Fish Passage Site 10302170

Coordinates (dec. deg.): 58.33908°, -134.54660°
Legal Description: C041S066E01
Region: Southeast
Road Name: North Douglas Highway

Datum: NAD83
Quad Name / ITM: Juneau B-2
AWC Stream #:
Stream Name: Johnson Creek

Elevation:

Site Comments: None

Survey Date: Jun 17, 2011

Survey SEA11-NDH04

Project Supervisor: Gillian O'Doherty, Alaska Department of Fish and Game — Anchorage, AK
Observers: Mark Eisenman, Jason Olds

Overall Fish Passage Rating: Red

Tidal: No
Backwatered: No

Step Pools: No
Construction Year:


Site Observations:

  1. Constriction ratio red
  2. Culvert gradient red
  3. Outfall height gray

Comments: No traps set as stream was already in AWC. Vertical oval pipe. Gradient measurement taken 43 feet downstream from the invert in inside of pipe because a complete sighting through the pipe or over was not possible, pipe length/gradient was too long/steep to shoot level through the pipe and road fill grade was too steep and overgrown. Outfall was nearly a hydraulic jump at .11 feet however lower water levels could create a more significant freefall to pool.

Culvert Measurements

ID: 1 Structure Type: Oval (Corrugated steel) Fish Passage Rating: Red
 
Length(ft): 143.7
Inlet Type: Projecting
Outlet Type: Projecting
Corrugation Depth(in.): 2.0
Corrugation Width(in.): 6.0
Condition Rating(1-5): 4
Approach Angle: 14.0
Sedimentation At Inlet: No
Inlet Substrate: None
Outlet Substrate: None
InletOutlet
Width(ft):6.3 6.3
Height(ft):7.0 7.0
Apron Length(ft):
Water Depth(ft): 0.2
Rustline Height(ft):1.8
Substrate Depth(ft):0.0 0.0
Backwatered?: No
Baffles Present: No
Embedded?: No
Outfall Height: 0.09
Outfall Type: Free Fall In To Pool
Constriction Ratio: 0.41
Culvert Gradient: 6.30%
Max Slope:
Max Slope Length:
  Culvert Observations:
  1. Constriction ratio red
  2. Culvert gradient red
  3. Outfall height gray

Stream Measurements

Stream SubstratesUpstreamDownstream
Dominant:GravelGravel
Subdominant:CobbleCobble
Stream Slope(deg.):
Stream Flow Stage:Medium
Stream Width Type Distance From
Crossing (ft)		 Stream
Width (ft)
Upstream ordinary high water 38.0 14.30
Upstream ordinary high water 83.0 20.50
Upstream ordinary high water 155.0 11.80

Elevations

Locator ID Culvert
Number		 River
Distance (ft)1		 Distance From
Crossing (ft)2		 Relative
Elevation (ft)
D/S Grade Ctrl (Thalweg) 0.00 97.98
D/S Water Surface Elev 0.00 98.37
D/S Tailcrest or 1st Thalweg 33.00 98.74
D/S Water Surface Elev (Tailwater control) 33.00 99.09
Outlet Pool Water Elev 50.00 99.14
Max Pool Depth 50.00 96.22
D/S Water Surface Elev (Invert out) 61.00 99.23
Outlet Invert (Invert out, on metal) 61.00 99.03
D/S Grade Ctrl (Thalweg) (Substrate below invert out) 61.00 98.28
Misc. (Inside pipe, 43 feet from invert out, measurement for gradient estimation) 104.00 101.76

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: None (A)
Comments: No traps set no fish observed.

Fish Observations

No fish observations occurred during this survey.

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