Fish Passage Site 20401303

Coordinates (dec. deg.): 61.55406°, -149.48825°
Legal Description: S017N001W20
Region: South Central
Road Name: Edlund

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

Elevation:

Site Comments: None

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 MSB23-MS016

Project Supervisor: Michael Mazzacavallo, Alaska Department of Fish and Game — Anchorage, AK
Observers: Michael Mazzacavallo, Kat Leavitt, Beth Evers

Overall Fish Passage Rating: Green

Tidal:
Backwatered: No

Step Pools:
Construction Year: 2020


Site Observations:

  1. Constriction ratio gray

Comments: Replaced in 2020. Adult sockeye spotted. Upstream of culvert the channel is split, and downstream is a slow moving pool.

Culvert Measurements

ID: 1 Structure Type: Box culvert (Structural aluminum plate) Fish Passage Rating: Green
 
Length(ft): 54.19
Inlet Type: Headwall
Outlet Type: Headwall
Corrugation Depth(in.): 3.0
Corrugation Width(in.): 9.0
Condition Rating(1-5): 5
Approach Angle: 10.0
Sedimentation At Inlet: No
Inlet Substrate: Cobble
Outlet Substrate: Cobble
InletOutlet
Width(ft):16.0 16.0
Height(ft):5.6 5.6
Apron Length(ft):
Water Depth(ft): 1.33
Rustline Height(ft):
Substrate Depth(ft):2.7 2.3
Backwatered?: No
Baffles Present: No
Embedded?: Yes
Embedded Depth(ft): 2.3
Outfall Height: 0.0
Outfall Type: At Stream Grade
Constriction Ratio: 0.68
Culvert Gradient: 0.33%
Max Slope:
Max Slope Length:
  Culvert Observations:
  1. Constriction ratio gray

Stream Measurements

Stream SubstratesUpstreamDownstream
Dominant:OrganicCobble
Subdominant:SandGravel
Stream Slope(deg.):0.38
Stream Flow Stage:Medium
Stream Width Type Distance From
Crossing (ft)		 Stream
Width (ft)
Downstream ordinary high water 140.0 24.00
Downstream ordinary high water 170.0 24.00
Downstream ordinary high water 200.0 22.00

Elevations

Locator ID Culvert
Number		 River
Distance (ft)1		 Distance From
Crossing (ft)2		 Relative
Elevation (ft)
Road Elev 100.60
U/S Thalweg 0.00 93.02
U/S Water Surface Elev 0.00 95.11
U/S Water Surface Elev 27.00 94.99
U/S Thalweg 27.00 93.61
U/S Thalweg 78.00 93.77
U/S Water Surface Elev 78.00 94.87
U/S Water Surface Elev 109.00 94.50
Inlet Culvert Top 109.00 98.77
Inlet Culvert Invert 109.00 93.23
Outlet Culvert Top 163.19 98.59
Outlet Invert 163.19 92.97
D/S Water Surface Elev 163.19 94.30
D/S Thalweg 254.19 92.39
D/S Water Surface Elev 254.19 94.08
D/S Water Surface Elev 263.19 94.09
D/S Thalweg 263.19 91.82

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

No fish sampling occurred during this survey.

Fish Observations

No fish observations occurred during this survey.

Questions or comments about this report can be directed to dfg.dsf.webmaster@alaska.gov