Fish Passage Site 10103546

Coordinates (dec. deg.): 55.62292°, -132.97083°
Legal Description: C072S081E15
Region: Southeast
Road Name: Big Salt Lake Road

Datum: NAD83
Quad Name / ITM: Craig C-3
AWC Stream #: 103-60-10330
Stream Name: Unnamed

Elevation:

Site Comments: None

Survey Date: Jul 26, 2017

Survey SEA17-BSL30

Observers: Elizabeth Flory, Kelly Petty

Overall Fish Passage Rating: Red

Tidal: No
Backwatered: No

Step Pools: No
Construction Year:


Site Observations:

  1. Compound gradient in pipe
  2. Culvert gradient red

Comments: Steep bouldery cascades upstream, 4ft high boulder step at 400ft upstream. Downstream boulder step cascades and nice deep pools with large woody debris. 10.7% gradient upstream and gets steeper. Observed tiny dolly varden fry 20ft downstream from outlet. Current gradient through pipe on substrate is 8.75% and water surface gradient through culvert is 9.72% which is close to the measured downstream gradient of 8.33% and the measured upstream gradient of 10.70, however culvert was set at 3.32% calculated from top of pipe elevations. Had culvert still been embedded it would have rated as gray for not being embedded to within 1% of stream gradient.

Culvert Measurements

ID: 1 Structure Type: Circular pipe (Structural steel plate) Fish Passage Rating: Gray
 
Length(ft): 63.0
Inlet Type: Mitered
Outlet Type: Mitered
Corrugation Depth(in.): 2.0
Corrugation Width(in.): 6.0
Condition Rating(1-5): 4
Approach Angle: 3.0
Sedimentation At Inlet: Yes
Inlet Substrate: Boulder
Outlet Substrate: Cobble
InletOutlet
Width(ft):15.4 15.5
Height(ft):11.5 13.8
Apron Length(ft):
Water Depth(ft): 0.85
Rustline Height(ft):2.5
Substrate Depth(ft):3.9 1.7
Backwatered?: No
Baffles Present: No
Embedded?: No
Outfall Height: 0.0
Outfall Type: At Stream Grade
Constriction Ratio: 1.21
Culvert Gradient: 3.32%
Max Slope:
Max Slope Length:
 

Comments: Inlet is mitred with concrete headwall. Pipe slope includes 2ft and 1ft high boulder steps. Too dark in pipe to survey gradient breaks. Spray paint lines inside culvert look to mark level or substrate that was installed in culvert. Most of the substrate from the lower half has been scoured away and culvert is no longer embedded. Large boulders in middle of culvert create 1-2 ft cascades and may now be a partial barrier to juvenile movement.
  Culvert Observations:
  1. Compound gradient in pipe

Stream Measurements

Stream SubstratesUpstreamDownstream
Dominant:BoulderBoulder
Subdominant:CobbleCobble
Stream Slope(deg.):8.33
Stream Flow Stage:Medium
Stream Width Type Distance From
Crossing (ft)		 Stream
Width (ft)
Upstream ordinary high water 60.0 11.00
Upstream ordinary high water 80.0 14.00
Upstream ordinary high water 100.0 13.00

Elevations

Locator ID Culvert
Number		 River
Distance (ft)1		 Distance From
Crossing (ft)2		 Relative
Elevation (ft)
Road Elev 116.55
D/S Grade Ctrl (Thalweg) 0.00 90.07
D/S Water Surface Elev 0.00 90.57
D/S Grade Ctrl (Thalweg) (top of boulder step) 23.00 92.69
D/S Water Surface Elev 23.00 93.07
D/S Grade Ctrl (Thalweg) (top of boulder step) 74.00 96.65
D/S Water Surface Elev 74.00 97.18
D/S Water Surface Elev 86.00 98.42
D/S Tailcrest or 1st Thalweg (boulders) 86.00 97.26
Max Pool Depth 94.00 97.25
D/S Water Surface Elev 94.00 98.40
D/S Water Surface Elev 118.00 98.88
Outlet Invert (on substrate) 118.00 98.03
Outlet Culvert Top 130.00 113.10
Inlet Culvert Top 193.00 115.19
U/S Water Surface Elev 205.00 106.49
Inlet Culvert Invert (estimated end of mitre, on substrate) 205.00 105.69
U/S Grade Ctrl (Thalweg) 211.00 105.82
U/S Water Surface Elev 211.00 106.41
U/S Grade Ctrl (Thalweg) 255.00 110.01
U/S Water Surface Elev 255.00 110.70
U/S Grade Ctrl (Thalweg) 311.00 117.00
U/S Water Surface Elev 311.00 117.69
U/S Water Surface Elev (steeper riffle cascade above this point) 321.00 118.18
U/S Grade Ctrl (Thalweg) 321.00 117.06

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): 2.7
Comments: 100ft upstream, no fish
 
Gear Type: Minnow Trap (B) Trap Duration(h): 2.0
Comments: 300ft downstream, no fish
 
Gear Type: Visual Observation, Ground (C)
Comments: Observed Dolly Varden fry about 20 feet downstream

Fish Observations

Species: Dolly Varden Life History:
Total Fish Observed: 5 Fish Measured: Fork Lengths (mm) Min: Max: Mean:
Collected/Observed by Gear Type: Upstream Minnow Trap (5)  

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