Fish Passage Site 20401344

Coordinates (dec. deg.): 61.71796°, -149.12068°
Legal Description: S019N002E20
Region: South Central
Road Name: Murphy Road

Datum: NAD83
Quad Name / ITM: Anchorage C-6
AWC Stream #: 247-50-10260-2019-3120
Stream Name: Wasilla Creek tributary

Elevation:

Site Comments: The outlet area consists of three step pools created by piled cobble/boulders with one pool at the outlet.

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-MUR01

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

Overall Fish Passage Rating: Green

Tidal: No
Backwatered: No

Step Pools: Yes
Construction Year: 2008


Site Observations:

  1. None of this type

Comments: Step pools in pipe. Post-replacement survey of MSCS1WA040; Upstream gradient = 4.2%. Someone has built a dam at upper most step pool.

Culvert Measurements

ID: 1 Structure Type: Circular pipe (Corrugated steel) Fish Passage Rating: Green
 
Length(ft): 45.1
Inlet Type: Projecting
Outlet Type: Projecting
Corrugation Depth(in.): 1.0
Corrugation Width(in.): 3.0
Condition Rating(1-5): 4
Approach Angle: 0.0
Sedimentation At Inlet: No
Inlet Substrate: Cobble
Outlet Substrate: Gravel
InletOutlet
Width(ft):6.0 6.0
Height(ft):3.7 4.3
Apron Length(ft):
Water Depth(ft): 0.27
Rustline Height(ft):
Substrate Depth(ft):2.3 1.8
Backwatered?: No
Baffles Present: No
Embedded?: Yes
Embedded Depth(ft): 1.8
Outfall Height: 0.0
Outfall Type: At Stream Grade
Constriction Ratio: 0.9
Culvert Gradient: 3.80%
Max Slope:
Max Slope Length:
  Culvert Observations:
  1. None of this type

Stream Measurements

Stream SubstratesUpstreamDownstream
Dominant:GravelGravel
Subdominant:GravelGravel
Stream Slope(deg.):4.2
Stream Flow Stage:Medium
Stream Width Type Distance From
Crossing (ft)		 Stream
Width (ft)
Upstream ordinary high water 62.0 7.00
Upstream ordinary high water 115.0 7.00
Upstream ordinary high water 155.0 6.00

Elevations

Locator ID Culvert
Number		 River
Distance (ft)1		 Distance From
Crossing (ft)2		 Relative
Elevation (ft)
U/S Water Surface Elev (water surface used for stream grad) 1 0.00 102.72
U/S Water Surface Elev (Stream gradient) 1 115.00 97.85
U/S Grade Ctrl (Thalweg) (grade point at top of cobble step pool) 1 121.00 97.43
U/S Water Surface Elev 1 121.00 97.75
U/S Water Surface Elev 1 124.00 97.36
U/S Thalweg (upst max pool) 1 124.00 96.65
U/S Grade Ctrl (Thalweg) (grade pt at top of boulder step) 1 128.00 97.06
U/S Water Surface Elev 1 128.00 97.34
U/S Water Surface Elev (inlet water surface) 1 135.00 96.76
Inlet Culvert Invert (invert on substrate) 1 135.00 96.34
Top of Pipe Inlet 1 135.00 100.00
Road Elev 1 155.00 101.23
Outlet Culvert Top 1 180.50 98.65
Outlet Invert (invert on substrate) 1 180.50 94.61
D/S Water Surface Elev (outlet water surface) 1 180.50 94.88
Outlet Pool Water Elev 1 191.50 94.85
Max Pool Depth (max pool depth) 1 191.50 94.23
D/S Tailcrest or 1st Thalweg (top of 1st rock riffle forming the outlet step pool area) 1 193.50 94.54
D/S Water Surface Elev 1 193.50 94.80
D/S Water Surface Elev 1 204.50 93.10
D/S Grade Ctrl (Thalweg) (top of step pool below ATV crossing) 1 204.50 92.57
D/S Water Surface Elev 1 210.50 92.73
D/S Grade Ctrl (Thalweg) (top of outlet of 3rd step pool with boulders) 1 210.50 92.33
D/S Thalweg (max pool before three upst step pools below outlet) 1 232.50 91.24
D/S Water Surface Elev 1 232.50 91.98

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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