Road Stream Crossing Site AUS_RO008

Au Sable River Watershed, South Branch Au Sable River
AuSable Rd
AuSable Twp, Roscommon County
Information collected by:
Huron Pines
Site Location
GPS Coordinates: 44.4586 , -84.44375
T24N R01W Sec 21
Owned by Private
Fish Passability 0
Structure is NOT Perched
Total Erosion: 2.1724 tons/year
Severity: Severe
Year Inventoried: 2013
Crossing Information
Type of Crossing: culvert(s)
Number of Structures: 2
Structure Shape: Ellipse
Inlet Type: Mitered
Outlet Type: At Stream Grade
Structure Material: Metal
Structure Substrate: Rock
General Conditions: Good
Multiple Culverts/Spans
Culvert/Span
Width
Length
Height
Material
2
12 ft.
76 ft.
7.5 ft.
Metal
Structure Interior: corrugated
Dimensions of Structure: Length 76 ft. , Width 12 ft. , Height 7.5 ft.
Structure is NOT Perched
Structure Inlet
Water Depth: 1 ft.
Embedded Depth of Structure: 0.3 ft.
Water Velocity*: 2.42 ft./sec.
Structure Outlet
Water Depth: 0.8 ft.
Embedded Depth of Structure: 0.3 ft.
Water Velocity*: 3.57 ft./sec.
*Water Velocities were measured at the Surface (with Float Test)
Stream Information
Stream Flow: Less than Bankfull
Scour Pool: Length 67 ft. , Width 47 ft. , Depth 6.5 ft.
Upstream Pond: Length 0 ft. , Width 0 ft. , Depth 0 ft.
Riffle Information
Water Depth: 1.2 ft.
Bankfull Width: 44.1 ft.
Wetted Width: 36 ft.
Water Velocity: 0.6 ft./sec. (Measured with Float Test)
Dominant Substrate: Sand
Road Information
Paved County Road
Road Condition: Good
Road Width at Culvert: 35.7 ft.
Location of Low Point: At Stream
Runoff Path: Ditch
Embankments
Upstream
Fill Depth: 4.3 ft.
Slope: 1:2
Downstream
Fill Depth: 4 ft.
Slope: More than 1:2
Approaches
Left Approach
Length: 1000 ft.
Slope: 1% to 5%
Vegetation: Heavy
LS Factor: 0.57
Erosion: 0.6727 tons/year
Right Approach
Length: 610 ft.
Slope: 6% to 10%
Vegetation: Heavy
LS Factor: 1.749
Erosion: 1.2587 tons/year
Erosion Information
Total Erosion at Crossing: 2.1724 tons/year
Extent of Erosion: Moderate
Erosion is occurring and corrective actions can be installed to address the problem.
Notes: Mostly along downstream bank and some on upstream bank.
Location of Erosion
Erosion Dimensions
Eroded Material
Material Eroded
Total Erosion
facing downstream
Length
Width
Depth
Reaching Stream?
(tons/year)
Right Downstream
27 ft.
7.5 ft.
1.5 ft.
yes
Silt
0.241
Summary Information
Fish Passability 0
A future visit to this site is recommended. Silt fences need to be installed
These non-native species were observerd at this site: Spotted Knapweed