Fish Passage Site 20401335

Coordinates (dec. deg.): 61.63222°, -149.20032°
Legal Description: S018N001E24
Region: South Central
Road Name: private drive

Datum: NAD83
Quad Name / ITM: Anchorage C-6
AWC Stream #: 247-50-10260-2019
Stream Name: Wasilla 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 MSB11-PRD01

Project Supervisor: Gillian O'Doherty, Alaska Department of Fish and Game — Anchorage, AK
Observers: John Greuey, Abraham Gioffre

Overall Fish Passage Rating: Gray

Tidal: No
Backwatered: No

Step Pools: No
Construction Year:


Site Observations:

  1. Constriction ratio gray
  2. Sediment accumulation
  3. Structural Problem

Comments: Three parallel culverts with homemade headwall constructed of corrugated metal roofing with stakes filled with gravel behind it to make new road surface over three pipes. Outlets of pipes contained piled up cobble creating a flow restriction. Water level through all pipes was near equal. Long profile starts upstream. The constriction ratio calculation for multiple circular pipes was used even though the three pipes were open bottom arch pipes or circular pipes which acted as an embedded structure. Pipes had 100% bedload a

Culvert Measurements

ID: 1 Structure Type: Open-bottom arch (Corrugated steel) Fish Passage Rating: Gray
 
Length(ft): 20.0
Inlet Type: Headwall
Outlet Type: Headwall
Corrugation Depth(in.): 0.75
Corrugation Width(in.): 2.5
Condition Rating(1-5): 3
Approach Angle: 20.0
Sedimentation At Inlet: Yes
Inlet Substrate: Gravel
Outlet Substrate: Gravel
InletOutlet
Width(ft):4.2 4.8
Height(ft):1.9 2.0
Apron Length(ft):0.0 0.0
Water Depth(ft): 0.4
Rustline Height(ft):1.9
Substrate Depth(ft):
Backwatered?: No
Baffles Present: No
Embedded?: Yes
Outfall Height: 0.0
Outfall Type: At Stream Grade
Constriction Ratio: 0.58
Culvert Gradient: 0.00%
Max Slope:
Max Slope Length:
  Culvert Observations:
  1. Constriction ratio gray
  2. Sediment accumulation
  3. Structural Problem
ID: 2 Structure Type: Open-bottom arch (Corrugated steel) Fish Passage Rating: Gray
 
Length(ft): 20.0
Inlet Type: Headwall
Outlet Type: Headwall
Corrugation Depth(in.): 0.75
Corrugation Width(in.): 2.5
Condition Rating(1-5): 3
Approach Angle: 20.0
Sedimentation At Inlet: Yes
Inlet Substrate: Gravel
Outlet Substrate: Gravel
InletOutlet
Width(ft):3.9 4.6
Height(ft):2.5 2.3
Apron Length(ft):0.0 0.0
Water Depth(ft): 1.46
Rustline Height(ft):2.5
Substrate Depth(ft):
Backwatered?: Yes
Baffles Present: No
Embedded?:
Outfall Height: 0.0
Outfall Type: At Stream Grade
Constriction Ratio: 0.58
Culvert Gradient: 0.00%
Max Slope:
Max Slope Length:
  Culvert Observations:
  1. Constriction ratio gray
  2. Sediment accumulation
  3. Structural Problem
ID: 3 Structure Type: Open-bottom arch (Corrugated steel) Fish Passage Rating: Gray
 
Length(ft): 20.0
Inlet Type: Headwall
Outlet Type: Headwall
Corrugation Depth(in.): 0.75
Corrugation Width(in.): 2.5
Condition Rating(1-5): 3
Approach Angle: 20.0
Sedimentation At Inlet: Yes
Inlet Substrate: Gravel
Outlet Substrate: Gravel
InletOutlet
Width(ft):4.7 5.1
Height(ft):2.2 2.1
Apron Length(ft):
Water Depth(ft): 0.66
Rustline Height(ft):2.2
Substrate Depth(ft):
Backwatered?: Yes
Baffles Present: No
Embedded?:
Outfall Height: 0.0
Outfall Type: At Stream Grade
Constriction Ratio: 0.58
Culvert Gradient: 0.00%
Max Slope:
Max Slope Length:
  Culvert Observations:
  1. Constriction ratio gray
  2. Sediment accumulation
  3. Structural Problem

Stream Measurements

Stream SubstratesUpstreamDownstream
Dominant:GravelGravel
Subdominant:CobbleCobble
Stream Slope(deg.):0.25
Stream Flow Stage:Medium
Stream Width Type Distance From
Crossing (ft)		 Stream
Width (ft)
Upstream ordinary high water 157.0 12.50
Upstream ordinary high water 200.0 12.30
Upstream ordinary high water 230.0 13.00

Elevations

Locator ID Culvert
Number		 River
Distance (ft)1		 Distance From
Crossing (ft)2		 Relative
Elevation (ft)
U/S Grade Ctrl (Thalweg) 0.00 94.68
U/S Water Surface Elev 0.00 95.26
U/S Grade Ctrl (Thalweg) 38.00 94.14
U/S Water Surface Elev 38.00 95.14
U/S Water Surface Elev 65.00 95.10
U/S Thalweg (Thalweg point on pool) 65.00 93.52
Inlet Culvert Invert (Left side of diagram) 3 90.00 93.58
Inlet Culvert Invert (Right side of diagram) 1 90.00 93.31
Inlet Culvert Invert 2 90.00 93.49
U/S Water Surface Elev (Water surface at inlet pipe 3) 3 90.00 94.92
U/S Water Surface Elev (Water surface at inlet pipe 1) 1 90.00 94.95
U/S Water Surface Elev (Water surface at inlet pipe 2) 2 90.00 94.96
Road Elev 100.00 98.59
Outlet Invert 3 110.00 94.33
Outlet Invert 1 110.00 94.56
D/S Water Surface Elev (Water surface at outlet pipe 1) 1 110.00 94.96
D/S Water Surface Elev (Water surface at outlet pipe 2) 2 110.00 94.96
D/S Water Surface Elev (Water surface at outlet pipe 3) 3 110.00 94.99
Outlet Invert 2 110.00 93.50

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