Fish Passage Site 20100710

Coordinates (dec. deg.): 61.59142°, -145.22214°
Legal Description: C003S001E21
Region: South Central
Road Name: Richardson Highway

Datum: NAD83
Quad Name / ITM: Valdez C-4
AWC Stream #:
Stream Name: Little Tonsina Tributary

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 UPDATE-RICH28

Project Supervisor: Gillian O'Doherty, ADFG
Observers: Andrew Kastning

Overall Fish Passage Rating: Red

Tidal: No
Backwatered: No

Step Pools: No
Construction Year:


Site Observations:

  1. Culvert gradient red
  2. Road bank erosion

Comments: This assessment was conducted by the Copper River Watershed Project. An old perched culvert is about 400 feet upstream on an ATV access road.

Culvert Measurements

ID: 1 Structure Type: Circular pipe (Corrugated steel) Fish Passage Rating: Red
 
Length(ft): 80.8
Inlet Type: Projecting
Outlet Type: Projecting
Corrugation Depth(in.): 0.5
Corrugation Width(in.): 2.75
Condition Rating(1-5): 3
Approach Angle: 15.0
Sedimentation At Inlet: Yes
Inlet Substrate: Cobble
Outlet Substrate: Gravel
InletOutlet
Width(ft):5.15 4.9
Height(ft):4.21 2.42
Apron Length(ft):
Water Depth(ft): 0.59
Rustline Height(ft):0.85
Substrate Depth(ft):0.46 2.2
Backwatered?: No
Baffles Present: No
Embedded?: No
Outfall Height: 0.0
Outfall Type: At Stream Grade
Constriction Ratio: 0.84
Culvert Gradient: 4.45%
Max Slope:
Max Slope Length:
  Culvert Observations:
  1. Culvert gradient red
  2. Road bank erosion

Stream Measurements

Stream SubstratesUpstreamDownstream
Dominant:CobbleCobble
Subdominant:GravelGravel
Stream Slope(deg.):3.5
Stream Flow Stage:Low
Stream Width Type Distance From
Crossing (ft)		 Stream
Width (ft)
Downstream ordinary high water 8.60
Downstream ordinary high water 5.60
Downstream ordinary high water 5.70
Upstream ordinary high water 5.50
Upstream ordinary high water 7.00
Upstream ordinary high water 5.80
Upstream ordinary high water 6.10

Elevations

Locator ID Culvert
Number		 River
Distance (ft)1		 Distance From
Crossing (ft)2		 Relative
Elevation (ft)
Road Elev 106.04
D/S Grade Ctrl (Thalweg) 0.00 92.63
D/S Water Surface Elev 0.00 92.95
D/S Tailcrest or 1st Thalweg 95.00 94.10
D/S Water Surface Elev 95.00 94.52
Outlet Pool Water Elev 103.00 94.57
Max Pool Depth 103.00 93.91
Outlet Invert 107.00 93.98
D/S Water Surface Elev 107.00 94.57
Outlet Culvert Top 107.00 96.40
U/S Water Surface Elev 188.00 96.24
Inlet Culvert Top 188.00 100.00
Inlet Culvert Invert 188.00 95.79
U/S Grade Ctrl (Thalweg) 195.00 96.17
U/S Water Surface Elev 195.00 96.79
U/S Grade Ctrl (Thalweg) 221.00 97.47
U/S Water Surface Elev 221.00 97.77
U/S Grade Ctrl (Thalweg) 334.00 101.27
U/S Water Surface Elev 334.00 101.78

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

Gear Type: Minnow Trap (A) Trap Duration(h): 18.0
Comments: 3 traps set upstream
 
Gear Type: Minnow Trap (B) Trap Duration(h): 18.0
Comments: 3 traps set downstream

Fish Observations

Species: juvenile Chinook salmon Life History: Anadromous
Total Fish Observed: 1 Fish Measured: 1 Fork Lengths (mm) Min: 80 Max: 80 Mean: 80
Collected/Observed by Gear Type: Downstream Minnow Trap (1)  
 
Species: juvenile coho salmon Life History: Anadromous
Total Fish Observed: 1 Fish Measured: 1 Fork Lengths (mm) Min: 75 Max: 75 Mean: 75
Collected/Observed by Gear Type: Downstream Minnow Trap (1)  
 
Species: Dolly Varden Life History: Unknown
Total Fish Observed: 9 Fish Measured: 9 Fork Lengths (mm) Min: 65 Max: 220 Mean: 116
Collected/Observed by Gear Type: Downstream Minnow Trap (4)  Upstream Minnow Trap (5)  

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