Road Stream Crossing Site AUS_CR034

Au Sable River Watershed, Tributary of East Branch Au Sable River
Roberts Rd
Grayling Twp, Crawford County
Information collected by:
Huron Pines
Site Location
GPS Coordinates: 44.67852 , -84.70759
T26N R03W Sec 6
Owned by Private
Fish Passability 0.9
Total Erosion: 0.424 tons/year
Severity: Moderate
Year Inventoried: 2013
Crossing Information
Type of Crossing: Other
Structure Shape: Round
Inlet Type: Other
Outlet Type: At Stream Grade
Structure Material: Metal
Structure Substrate: mixture
General Conditions: Poor
Structure Interior: corrugated
Structure is Rusted through
Dimensions of Structure: Length 40.5 ft. , Width 2 ft. , Height 2 ft.
Structure Inlet
Water Depth: 1.8 ft.
Embedded Depth of Structure: 0.2 ft.
Water Velocity*: 1.48 ft./sec.
Structure Outlet
Water Depth: 1.5 ft.
Embedded Depth of Structure: 0.6 ft.
Water Velocity*: 0.61 ft./sec.
*Water Velocities were measured at the Surface (with Float Test)
Stream Information
Stream Flow: Less than Bankfull
Scour Pool: Length 10 ft. , Width 9 ft. , Depth 1.6 ft.
Riffle Information
Water Depth: 0.8 ft.
Bankfull Width: 12.5 ft.
Wetted Width: 7.2 ft.
Water Velocity: 2.14 ft./sec. (Measured with Float Test)
Dominant Substrate: Organics
Road Information
Paved County Road
Road Condition: Poor
Road Width at Culvert: 22.5 ft.
Location of Low Point: Other
Runoff Path: Ditch
Fill Depth: 2.3 ft.
Slope: More than 1:2
Fill Depth: 2 ft.
Slope: 1:2
Left Approach
Length: 1000 ft.
Slope: 1% to 5%
Vegetation: Heavy
LS Factor: 0.57
Erosion: 0.424 tons/year
Length: 0 ft.
Slope: 0%
Vegetation: Heavy
LS Factor: 0
Erosion: 0 tons/year
Erosion Information
Total Erosion at Crossing: 0.424 tons/year
Extent of Erosion: Minor
Summary Information
Fish Passability 0.9
A future visit to this site is recommended. Scour pool is large downstream and culvert is rusty.