Road Stream Crossing Site AUS_CR020
Au Sable River Watershed, East Branch Au Sable River
Lewiston Grade Rd
Grayling Twp,
Crawford County
Information collected by:
Site Location
GPS Coordinates: 44.73574
, -84.64178
T27N
R03W
Sec 14
Owned by State
Fish Passability 0
Total Erosion: 0.4475 tons/year
Severity: Severe
Year Inventoried: 2013
Crossing Information
Type of Crossing: Bridge
Structure Shape: Open Bottom Square/Rectangle
Inlet Type: Other
Outlet Type: At Stream Grade
Structure Material: Wood
Structure Substrate: Sand
General Conditions: Good
Structure Interior: smooth
Dimensions of Structure: Length 17.7 ft.
, Width 22.1 ft.
, Height 5.4 ft.
Structure Inlet
Water Depth: 1.8 ft.
Water Velocity*: 3.3 ft./sec.
Structure Outlet
Water Depth: 2.5 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 36 ft.
, Width 44 ft.
, Depth 3.6 ft.
Upstream Pond: Length 65 ft.
, Width 32 ft.
Riffle Information
Water Depth: 1.6 ft.
Bankfull Width: 32 ft.
Wetted Width: 28 ft.
Water Velocity: 1.67 ft./sec.
(Measured with Float Test)
Dominant Substrate: Sand
Road Information
Gravel
County Road
Road Condition: Fair
Road Width at Culvert: 14 ft.
Location of Low Point: Other
Runoff Path: Ditch
Fill Depth: 0 ft.
Slope: Vertical
Fill Depth: 0 ft.
Slope: Vertical
Length: 0 ft.
Slope: 0%
Vegetation: Heavy
LS Factor: 0
Erosion: 0 tons/year
Right Approach
Length: 260 ft.
Slope: 1% to 5%
Vegetation: Heavy
LS Factor: 0.444
Erosion: 0.4452 tons/year
Erosion Information
Total Erosion at Crossing: 0.4475 tons/year
Extent of Erosion: Minor
Erosion is occurring and corrective actions can be installed to address the problem.
Location of Erosion | Erosion Dimensions | Eroded Material | Material Eroded | Total Erosion | ||
facing downstream | Length | Width | Depth | Reaching Stream? | (tons/year) | |
Right Approach |
11.5 ft. |
4 ft. |
0.2 ft. |
no |
Gravel |
0.0023 |
Summary Information
Fish Passability 0
A future visit to this site is recommended. To check on scour pool and upstream pond to make sure that size is increasing.
These non-native species were observerd at this site: Spotted Knapweed, Quenn Anne's Lace