Fish Passage Site 20100630

Coordinates (dec. deg.): 60.54337°, -145.73997°
Legal Description: C015S003W27
Region: South Central
Road Name: Power Creek Road

Datum: NAD83
Quad Name / ITM: Cordova C-5
AWC Stream #:
Stream Name: Eyak Lake Tributary

Elevation:

Site Comments: Just above Nirvana Park.

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-23

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

Overall Fish Passage Rating: Red

Tidal: No
Backwatered: No

Step Pools: No
Construction Year:


Site Observations:

  1. Culvert gradient red
  2. Constriction ratio gray
  3. Culvert is poorly aligned
  4. Compound gradient in pipe

Comments: Replacement survey done by CRWP in 2015. Manipulated channel upstream from culvert. Upstream hillside channel used for constriction ratio about 0.1 miles upstream. There is a 2' overflow pipe set 1 foot higher than main culvert invert. Large culvert in outlet photos does not connect to the stream.

Culvert Measurements

ID: 1 Structure Type: Circular pipe (Corrugated steel) Fish Passage Rating: Red
 
Length(ft): 52.8
Inlet Type: Headwall
Outlet Type: Headwall
Corrugation Depth(in.): 0.75
Corrugation Width(in.): 2.0
Condition Rating(1-5): 4
Approach Angle: 90.0
Sedimentation At Inlet: No
Inlet Substrate: None
Outlet Substrate: None
InletOutlet
Width(ft):3.0 3.0
Height(ft):3.0 3.0
Apron Length(ft):
Water Depth(ft): 0.37
Rustline Height(ft):0.55
Substrate Depth(ft):0.0 0.0
Backwatered?: No
Baffles Present: No
Embedded?: No
Outfall Height: 0.21
Outfall Type: Cascade Over Rip-Rap
Constriction Ratio: 0.52
Culvert Gradient: 5.04%
Max Slope:
Max Slope Length:
 

Comments: Constriction ratio is based on only one measurement. Stream slope was calculated with a clinometer.
  Culvert Observations:
  1. Culvert gradient red
  2. Constriction ratio gray
  3. Culvert is poorly aligned
  4. Compound gradient in pipe
ID: 2 Structure Type: Circular pipe (Corrugated steel) Fish Passage Rating:
 
Length(ft): 52.8
Inlet Type: Headwall
Outlet Type: Headwall
Corrugation Depth(in.):
Corrugation Width(in.):
Condition Rating(1-5): 4
Approach Angle:
Sedimentation At Inlet:
Inlet Substrate: None
Outlet Substrate: None
InletOutlet
Width(ft):2.0 2.0
Height(ft):2.0 2.0
Apron Length(ft):
Water Depth(ft): 0.0
Rustline Height(ft):
Substrate Depth(ft):0.0 0.0
Backwatered?:
Baffles Present:
Embedded?:
Outfall Height:
Outfall Type: Overflow Pipe
Constriction Ratio:
Culvert Gradient:
Max Slope:
Max Slope Length:
 

Comments: Overflow pipe site invert set 1 foot higher than main culvert.

Stream Measurements

Stream SubstratesUpstreamDownstream
Dominant:GravelCobble
Subdominant:SandGravel
Stream Slope(deg.):3
Stream Flow Stage:Medium
Stream Width Type Distance From
Crossing (ft)		 Stream
Width (ft)
Downstream ordinary high water 35.0 15.50
Upstream ordinary high water 30.0 3.80
Upstream ordinary high water 500.0 5.70

Elevations

Locator ID Culvert
Number		 River
Distance (ft)1		 Distance From
Crossing (ft)2		 Relative
Elevation (ft)
Road Elev 102.34
D/S Grade Ctrl (Thalweg) 0.00 92.78
D/S Water Surface Elev 0.00 93.38
D/S Grade Ctrl (Thalweg) 22.70 93.35
D/S Water Surface Elev 22.70 93.68
D/S Water Surface Elev 40.90 93.80
D/S Grade Ctrl (Thalweg) 40.90 93.37
D/S Tailcrest or 1st Thalweg 51.10 93.83
D/S Water Surface Elev 51.10 94.14
D/S Water Surface Elev 54.40 94.23
Max Pool Depth (Cascades with small pool) 54.40 93.38
Outlet Invert 1 59.80 94.07
D/S Water Surface Elev 59.80 94.44
Outlet Invert (Overflow pipe, dry) 2 59.80 95.03
Outlet Culvert Top 2 59.80 97.03
Outlet Culvert Top 1 59.80 97.07
U/S Water Surface Elev 1 112.60 97.21
Inlet Culvert Invert 1 112.60 96.73
Inlet Culvert Invert (dry) 2 112.60 97.66
U/S Thalweg (Inlet pool max depth) 117.80 96.22
U/S Water Surface Elev 117.80 94.23
U/S Grade Ctrl (Thalweg) 131.00 96.07
U/S Water Surface Elev 131.00 97.25
U/S Grade Ctrl (Thalweg) (above foot bridge) 155.00 97.56
U/S Water Surface Elev 155.00 97.76

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)
 
Gear Type: Minnow Trap (B)
 
Gear Type: Minnow Trap (C)
Comments: No fish caught.

Fish Observations

Species: juvenile coho salmon Life History: Anadromous
Total Fish Observed: 2 Fish Measured: 2 Fork Lengths (mm) Min: 31 Max: 35 Mean: 33
Collected/Observed by Gear Type: Upstream Minnow Trap (2)  
 
Species: juvenile Dolly Varden Life History:
Total Fish Observed: 1 Fish Measured: 1 Fork Lengths (mm) Min: 60 Max: 60 Mean: 60
Collected/Observed by Gear Type: Upstream Minnow Trap (1)  

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