Fish Passage Improvement site 20501429

Fish Passage Site 20501429

Coordinates (dec. deg.): 61.64582°, -149.87640°
Legal Description: S018N003W18
Region: South Central
Road Name: Parks Highway

Datum: NAD83
Quad Name / ITM: Anchorage C-8
AWC Stream #: 247-41-10100-2231-3018
Stream Name: Unnamed

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 MSB23-MS070

site photos

Project Supervisor: Michael Mazzacavallo, Alaska Department of Fish and Game — Anchorage, AK
Observers: Michael Mazzacavallo, Kat Leavitt, Beth Evers

Overall Fish Passage Rating: Red

Tidal: No
Backwatered: No

Step Pools: No
Construction Year:

Site Observations:

Culvert sagging in middle
Constriction ratio red
Culvert gradient red

Comments: The culvert is sagging in the middle. Outlet feeds an additional culvert downstream that goes under railroad tracks. Inlet is fed by pond on private property through an additional culvert.

Culvert Measurements

ID: 1

Structure Type: Circular pipe (Corrugated steel)

Fish Passage Rating: Red

Length(ft): 171.68

Inlet Type: Flared Inlet

Outlet Type: Flared Inlet

Corrugation Depth(in.): 0.5

Corrugation Width(in.): 3.0

Condition Rating(1-5): 3

Approach Angle: 33.0

Sedimentation At Inlet: No

Inlet Substrate: Cobble

Outlet Substrate: Cobble

	Inlet	Outlet
Width(ft):	3.0	3.0
Height(ft):	3.1	3.1
Apron Length(ft):	3.7	4.0
Water Depth(ft):	0.0	0.65
Rustline Height(ft):	1.1
Substrate Depth(ft):	0.0	0.0

Backwatered?: No

Baffles Present: No

Embedded?: No

Embedded Depth(ft): 0.0

Outfall Height: 0.8

Outfall Type: Cascade Over Rip-Rap

Constriction Ratio: 0.31

Culvert Gradient: 4.21%

Max Slope:

Max Slope Length:

Culvert Observations:

Culvert sagging in middle
Constriction ratio red
Culvert gradient red

Stream Measurements

Stream Substrates	Upstream	Downstream
Dominant:	Cobble	Cobble
Subdominant:	Gravel	Gravel

Stream Slope(deg.):	4.61
Stream Flow Stage:	High

Stream Width Type	Distance From Crossing (ft)	Stream Width (ft)
Upstream ordinary high water	26.0	13.40
Upstream ordinary high water	40.0	6.90
Upstream ordinary high water	54.0	12.40
Upstream ordinary high water	68.0	6.50

Elevations

Locator ID	River Distance (ft)¹	Relative Elevation (ft)
Road Elev		100.04
D/S Thalweg	0.00	68.35
D/S Water Surface Elev	0.00	69.11
D/S Thalweg	25.00	69.80
D/S Water Surface Elev	25.00	70.63
D/S Thalweg	43.00	70.74
D/S Water Surface Elev	43.00	71.70
D/S Thalweg (Apron Top)	56.00	72.24
D/S Water Surface Elev (Apron Bottom)	56.00	72.48
D/S Water Surface Elev	61.00	72.95
Outlet Culvert Top	61.00	75.49
Outlet Invert	61.00	72.30
Inlet Culvert Invert	232.68	79.62
U/S Water Surface Elev	232.68	80.63
Inlet Culvert Top	232.68	82.72
U/S Water Surface Elev (Apron WS)	237.68	80.68
U/S Thalweg (Apron Top)	237.68	79.65
U/S Thalweg	282.68	81.87
U/S Water Surface Elev	282.68	82.38
U/S Thalweg	310.68	82.83
U/S Water Surface Elev	310.68	83.44

Notes:

River distance is measured continuously throughout the survey reach along the thalweg of the stream.
Measured from each end of the crossing along the thalweg of the stream.