Fish Passage Site 20401231

Coordinates (dec. deg.): 61.52496°, -149.52979°
Legal Description: S017N001W31
Region: South Central
Road Name: Surrey Road

Datum: WGS84
Quad Name / ITM: Anchorage C-7
AWC Stream #:
Stream Name: Cottonwood Creek Trib

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-MS030

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

Overall Fish Passage Rating: Green

Tidal: No
Backwatered: No

Step Pools: No
Construction Year: 2007


Site Observations:

  1. None of this type

Comments: Large Sockeye adult spotted upstream. Inlet #1 and 2 have separate streams that converge higher upstream. Outlet only has one combined stream.

Culvert Measurements

ID: 1 Structure Type: Open-bottom arch (Structural steel plate) Fish Passage Rating: Green
 
Length(ft): 50.35
Inlet Type: Projecting
Outlet Type: Projecting
Corrugation Depth(in.): 2.0
Corrugation Width(in.): 6.0
Condition Rating(1-5): 4
Approach Angle: 6.0
Sedimentation At Inlet: Yes
Inlet Substrate: Cobble
Outlet Substrate: Cobble
InletOutlet
Width(ft):13.3 13.0
Height(ft):5.9 5.3
Apron Length(ft):
Water Depth(ft):0.0 0.24
Rustline Height(ft):0.6
Substrate Depth(ft):1.0 0.6
Backwatered?: No
Baffles Present: No
Embedded?: Yes
Embedded Depth(ft): 1.0
Outfall Height: 0.0
Outfall Type: At Stream Grade
Constriction Ratio:
Culvert Gradient: 1.81%
Max Slope:
Max Slope Length:
 

Comments: No constriction ratio calculations due to 2 open bottom pipe arches.
  Culvert Observations:
  1. None of this type
ID: 2 Structure Type: Open-bottom arch (Structural steel plate) Fish Passage Rating: Green
 
Length(ft): 50.42
Inlet Type: Projecting
Outlet Type: Projecting
Corrugation Depth(in.): 2.0
Corrugation Width(in.): 6.0
Condition Rating(1-5): 4
Approach Angle: 6.0
Sedimentation At Inlet: No
Inlet Substrate: Cobble
Outlet Substrate: Cobble
InletOutlet
Width(ft):13.2 13.0
Height(ft):5.8 6.0
Apron Length(ft):
Water Depth(ft):0.0 0.75
Rustline Height(ft):0.4
Substrate Depth(ft):0.8 0.9
Backwatered?: No
Baffles Present: No
Embedded?: Yes
Embedded Depth(ft): 0.9
Outfall Height: 0.0
Outfall Type: At Stream Grade
Constriction Ratio:
Culvert Gradient: 2.08%
Max Slope:
Max Slope Length:
  Culvert Observations:
  1. None of this type

Stream Measurements

Stream SubstratesUpstreamDownstream
Dominant:CobbleCobble
Subdominant:SandSand
Stream Slope(deg.):2.19
Stream Flow Stage:High
Stream Width Type Distance From
Crossing (ft)		 Stream
Width (ft)
Downstream ordinary high water 62.0 37.00
Downstream ordinary high water 120.0 49.20
Downstream ordinary high water 200.0 59.00

Elevations

Locator ID Culvert
Number		 River
Distance (ft)1		 Distance From
Crossing (ft)2		 Relative
Elevation (ft)
Road Elev 102.01
D/S Thalweg 0.00 91.00
D/S Water Surface Elev 0.00 91.97
D/S Thalweg 79.00 93.30
D/S Water Surface Elev 79.00 94.16
Outlet Invert 2 119.00 94.33
Outlet Invert 1 119.00 94.66
D/S Water Surface Elev 1 119.00 94.90
D/S Water Surface Elev 2 119.00 95.08
Outlet Culvert Top 2 119.00 99.93
Outlet Culvert Top 1 119.00 100.08
Inlet Culvert Top 2 169.42 100.98
Inlet Culvert Top 1 169.42 100.99
Inlet Culvert Invert 2 169.42 95.54
Inlet Culvert Invert 1 169.42 95.92
U/S Water Surface Elev 1 169.42 96.09
U/S Water Surface Elev 2 169.42 96.52
U/S Water Surface Elev (Pool WS) 1 180.42 96.76
U/S Thalweg (Pool Depth) 1 180.42 95.77
U/S Water Surface Elev 1 208.42 96.98
U/S Thalweg 1 208.42 96.26
U/S Thalweg 2 241.42 96.65
U/S Water Surface Elev 2 241.42 97.06
U/S Thalweg 1 258.42 96.78
U/S Water Surface Elev 1 258.42 97.58
U/S Thalweg 2 263.42 97.64
U/S Water Surface Elev 2 263.42 98.32
U/S Water Surface Elev 1 274.42 98.25
U/S Thalweg 1 274.42 97.23
U/S Thalweg 314.42 99.08
U/S Water Surface Elev 314.42 99.35
U/S Thalweg 376.42 99.42
U/S Water Surface Elev 376.42 100.22

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