Fish Passage Improvement site 30303070

Fish Passage Site 30303070

Coordinates (dec. deg.): 59.15761°, -158.63550°
Legal Description: S012S056W12
Region: Southwest
Road Name: Aleknagik Lake Road

Datum: NAD83
Quad Name / ITM: Dillingham A-8
AWC Stream #:
Stream Name: Belt Creek tributary

Elevation:

Site Comments: None

Survey Date: Sep 19, 2012

Survey SWA12-DIL08

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: Red

Tidal: No
Backwatered: No

Step Pools: No
Construction Year:

Site Observations:

Outfall height red
Culvert gradient gray
Beaver Activity

Comments: Substrate depth at inlet is at end of miter. Height and width also at end of miter. Creek most likely steeper upstream.

Culvert Measurements

ID: 1

Structure Type: Pipe-arch (Structural steel plate)

Fish Passage Rating: Red

Length(ft): 55.0

Inlet Type: Mitered

Outlet Type: Mitered

Corrugation Depth(in.): 2.0

Corrugation Width(in.): 6.0

Condition Rating(1-5): 3

Approach Angle: 11.0

Sedimentation At Inlet: Yes

Inlet Substrate: Cobble

Outlet Substrate: None

	Inlet	Outlet
Width(ft):	6.9	7.0
Height(ft):	4.6	5.1
Apron Length(ft):
Water Depth(ft):		0.4
Rustline Height(ft):	0.9
Substrate Depth(ft):	0.2	0.0

Backwatered?: No

Baffles Present: No

Embedded?: No

Outfall Height: 1.08

Outfall Type: Free Fall In To Pool

Constriction Ratio: 1.5

Culvert Gradient: 1.36%

Max Slope:

Max Slope Length:

Comments: Top of miter length is 43.5 feet.

Culvert Observations:

Outfall height red
Culvert gradient gray
Beaver Activity

Stream Measurements

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

Stream Slope(deg.):	0.56
Stream Flow Stage:	High

Stream Width Type	Distance From Crossing (ft)	Stream Width (ft)
Upstream ordinary high water	38.0	5.20
Upstream ordinary high water	66.0	5.20
Upstream ordinary high water	103.0	3.40

Elevations

Locator ID	River Distance (ft)¹	Relative Elevation (ft)
Road Elev		100.00
D/S Grade Ctrl (Thalweg)	0.00	86.02
D/S Water Surface Elev	0.00	86.51
D/S Water Surface Elev	21.00	86.92
D/S Tailcrest or 1st Thalweg (tailwater control)	21.00	86.47
Max Pool Depth	26.00	85.81
D/S Water Surface Elev	26.00	87.01
Outlet Invert (on pipe)	29.00	87.69
D/S Water Surface Elev	29.00	88.09
Outlet Culvert Top	35.00	92.81
Inlet Culvert Top	78.50	93.40
U/S Water Surface Elev	85.50	88.99
Inlet Culvert Invert (on substrate)	85.50	88.36
U/S Grade Ctrl (Thalweg) (in horsetail section on head of inlet riffle)	111.50	88.76
U/S Water Surface Elev	111.50	89.38
U/S Water Surface Elev	180.50	89.77
U/S Grade Ctrl (Thalweg)	180.50	88.87

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.