Fish Passage Improvement site 20401281

Fish Passage Site 20401281

Coordinates (dec. deg.): 61.52639°, -149.51169°
Legal Description: S017N001W31
Region: South Central
Road Name: driveway - 2420 Trapline Drive

Datum: NAD83
Quad Name / ITM: Anchorage C-7
AWC Stream #: 247-50-10300-2012
Stream Name: Cottonwood Slough

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 MSCS1-CT130

site photos

Observers: Doug Hill, Joe Conner, Sharie Chrisco

Overall Fish Passage Rating: Gray

Tidal: No
Backwatered: No

Step Pools:
Construction Year:

Comments: None

Culvert Measurements

ID: 1

Structure Type: Circular pipe (Corrugated Metal)

Fish Passage Rating: Gray

Length(ft): 42.0

Inlet Type: Projecting

Outlet Type:

Corrugation Depth(in.): 1.0

Corrugation Width(in.): 3.0

Condition Rating(1-5):

Approach Angle:

Sedimentation At Inlet:

Inlet Substrate: Silt/Clay

Outlet Substrate: Silt/Clay

	Inlet	Outlet
Width(ft):	3.0	3.0
Height(ft):	1.6	1.7
Apron Length(ft):
Water Depth(ft):	0.6	0.7
Rustline Height(ft):
Substrate Depth(ft):	1.4	1.3

Backwatered?:

Baffles Present: No

Embedded?: No

Outfall Height:

Outfall Type:

Constriction Ratio:

Culvert Gradient: 0.24%

Max Slope:

Max Slope Length:

Culvert Observations:

None of this type

Stream Measurements

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

Stream Slope(deg.):
Stream Flow Stage:

Stream Width Type	Distance From Crossing (ft)	Stream Width (ft)
Downstream ordinary high water	40.0	10.80
Upstream ordinary high water	50.0	12.30

Elevations

Locator ID	Culvert Number	River Distance (ft)¹	Distance From Crossing (ft)²	Relative Elevation (ft)
U/S Thalweg				90.18
Outlet Culvert Top	1			91.55
Inlet Culvert Top	1			91.67
D/S Thalweg		0.00	40.0	89.76
D/S Thalweg (Base of run below outlet)		28.20	11.8	89.95
Outlet Invert	1	40.00	0.0	89.95
Outlet Thalweg	1	40.00	0.0	89.95
Road Elev		61.00		95.93
Road Elev		61.00		95.97
Inlet Culvert Invert	1	82.00	0.0	90.05
Inlet Thalweg	1	82.00	0.0	90.05

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.

Fish Sampling Efforts

No fish sampling occurred during this survey.

Fish Observations

No fish observations occurred during this survey.

Photos

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