 88.73
U/S Thalweg 3 91.00 5.0 88.84
U/S Thalweg 2 91.00 5.0 89.14
U/S Thalweg 111.00 25.0 88.41
U/S Thalweg 136.00 50.0 88.09
U/S Thalweg (Upstream thalweg) 167.00 81.0 88.20
U/S Thalweg 176.00 90.0 88.68

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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