Fish Passage Site 20401267

Coordinates (dec. deg.): 61.63185°, -149.24325°
Legal Description: S018N001E22
Region: South Central
Road Name: Settlement Road

Datum: WGS84
Quad Name / ITM: Anchorage C-6
AWC Stream #: 247-50-10300-2054
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 MSB09-SET01

Project Supervisor: Gillian O'Doherty, ADFG
Observers: Heidi Zimmer, Ben Histand

Overall Fish Passage Rating: Green

Tidal: No
Backwatered: Yes

Step Pools: No
Construction Year: 2009


Site Observations:

  1. Culvert is poorly aligned

Comments: Post-replacement survey of MSCS1CT110; TWC>inverts=BW, slightly; u/s grade = 0.13%; Stream substrate flat in pipe.

Culvert Measurements

ID: 1 Structure Type: Open-bottom arch (Structural steel plate) Fish Passage Rating: Green
 
Length(ft): 64.4
Inlet Type: Projecting
Outlet Type: Projecting
Corrugation Depth(in.): 2.0
Corrugation Width(in.): 6.0
Condition Rating(1-5): 4
Approach Angle: 41.0
Sedimentation At Inlet: No
Inlet Substrate: Sand
Outlet Substrate: Gravel
InletOutlet
Width(ft):9.7 9.6
Height(ft):4.9 3.8
Apron Length(ft):
Water Depth(ft): 0.54
Rustline Height(ft):1.3
Substrate Depth(ft):
Backwatered?: Yes
Baffles Present: No
Embedded?: Yes
Outfall Height: 0.0
Outfall Type: At Stream Grade
Constriction Ratio: 1.11
Culvert Gradient: 0.89%
Max Slope:
Max Slope Length:
  Culvert Observations:
  1. Culvert is poorly aligned

Stream Measurements

Stream SubstratesUpstreamDownstream
Dominant:SandSilt/Clay
Subdominant:Silt/ClayCobble
Stream Slope(deg.):0.13
Stream Flow Stage:Medium
Stream Width Type Distance From
Crossing (ft)		 Stream
Width (ft)
Upstream ordinary high water 50.0 8.50
Upstream ordinary high water 90.0 9.00
Upstream ordinary high water 125.0 8.50

Elevations

Locator ID Culvert
Number		 River
Distance (ft)1		 Distance From
Crossing (ft)2		 Relative
Elevation (ft)
Outlet Pool Water Elev 1 96.17
U/S Headwater 1 96.18
D/S Water Surface Elev (d/s ws) 1 0.00 50.0 95.87
D/S Water Surface Elev (ws @ TWC) 1 43.00 7.0 96.13
D/S Tailcrest or 1st Thalweg 1 43.00 7.0 95.64
Outlet Invert (thalweg on substrate) 1 50.00 0.0 95.63
Road Elev 82.20 103.05
Inlet Culvert Invert (thalweg on substrate) 1 114.40 0.0 95.10
U/S Grade Ctrl (Thalweg) (soft substrate) 1 139.40 25.0 95.14
U/S Water Surface Elev 1 139.40 25.0 96.19
U/S Water Surface Elev (u/s ws) 1 226.40 112.0 96.30

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.

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