Road Stream Crossing Site AUS_CR042

Au Sable River Watershed, Tributary of Ausable River
North Down River Rd
Grayling Twp, Crawford County
Information collected by:
Huron Pines
Site Location
GPS Coordinates: 44.68448 , -84.67837
T26N R03W Sec 4
Owned by Private
Total Erosion: 0.8656 tons/year
Severity: Moderate
Year Inventoried: 2013
Crossing Information
Type of Crossing: Other
Structure Shape: Round
Inlet Type: Apron
Outlet Type: Outlet Apron
Structure Material: Metal
Structure Substrate: None
General Conditions: Good
Structure Interior: corrugated
Dimensions of Structure: Length 57 ft. , Width 1.6 ft. , Height 1.6 ft.
Structure Inlet
Water Depth: 0.2 ft.
Water Velocity*: 2 ft./sec.
Structure Outlet
Water Depth: 0.5 ft.
Water Velocity*: 0.31 ft./sec.
*Water Velocities were measured at the Surface (with Float Test)
Stream Information
Stream Flow: Less than 1/2 Bankfull
Riffle Information
Water Depth: 0.3 ft.
Bankfull Width: 33 ft.
Wetted Width: 17.5 ft.
Water Velocity: 0.125 ft./sec. (Measured with Float Test)
Dominant Substrate: Gravel
Road Information
Paved County Road
Road Condition: Good
Road Width at Culvert: 40 ft.
Location of Low Point: Other
Runoff Path: Ditch
Fill Depth: 1.4 ft.
Slope: More than 1:2
Fill Depth: 2 ft.
Slope: More than 1:2
Left Approach
Length: 460 ft.
Slope: 1% to 5%
Vegetation: Partial
LS Factor: 0.624
Erosion: 0.3796 tons/year
Length: 0 ft.
Slope: Less Than 1%
Vegetation: Partial
LS Factor: 0
Erosion: 0 tons/year
Erosion Information
Total Erosion at Crossing: 0.8656 tons/year
Extent of Erosion: Severe

Severe erosion above and around culvert on left approach upstream side. Also minor erosion above culvert on left approach downstream side.

Summary Information
Erosion is an area of concern for this site.

Severe erosion above/ alongside culvert at left upstream approach.

A future visit to this site is recommended.

Revegetate the road shoulder