Fish Passage Site 20401294

Coordinates (dec. deg.): 61.52991°, -149.51996°
Legal Description: S017N001W30
Region: South Central
Road Name: West Halter Way

Datum: NAD83
Quad Name / ITM: Anchorage C-7
AWC Stream #: 247-50-10300-2022
Stream Name: Cottonwood Creek tributary

Elevation:

Site Comments: Private driveway w/ culvert over small drainage on the Robinson Family property yard.

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 MSB11-WHP01

Project Supervisor: Gillian O'Doherty, Alaska Department of Fish and Game — Anchorage, AK
Observers: John Greuey, Abraham Gioffre

Overall Fish Passage Rating: Gray

Tidal: No
Backwatered: No

Step Pools: No
Construction Year:


Site Observations:

  1. Culvert gradient gray
  2. Shallow fill; inadequate roadfill volume above culvert

Comments: Private driveway w/ culvert over small drainage on the Robinson Family property yard. Heaving asphalt above culvert. Stream channelized through yard upstream & downstream and lawn groomed down to waterline. Very slow flow at culvert, almost still shallow pool area.

Culvert Measurements

ID: 1 Structure Type: Circular pipe (Corrugated steel) Fish Passage Rating: Gray
 
Length(ft): 20.44
Inlet Type: Headwall
Outlet Type: Headwall
Corrugation Depth(in.): 0.5
Corrugation Width(in.): 3.0
Condition Rating(1-5): 3
Approach Angle: 3.0
Sedimentation At Inlet: No
Inlet Substrate: None
Outlet Substrate: None
InletOutlet
Width(ft):1.95 1.93
Height(ft):1.95 1.95
Apron Length(ft):0.0 0.0
Water Depth(ft): 0.16
Rustline Height(ft):0.4
Substrate Depth(ft):0.0 0.0
Backwatered?: No
Baffles Present: No
Embedded?: No
Embedded Depth(ft): 0.0
Outfall Height: 0.0
Outfall Type: At Stream Grade
Constriction Ratio: 1.2
Culvert Gradient: 0.88%
Max Slope:
Max Slope Length:
  Culvert Observations:
  1. Culvert gradient gray
  2. Shallow fill; inadequate roadfill volume above culvert

Stream Measurements

Stream SubstratesUpstreamDownstream
Dominant:Silt/ClaySilt/Clay
Subdominant:GravelGravel
Stream Slope(deg.):0
Stream Flow Stage:Low
Stream Width Type Distance From
Crossing (ft)		 Stream
Width (ft)
Downstream ordinary high water 13.0 1.85
Downstream ordinary high water 22.0 1.65
Downstream ordinary high water 34.0 1.35

Elevations

Locator ID Culvert
Number		 River
Distance (ft)1		 Distance From
Crossing (ft)2		 Relative
Elevation (ft)
D/S Water Surface Elev 0.00 96.17
D/S Thalweg (Profile point at top of small riffle.Not a real grade point.) 0.00 95.85
D/S Thalweg (Profile point at beginning of glide.) 30.00 95.75
D/S Water Surface Elev 30.00 96.17
D/S Water Surface Elev (Water surface at outlet invert.) 36.00 96.17
Outlet Invert (On pipe) 36.00 96.01
Road Elev (Road is a private drive off West Halter Way.) 46.00 99.35
Inlet Culvert Invert (On pipe) 56.44 96.19
U/S Water Surface Elev (Water surface at inlet invert) 56.44 96.46
U/S Water Surface Elev 68.44 96.51
U/S Thalweg (Profile point at glide upstream of inlet. No features. Substrate deeper than inverts.) 68.44 96.01

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

No fish sampling occurred during this survey.

Fish Observations

No fish observations occurred during this survey.

Questions or comments about this report can be directed to dfg.dsf.webmaster@alaska.gov