Fish Passage Site 20501401

Coordinates (dec. deg.): 62.35430°, -150.66295°
Legal Description: S026N008W12
Region: South Central
Road Name: Petersville Road

Datum: NAD83
Quad Name / ITM: Talkeetna B-2
AWC Stream #: 247-41-10200-2081-3181
Stream Name: Twentymile Creek

Elevation:

Site Comments: SUSITNA RIVER WATERSHED

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 PRK09-PVR30

Project Supervisor: Gillian O'Doherty, ADFG
Observers: Heidi Zimmer, Ben Histand

Overall Fish Passage Rating: Green

Tidal: No
Backwatered: No

Step Pools:
Construction Year:


Site Observations:

  1. None of this type

Comments: Resurvey of PRK041A038. Nearly embedded; substrate throughout may function like a streambed.

Culvert Measurements

ID: 1 Structure Type: Pipe-arch (Structural steel plate) Fish Passage Rating: Green
 
Length(ft): 60.0
Inlet Type: Projecting
Outlet Type: Projecting
Corrugation Depth(in.): 2.0
Corrugation Width(in.): 6.0
Condition Rating(1-5): 3
Approach Angle: 18.0
Sedimentation At Inlet: No
Inlet Substrate: Gravel
Outlet Substrate: Gravel
InletOutlet
Width(ft):12.0 12.0
Height(ft):6.7 7.0
Apron Length(ft):
Water Depth(ft): 0.32
Rustline Height(ft):
Substrate Depth(ft):1.7 1.4
Backwatered?: No
Baffles Present: No
Embedded?: No
Outfall Height: 0.0
Outfall Type: At Stream Grade
Constriction Ratio: 0.78
Culvert Gradient: 0.23%
Max Slope:
Max Slope Length:
  Culvert Observations:
  1. None of this type

Stream Measurements

Stream SubstratesUpstreamDownstream
Dominant:Silt/ClaySand
Subdominant:Silt/ClaySilt/Clay
Stream Slope(deg.):
Stream Flow Stage:Medium
Stream Width Type Distance From
Crossing (ft)		 Stream
Width (ft)
Upstream ordinary high water 100.0 15.50
Upstream ordinary high water 150.0 16.50
Upstream ordinary high water 200.0 14.00

Elevations

Locator ID Culvert
Number		 River
Distance (ft)1		 Distance From
Crossing (ft)2		 Relative
Elevation (ft)
Outlet Pool Water Elev 1 92.30
U/S Headwater 1 92.37
D/S Water Surface Elev (u/s WS for u/s gradient) 1 0.00 100.0 92.46
D/S Grade Ctrl (Thalweg) 1 27.00 73.0 91.38
D/S Water Surface Elev (WS @ GP) 1 27.00 73.0 91.50
D/S Tailcrest or 1st Thalweg 1 58.00 42.0 92.08
D/S Water Surface Elev (WS @ TWC) 1 58.00 42.0 92.24
D/S Thalweg (bottom of out pool) 1 93.00 7.0 91.91
D/S Water Surface Elev 1 96.50 3.5 92.46
Outlet Invert (on substrate) 1 100.00 0.0 91.98
Road Elev 1 130.00 102.85
Inlet Culvert Invert (on substrate in thalweg) 1 160.00 0.0 92.12
U/S Grade Ctrl (Thalweg) 1 163.50 3.5 92.37

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