Fish Passage Improvement site 20501223

Fish Passage Site 20501223

Coordinates (dec. deg.): 61.48386°, -149.68298°
Legal Description: S016N002W17
Region: South Central
Road Name: Royal Lane

Datum: WGS84
Quad Name / ITM: Anchorage B-8
AWC Stream #:
Stream Name: O'Brien Creek

Elevation:

Site Comments: None

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 MSB09-RYL01

site photos

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

Overall Fish Passage Rating: Red

Tidal: No
Backwatered: No

Step Pools: No
Construction Year:

Site Observations:

Constriction ratio red
Culvert gradient red

Comments: Original assessment site photos missing. ***Updated site photos added from 6-8-15 site visit.

Culvert Measurements

ID: 1

Structure Type: Circular pipe (Corrugated steel)

Fish Passage Rating: Red

Length(ft): 39.6

Inlet Type: Projecting

Outlet Type: Projecting

Corrugation Depth(in.): 0.5

Corrugation Width(in.): 2.75

Condition Rating(1-5): 3

Approach Angle: 10.0

Sedimentation At Inlet: Yes

Inlet Substrate: Gravel

Outlet Substrate: Cobble

	Inlet	Outlet
Width(ft):	2.9	2.9
Height(ft):	1.7	2.1
Apron Length(ft):
Water Depth(ft):		0.83
Rustline Height(ft):	0.8
Substrate Depth(ft):	1.1	0.8

Backwatered?: No

Baffles Present: No

Embedded?: No

Outfall Height: 0.0

Outfall Type: At Stream Grade

Constriction Ratio: 0.2

Culvert Gradient: 1.14%

Max Slope:

Max Slope Length:

Culvert Observations:

Constriction ratio red
Culvert gradient red

Stream Measurements

Stream Substrates	Upstream	Downstream
Dominant:	Silt/Clay	Silt/Clay
Subdominant:	Silt/Clay	Sand

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

Stream Width Type	Distance From Crossing (ft)	Stream Width (ft)
Upstream ordinary high water	120.0	19.00
Upstream ordinary high water	175.0	12.50
Upstream ordinary high water	250.0	12.50

Elevations

Locator ID	Culvert Number	River Distance (ft)¹	Distance From Crossing (ft)²	Relative Elevation (ft)
Outlet Pool Water Elev	1			98.63
U/S Headwater	1			98.72
Inlet Road Edge	1			102.00
D/S Water Surface Elev (d/s WS)	1	0.00	109.0	97.10
D/S Water Surface Elev (d/s WS)	1	78.00	31.0	97.26
D/S Tailcrest or 1st Thalweg	1	106.60	2.4	98.15
D/S Water Surface Elev (WS @ TWC)	1	106.60	2.4	98.61
D/S Thalweg	1	107.50	1.5	98.00
Outlet Invert	1	109.00	0.0	97.80
Inlet Culvert Invert	1	148.60	0.0	98.25
U/S Grade Ctrl (Thalweg) (1st TC u/s)	1	150.00	1.4	98.44
U/S Water Surface Elev (WS @ GP)	1	150.00	1.4	98.92

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.