Fish Passage Site 10302158

Coordinates (dec. deg.): 58.33170°, -134.49957°
Legal Description: C041S067E08
Region: Southeast
Road Name: North Douglas Highway

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

Elevation:

Site Comments: None

Survey Date: Jun 18, 2011

Survey SEA11-NDH05

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

Overall Fish Passage Rating: Gray

Tidal: Yes
Backwatered: No

Step Pools: No
Construction Year:


Site Observations:

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

Comments: No traps were set as stream is already in AWC. This culvert appears to be tidally influenced by observations of its relative location to the Gastenau Channel as well as riparian vegetation and a rust line on the exterior of the pipe suggesting that at higher tide events, fish could easily enter the culvert. Next to Era Helicopter. Approximate 4 inch salmonid was observed upstream from the culvert.

Culvert Measurements

ID: 1 Structure Type: Circular pipe (Structural steel plate) Fish Passage Rating: Gray
 
Length(ft): 163.0
Inlet Type: Projecting
Outlet Type: Projecting
Corrugation Depth(in.): 2.0
Corrugation Width(in.): 6.0
Condition Rating(1-5): 3
Approach Angle: 39.0
Sedimentation At Inlet: No
Inlet Substrate: None
Outlet Substrate: None
InletOutlet
Width(ft):10.2 11.2
Height(ft):11.0 10.0
Apron Length(ft):
Water Depth(ft): 0.23
Rustline Height(ft):2.5
Substrate Depth(ft):0.0 0.0
Backwatered?: No
Baffles Present: No
Embedded?: No
Outfall Height: 1.7
Outfall Type: Free Fall In To Pool
Constriction Ratio: 0.63
Culvert Gradient: 1.79%
Max Slope:
Max Slope Length:
  Culvert Observations:
  1. Culvert gradient gray
  2. Constriction ratio gray
  3. Outfall height red

Stream Measurements

Stream SubstratesUpstreamDownstream
Dominant:BedrockBoulder
Subdominant:BoulderCobble
Stream Slope(deg.):
Stream Flow Stage:Medium
Stream Width Type Distance From
Crossing (ft)		 Stream
Width (ft)
Upstream ordinary high water 89.0 10.30
Upstream ordinary high water 114.0 13.20
Upstream ordinary high water 138.0 25.10

Elevations

Locator ID Culvert
Number		 River
Distance (ft)1		 Distance From
Crossing (ft)2		 Relative
Elevation (ft)
D/S Grade Ctrl (Thalweg) 0.00 97.53
D/S Water Surface Elev 0.00 97.85
D/S Tailcrest or 1st Thalweg 23.00 98.25
D/S Water Surface Elev (Tailwater control) 23.00 98.38
Outlet Pool Water Elev 30.00 98.43
Max Pool Depth 30.00 96.45
Outlet Invert (Invert out, on metal) 32.00 99.90
D/S Water Surface Elev (Invert out) 32.00 100.13
Inlet Culvert Invert (Invert in, on metal) 195.00 102.82
U/S Water Surface Elev (Invert in) 195.00 103.33
U/S Grade Ctrl (Thalweg) (1st resting, on substrate) 197.00 103.50
U/S Headwater (1st resting) 197.00 103.76

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: Visual Observation, Ground (A)
Comments: Unidentified salmonids upstream from culvert.

Fish Observations

No fish observations occurred during this survey.

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