Fish Passage Site 20401278

Coordinates (dec. deg.): 61.58256°, -149.39583°
Legal Description: S017N001W11
Region: South Central
Road Name: Palmer Wasilla Highway

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

Elevation:

Site Comments: Outlet channel at Cottonwood Lake which connects to a large flat slough area.

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-CT127

Observers: Doug Hill, Joe Conner, Michael Wiedmer

Overall Fish Passage Rating: Green

Tidal: No
Backwatered: No

Step Pools:
Construction Year:


Comments: None

Culvert Measurements

ID: 1 Structure Type: Circular pipe (Corrugated steel) Fish Passage Rating: Green
 
Length(ft): 82.0
Inlet Type: Mitered
Outlet Type: Mitered
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):7.5 7.5
Height(ft):4.5 5.9
Apron Length(ft):
Water Depth(ft):1.5 1.8
Rustline Height(ft):
Substrate Depth(ft):
Backwatered?:
Baffles Present: No
Embedded?:
Outfall Height: 0.0
Outfall Type: At Stream Grade
Constriction Ratio:
Culvert Gradient: 0.28%
Max Slope:
Max Slope Length:
  Culvert Observations:
  1. None of this type

Stream Measurements

Stream SubstratesUpstreamDownstream
Dominant:GravelGravel
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 1 91.23
Outlet Culvert Top 1 91.46
D/S Thalweg 0.00 45.1 86.49
D/S Tailcrest or 1st Thalweg 30.90 14.2 86.20
Outlet Invert 1 45.10 0.0 85.46
Outlet Thalweg 1 45.10 0.0 85.46
Road Elev 86.10 92.86
Road Elev 86.10 95.05
Inlet Culvert Invert 1 127.10 0.0 86.66
Inlet Thalweg 1 127.10 0.0 86.66

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 (B) Trap Duration(h): 1
 
Gear Type: Visual Observation, Ground (C)

Fish Observations

Species: juvenile/adult stickleback-unspecified Life History: Resident
Total Fish Observed: 1 Fish Measured: Fork Lengths (mm) Min: Max: Mean:
Collected/Observed by Gear Type: Downstream Minnow Trap (1)  
 
Species: adult coho salmon Life History: Anadromous
Total Fish Observed: 15 Fish Measured: Fork Lengths (mm) Min: Max: Mean:
Collected/Observed by Gear Type: Upstream Visual Observation, Ground (15)  
Comments: Adult coho present above, below, and moving thru the culvert
 
Species: juvenile coho salmon Life History: Anadromous
Total Fish Observed: 16 Fish Measured: 8 Fork Lengths (mm) Min: 59 Max: 93 Mean: 78
Collected/Observed by Gear Type: Downstream Minnow Trap (16)  
 
Species: juvenile rainbow trout Life History: Resident
Total Fish Observed: 4 Fish Measured: 2 Fork Lengths (mm) Min: 11 Max: 115 Mean: 63
Collected/Observed by Gear Type: Downstream Minnow Trap (4)  

Photos

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