Fish Passage Site 20401291

Coordinates (dec. deg.): 61.52220°, -149.52682°
Legal Description: S017N001W31
Region: South Central
Road Name: Surrey Road

Datum: NAD83
Quad Name / ITM: Anchorage C-7
AWC Stream #: 247-50-10300-2012
Stream Name: Cottonwood Slough

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-SUR01

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

Overall Fish Passage Rating: Green

Tidal: No
Backwatered: No

Step Pools: No
Construction Year: 2007


Site Observations:

  1. Shallow fill; inadequate roadfill volume above culvert

Comments: Post-Replacement survey of MSCS1CT140;.

Culvert Measurements

ID: 1 Structure Type: Circular pipe (Corrugated steel) Fish Passage Rating: Green
 
Length(ft): 50.2
Inlet Type: Projecting
Outlet Type: Projecting
Corrugation Depth(in.): 1.0
Corrugation Width(in.): 3.0
Condition Rating(1-5): 5
Approach Angle: 7.0
Sedimentation At Inlet: No
Inlet Substrate: Gravel
Outlet Substrate: Gravel
InletOutlet
Width(ft):7.0 7.0
Height(ft):4.8 4.4
Apron Length(ft):
Water Depth(ft): 0.5
Rustline Height(ft):
Substrate Depth(ft):2.2 2.6
Backwatered?: No
Baffles Present: No
Embedded?: Yes
Embedded Depth(ft): 1.4
Outfall Height: 0.0
Outfall Type: At Stream Grade
Constriction Ratio: 1.43
Culvert Gradient: 0.74%
Max Slope:
Max Slope Length:
 

Comments: Downstream stream gradient = 0.78%.
  Culvert Observations:
  1. Shallow fill; inadequate roadfill volume above culvert

Stream Measurements

Stream SubstratesUpstreamDownstream
Dominant:Silt/ClaySilt/Clay
Subdominant:Silt/ClaySilt/Clay
Stream Slope(deg.):0.78
Stream Flow Stage:Medium
Stream Width Type Distance From
Crossing (ft)		 Stream
Width (ft)
Downstream ordinary high water 35.0 5.50
Downstream ordinary high water 70.0 4.50
Downstream ordinary high water 110.0 4.50

Elevations

Locator ID Culvert
Number		 River
Distance (ft)1		 Distance From
Crossing (ft)2		 Relative
Elevation (ft)
Road Elev 1 100.95
D/S Grade Ctrl (Thalweg) 1 0.00 111.0 94.12
D/S Water Surface Elev (ws @ gp) 1 0.00 111.0 94.49
D/S Tailcrest or 1st Thalweg 1 98.50 12.5 94.89
D/S Water Surface Elev (ws @ TWC) 1 98.50 12.5 95.07
D/S Water Surface Elev 1 107.50 3.5 95.09
D/S Thalweg (high pt) 1 107.50 3.5 94.77
Outlet Pool Water Elev 1 111.00 95.09
Outlet Invert 1 111.00 0.0 94.59
Inlet Culvert Invert 1 161.20 0.0 95.15
U/S Headwater 1 161.20 95.46
U/S Grade Ctrl (Thalweg) (TC of pool/wetland u/s (constructed?)) 1 169.20 8.0 96.03
U/S Water Surface Elev (ws @ gp) 1 169.20 8.0 96.18

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 (A) Trap Duration(h): 1.0
Comments: 50ft u/s
 
Gear Type: Minnow Trap (B) Trap Duration(h): 1.0
Comments: 80ft d/s

Fish Observations

Species: juvenile coho salmon Life History: Anadromous
Total Fish Observed: 42 Fish Measured: 42 Fork Lengths (mm) Min: 42 Max: 113 Mean: 73
Collected/Observed by Gear Type: Downstream Minnow Trap (31)  Upstream Minnow Trap (11)  
 
Species: stickleback-unspecified Life History: Resident
Total Fish Observed: 8 Fish Measured: 0 Fork Lengths (mm) Min: Max: Mean:
Collected/Observed by Gear Type: Downstream Minnow Trap (8)  

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