Fish Passage Site 20401277

Coordinates (dec. deg.): 61.59575°, -149.35993°
Legal Description: S017N001W01
Region: South Central
Road Name: Seward Meridian Road

Datum: NAD83
Quad Name / ITM: Anchorage C-7
AWC Stream #: 247-50-10300
Stream Name: Cottonwood Creek

Elevation:

Site Comments: Pedestrian bridge at outlet; wide pond-like at culvert inlet; downstream 100' - wide wetland channel (Wasilla Lake).

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 MSCS1-CT126

Observers: Doug Hill, Joe Conner, Michael Wheel

Overall Fish Passage Rating: Green

Tidal: No
Backwatered: No

Step Pools:
Construction Year:


Comments: River Right - 50' of riprap downstream of culvert; River Left - 90' of riprap downstream of culvert; Pedestrian bridge at outlet; wide pond-like at culvert inlet; downstream 100' - wide wetland channel (Wasilla Lake).

Culvert Measurements

ID: 1 Structure Type: Open-bottom arch (Strutural Metal Plate) Fish Passage Rating: Green
 
Length(ft): 90.0
Inlet Type: Mitered
Outlet Type:
Corrugation Depth(in.): 1.0
Corrugation Width(in.): 3.0
Condition Rating(1-5):
Approach Angle:
Sedimentation At Inlet:
Inlet Substrate: Gravel
Outlet Substrate: Gravel
InletOutlet
Width(ft):9.0 9.0
Height(ft):4.4 5.7
Apron Length(ft):
Water Depth(ft):0.6 1.8
Rustline Height(ft):
Substrate Depth(ft):
Backwatered?:
Baffles Present: No
Embedded?: No
Outfall Height:
Outfall Type:
Constriction Ratio:
Culvert Gradient: 0.11%
Max Slope:
Max Slope Length:
  Culvert Observations:
  1. None of this type

Stream Measurements

Stream SubstratesUpstreamDownstream
Dominant:GravelGravel
Subdominant:
Stream Slope(deg.):
Stream Flow Stage:Medium
Stream Width Type Distance From
Crossing (ft)		 Stream
Width (ft)
Downstream ordinary high water 50.0 25.80

Elevations

Locator ID Culvert
Number		 River
Distance (ft)1		 Distance From
Crossing (ft)2		 Relative
Elevation (ft)
D/S Thalweg 78.38
D/S Thalweg 83.59
Outlet Culvert Top 1 89.79
Inlet Culvert Top 1 89.89
Outlet Invert 1 0.00 0.0 84.02
Outlet Thalweg 1 0.00 0.0 84.02
Road Elev 45.00 97.62
Road Elev 45.00 98.25
Inlet Culvert Invert 1 90.00 0.0 85.25
Inlet Thalweg 1 90.00 0.0 85.25
U/S Thalweg 105.60 15.6 84.40

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 (C)

Fish Observations

Species: adult coho salmon Life History: Anadromous
Total Fish Observed: Fish Measured: Fork Lengths (mm) Min: Max: Mean:
Collected/Observed by Gear Type: Upstream Visual Observation, Ground ()  
Comments: 8 adult cohos observed moving thru culvert (same info applied to 126D1 in database)

Photos

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