Fish Passage Site 20303514

Coordinates (dec. deg.): 60.97427°, -149.09608°
Legal Description: S010N002E09
Region: South Central
Road Name: Arlberg Avenue

Datum: NAD83
Quad Name / ITM: Seward D-6
AWC Stream #: 247-60-10250-2018-3130
Stream Name: Unnamed

Elevation:

Site Comments: Site on new extention of Arlberg Ave. Stream has confluence with a slough about 70 feet below culvert outlet. 20303515 is just up the road and is a large pipe arch..

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 UPD21-ALB01

Project Supervisor: Kim Clark, ADFG — Anchorage, AK
Observers: Kim Clark, Michael Mazzacavallo

Overall Fish Passage Rating: Green

Tidal: No
Backwatered: No

Step Pools: No
Construction Year: 2016


Comments: Willow stakes look good. Erosion on upstream bank opposite of rootwads, channel has downcut somewhat. Some survey stakes still present.

Culvert Measurements

ID: 1 Structure Type: Box culvert (Structural aluminum plate) Fish Passage Rating: Green
 
Length(ft): 85.9
Inlet Type: Projecting
Outlet Type: Projecting
Corrugation Depth(in.): 2.5
Corrugation Width(in.): 8.5
Condition Rating(1-5): 5
Approach Angle: 0.0
Sedimentation At Inlet: No
Inlet Substrate: Boulder
Outlet Substrate: Gravel
InletOutlet
Width(ft):16.13 16.23
Height(ft):6.48 4.77
Apron Length(ft):
Water Depth(ft): 0.47
Rustline Height(ft):
Substrate Depth(ft):1.77 3.48
Backwatered?: No
Baffles Present: No
Embedded?: Yes
Embedded Depth(ft): 1.77
Outfall Height: 0.0
Outfall Type: At Stream Grade
Constriction Ratio: 2.2
Culvert Gradient: 2.61%
Max Slope:
Max Slope Length:
 

Comments: as-built culvert dimensions are 13.1 ft by 8.25ft which was used to calculate substrate depth. Passage gradient using Water surface gradient = 2.16%.

Stream Measurements

Stream SubstratesUpstreamDownstream
Dominant:GravelGravel
Subdominant:BoulderCobble
Stream Slope(deg.):3.16
Stream Flow Stage:Medium
Stream Width Type Distance From
Crossing (ft)
Stream
Width (ft)
Upstream ordinary high water 96.0 7.40
Upstream ordinary high water 107.0 7.90
Upstream ordinary high water 117.0 7.30

Elevations

Locator ID Culvert
Number
River
Distance (ft)1
Distance From
Crossing (ft)2
Relative
Elevation (ft)
D/S Water Surface Elev 0.00 93.27
D/S Thalweg 0.00 92.42
D/S Thalweg 15.50 93.14
D/S Water Surface Elev 15.50 93.57
Outlet Invert 70.00 94.69
D/S Water Surface Elev 70.00 95.16
Outlet Culvert Top 70.00 100.51
Inlet Culvert Top 155.90 102.75
Inlet Culvert Invert 155.90 96.21
U/S Water Surface Elev 155.90 97.02
U/S Thalweg 166.40 96.62
U/S Water Surface Elev 166.40 97.37
U/S Water Surface Elev 184.50 97.98
U/S Thalweg 184.50 96.85
U/S Thalweg 187.00 97.28
U/S Water Surface Elev 187.00 98.01
U/S Thalweg 205.60 97.70
U/S Water Surface Elev 205.60 98.89
U/S Water Surface Elev 209.29 99.41
U/S Thalweg 209.29 98.85
U/S Water Surface Elev 220.40 99.88
U/S Thalweg 220.40 99.17

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