Fish Passage Site 20501222

Coordinates (dec. deg.): 61.49357°, -149.66008°
Legal Description: S016N002W08
Region: South Central
Road Name: Rubacaba Road

Datum: WGS84
Quad Name / ITM: Anchorage B-8
AWC Stream #:
Stream Name: O'Brien 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-RBC01

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

Overall Fish Passage Rating: Red

Tidal: No
Backwatered: No

Step Pools: No
Construction Year:


Site Observations:

  1. Outfall height gray
  2. Culvert gradient red

Comments: Pipe has rust line at 0.7 ft on one side, 1.9 ft on other (has been rotated?). ***Updated site photos added from 6-8-15 site visit.

Culvert Measurements

ID: 1 Structure Type: Circular pipe (Corrugated steel) Fish Passage Rating: Red
 
Length(ft): 47.7
Inlet Type: Projecting
Outlet Type: Projecting
Corrugation Depth(in.): 0.5
Corrugation Width(in.): 2.67
Condition Rating(1-5): 2
Approach Angle: 17.0
Sedimentation At Inlet: Yes
Inlet Substrate: None
Outlet Substrate: None
InletOutlet
Width(ft):3.0 3.0
Height(ft):2.9 3.0
Apron Length(ft):
Water Depth(ft): 0.24
Rustline Height(ft):
Substrate Depth(ft):0.0 0.0
Backwatered?: No
Baffles Present: No
Embedded?: No
Outfall Height: 0.21
Outfall Type: Free Fall In To Pool
Constriction Ratio: 0.75
Culvert Gradient: 1.55%
Max Slope:
Max Slope Length:
  Culvert Observations:
  1. Outfall height gray
  2. Culvert gradient red
ID: 2 Structure Type: Circular pipe (Corrugated steel) Fish Passage Rating: Red
 
Length(ft): 48.4
Inlet Type: Projecting
Outlet Type: Projecting
Corrugation Depth(in.): 0.5
Corrugation Width(in.): 2.67
Condition Rating(1-5): 2
Approach Angle: 17.0
Sedimentation At Inlet: Yes
Inlet Substrate: None
Outlet Substrate: None
InletOutlet
Width(ft):3.0 3.0
Height(ft):3.0 3.1
Apron Length(ft):
Water Depth(ft): 0.37
Rustline Height(ft):0.6
Substrate Depth(ft):0.0 0.0
Backwatered?: No
Baffles Present: No
Embedded?: No
Outfall Height: 0.0
Outfall Type: At Stream Grade
Constriction Ratio: 0.75
Culvert Gradient: 1.92%
Max Slope:
Max Slope Length:
  Culvert Observations:
  1. Culvert gradient red

Stream Measurements

Stream SubstratesUpstreamDownstream
Dominant:Silt/ClaySilt/Clay
Subdominant:Silt/ClayCobble
Stream Slope(deg.):
Stream Flow Stage:Medium
Stream Width Type Distance From
Crossing (ft)		 Stream
Width (ft)
Downstream ordinary high water 60.0 5.50
Downstream ordinary high water 85.0 6.00
Downstream ordinary high water 110.0 5.50

Elevations

Locator ID Culvert
Number		 River
Distance (ft)1		 Distance From
Crossing (ft)2		 Relative
Elevation (ft)
D/S Water Surface Elev (d/s WS - d/s channel is nearly flat & featureless past 12' d/s) 0.00 36.0 95.86
D/S Water Surface Elev (d/s WS - pipe 2 has riffle out to 12') 24.00 12.0 95.87
D/S Thalweg (toe of riffle out of pipe 2) 2 24.00 12.0 95.09
D/S Tailcrest or 1st Thalweg (TWC pipe 1 only) 1 31.50 4.5 96.13
D/S Water Surface Elev (WS @ TWC) 1 31.50 4.5 96.37
Outlet Pool Water Elev 2 36.00 96.32
Outlet Invert 1 36.00 0.0 96.34
Outlet Pool Water Elev (outlet pool pipe 1 only) 1 36.00 96.37
Outlet Invert 2 36.00 0.0 95.95
D/S Thalweg 1 36.00 0.0 96.12
Road Elev 60.00 104.02
Inlet Culvert Invert 2 84.00 0.0 96.88
Inlet Culvert Invert 1 84.00 0.0 97.08
U/S Headwater 2 84.00 97.31
U/S Headwater 1 84.00 97.33
U/S Water Surface Elev 2 86.00 2.0 97.33
U/S Water Surface Elev 1 86.00 2.0 97.34
U/S Grade Ctrl (Thalweg) (pool u/s slight GP) 1 86.00 2.0 97.09
U/S Grade Ctrl (Thalweg) 2 86.00 2.0 96.88

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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