Fish Passage Improvement site 30303068

Fish Passage Site 30303068

Coordinates (dec. deg.): 59.18661°, -158.76173°
Legal Description: S011S056W32
Region: Southwest
Road Name: Snake Lake Road

Datum: NAD83
Quad Name / ITM: Dillingham A-8
AWC Stream #:
Stream Name: Snake River tributary

Elevation:

Site Comments: None

Survey Date: Sep 19, 2012

Survey SWA12-DIL06

site photos

Project Supervisor: Gillian O'Doherty, Alaska Department of Fish and Game — Anchorage, AK
Observers: Gillian O'Doherty, Mark Eisenman

Overall Fish Passage Rating: Gray

Tidal: No
Backwatered: No

Step Pools: No
Construction Year:

Site Observations:

Culvert gradient gray
Constriction ratio gray
Inlet perch
Beaver Activity

Comments: Constriction is definitiely an issue, especially at high flows. Upstream width approximately 12 to 14 feet. Old beaver dams upstream and downstream from culvert.

Culvert Measurements

ID: 1

Structure Type: Circular pipe (Corrugated steel)

Fish Passage Rating: Gray

Length(ft): 30.4

Inlet Type: Projecting

Outlet Type: Projecting

Corrugation Depth(in.): 1.0

Corrugation Width(in.): 3.0

Condition Rating(1-5): 2

Approach Angle: 42.0

Sedimentation At Inlet: Yes

Inlet Substrate: None

Outlet Substrate: None

	Inlet	Outlet
Width(ft):	5.5	6.0
Height(ft):	5.7	5.9
Apron Length(ft):
Water Depth(ft):		1.37
Rustline Height(ft):	2.2
Substrate Depth(ft):	0.0	0.0

Backwatered?: No

Baffles Present: No

Embedded?: No

Outfall Height: 0.0

Outfall Type: Hydraulic Jump

Constriction Ratio:

Culvert Gradient: 1.02%

Max Slope:

Max Slope Length:

Culvert Observations:

Culvert gradient gray
Constriction ratio gray
Inlet perch
Beaver Activity

Stream Measurements

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

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

No stream width data available.

Elevations

Locator ID	River Distance (ft)¹	Relative Elevation (ft)
Road Elev		100.97
D/S Water Surface Elev	0.00	96.54
D/S Grade Ctrl (Thalweg) (head of d/s riffle through old pond)	0.00	94.08
D/S Water Surface Elev	39.00	95.02
D/S Tailcrest or 1st Thalweg (tailwater control; middle of channel 3)	39.00	94.27
Max Pool Depth (deepest point that could be measured; other spots may be deeper.)	56.00	90.72
Outlet Invert	81.00	93.95
D/S Water Surface Elev	81.00	95.32
Outlet Culvert Top	81.00	100.01
Inlet Culvert Top	111.40	100.00
U/S Water Surface Elev	111.40	96.15
Inlet Culvert Invert	111.40	94.26
U/S Water Surface Elev	144.40	96.36
U/S Grade Ctrl (Thalweg) (downstream of split channel; is run upstream for a long way)	144.40	94.70

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.