Fish Passage Site 20100771

Coordinates (dec. deg.): 62.64306°, -144.53079°
Legal Description: C010N005E17
Region: South Central
Road Name: Tok Cut-Off

Datum: NAD83
Quad Name / ITM: Gulkana C-2
AWC Stream #: 212-20-10080-2583
Stream Name: Unnamed


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.


Project Supervisor: Gillian O'Doherty, ADFG
Observers: Kirsti Jurica

Overall Fish Passage Rating: Gray

Tidal: No
Backwatered: No

Step Pools: No
Construction Year:

Site Observations:

  1. Outfall height gray
  2. Inlet perch
  3. Culvert is poorly aligned

Comments: Survey and data collected by CRWP. All photos CRWP. Culvert is aligned with upstream channel, but old scour pool exists downstream due to an 80 degree turn, most likely caused from 2006 flood.

Culvert Measurements

ID: 1 Structure Type: Circular pipe (Structural steel plate) Fish Passage Rating: Gray
Length(ft): 126.7
Inlet Type: Mitered
Outlet Type: Mitered
Corrugation Depth(in.): 2.25
Corrugation Width(in.): 6.0
Condition Rating(1-5): 4
Approach Angle: 20.0
Sedimentation At Inlet: Yes
Inlet Substrate: Cobble
Outlet Substrate: None
Width(ft):9.8 9.4
Height(ft):9.08 10.18
Apron Length(ft):
Water Depth(ft): 0.6
Rustline Height(ft):0.85
Substrate Depth(ft):0.41 0.0
Backwatered?: No
Baffles Present: No
Embedded?: No
Outfall Height: 0.17
Outfall Type: Hydraulic Jump
Constriction Ratio: 1.16
Culvert Gradient: 0.64%
Max Slope:
Max Slope Length:

Comments: Substrate gradient though culvert is 1.2 and takes into account cascades on the miters.

  Culvert Observations:
  1. Outfall height gray
  2. Inlet perch
  3. Culvert is poorly aligned

Stream Measurements

Stream SubstratesUpstreamDownstream
Stream Slope(deg.):2
Stream Flow Stage:Medium
Stream Width Type Distance From
Crossing (ft)
Width (ft)
Downstream ordinary high water 11.50
Downstream ordinary high water 12.70
Downstream ordinary high water 9.20
Upstream ordinary high water 8.30
Upstream ordinary high water 7.80
Upstream ordinary high water 9.10


Locator ID Culvert
Distance (ft)1
Distance From
Crossing (ft)2
Elevation (ft)
Outlet Culvert Top 96.41
Road Elev 101.35
Inlet Culvert Top 97.22
D/S Grade Ctrl (Thalweg) 0.00 85.51
D/S Water Surface Elev 0.00 85.92
D/S Tailcrest or 1st Thalweg 75.00 86.08
D/S Water Surface Elev 75.00 86.65
Max Pool Depth 84.00 84.31
Outlet Pool Water Elev 84.00 86.66
D/S Thalweg 100.50 85.67
D/S Water Surface Elev 100.50 86.79
Outlet Invert 103.00 86.23
D/S Water Surface Elev 103.00 86.83
Inlet Culvert Invert 229.70 88.14
U/S Water Surface Elev 229.70 88.79
U/S Grade Ctrl (Thalweg) 255.70 89.49
U/S Water Surface Elev 255.70 90.14
U/S Grade Ctrl (Thalweg) 325.70 89.50
U/S Water Surface Elev 325.70 90.60


  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): 15.0
Comments: 3 traps set upstream
Gear Type: Minnow Trap (B) Trap Duration(h): 15.0
Comments: 3 traps set downstream

Fish Observations

Species: juvenile Chinook salmon Life History: Anadromous
Total Fish Observed: 2 Fish Measured: 2 Fork Lengths (mm) Min: 65 Max: 71 Mean: 68
Collected/Observed by Gear Type: Downstream Minnow Trap (2)  
Species: Dolly Varden Life History: Unknown
Total Fish Observed: 1 Fish Measured: 1 Fork Lengths (mm) Min: 120 Max: 120 Mean: 120
Collected/Observed by Gear Type: Upstream Minnow Trap (1)  

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