Road Stream Crossing Site EUP_MCW25
Les Cheneaux Islands Watershed
S Prentiss Bay Road
Chippewa County
Information collected by:
Site Location
GPS Coordinates: 46.0032278,-84.2161314
T 042N R 002 Sec 29
Fish Passability: Not a Barrier
Structure is NOT Perched
Total Erosion: 0.97 tons/year
Overall Score: 24
Severity: Moderate
Date Inventoried: 5/26/2021
Road Approach - Left
Road Approach - Right
Inlet
Upstream Conditions
Outlet
Downstream Conditions
Representative Reach
Site Sketch
Crossing Information*
Type of Crossing: Culvert(s)
Number of Structures: 1
Structure Shape: Round
Inlet Type: Projecting
Outlet Type: At Stream Grade
Structure Material: Plastic
Structure Substrate: Mixture
General Conditions: Moderate deterioration from corrosion or abrasion (small rust flakes or indication that rust is slightly deeper than the surface level) or cracking or spalling or chipping (few minor cracks or localized chipping in the concrete). OR minor shape changes (described above).
Structure Interior: Smooth
Is Structure Rusted through? No
Dimensions of Structure: Length 20 ft. Width 4 ft. Height 4 ft.
Percentage Plugged: 1% - 20% Inside,Outlet
Percentage Crushed: 1% - 20%
Structure is NOT Perched
Structure Inlet
Water Depth: 1.1 ft.
Embedded Depth of Structure: 0.1 ft.
Water Velocity*: 0.1 ft./sec.
Structure Outlet
Water Depth: 1.3 ft.
Embedded Depth of Structure: 0.1 ft.
Water Velocity*: 0.1 ft./sec.
*Water Velocities were measured 1 ft. below the surface (via Flow Meter).
Stream Information
Stream Flow: < Bankfull – The stream channel is more than half filled with water, but is not full.
Stream Flow Type: Perennial (if flowing during the time of assessment.)
Is Scour Pool Present? No
Is Upstream Ponding Present? No
Riffle Information
Water Depth: 0.5 ft.
Bankfull Width: 6.5 ft.
Wetted Width: 5 ft.
Water Velocity: 0.8 ft./sec. (measured via Flow Meter)
Dominant Substrate: Gravel – rocks between the size of a pinhead and a baseball
Road Information
Road Surface: Gravel
Owner: State
Road Condition: Old Pavement or Rutted, Minor cracking or rutting/ponding at crossing all or part of crossing length.
Road Core Integrity: Fair (some of the symptoms may be present, but not to an extent posing high risk to the crossing)
Road Width at Culvert: 13 ft.
Location of Low Point: At Stream
Runoff Path: Ditch
Embankments
Upstream
Fill Depth: 2 ft.
Slope: Moderate, 2:1, 22.5°, or 41%
Downstream
Fill Depth: 2.5 ft.
Slope: Steep, 1:1, 45°, or 100%
Approaches
Left Approach
Length: 320 ft.
Slope: 1-5%
Vegetation: Heavy, Ditch is fully vegetated or rip-rapped with no signs of erosion.
Erosion Estimate: 0.53 tons/year
Right Approach
Length: 206 ft.
Slope: 1-5%
Vegetation: Heavy, Ditch is fully vegetated or rip-rapped with no signs of erosion.
Erosion Estimate: 0.32 tons/year
Erosion Information
Estimate of Total Erosion at Crossing: 0.97 tons/year
Location of Erosion | Erosion Dimensions | Eroded Material | Material Eroded | Extent of Erosion | Estimated Erosion | ||
facing downstream | Length | Width | Depth | Reaching Stream? | (tons/year) | ||
Left Upstream Embankment1 | 3 ft. | 2 ft. | 3 ft. | Yes | Gravel | Severe (corrective actions recommended) | 0.12 |
1Foot traffic to culvert has probably accelerated the erosion
Summary Information
Fish Passability: Not a Barrier
Is a future visit to this site recommended? No
Were any non-native species observerd at this site? No
Site Comments: Road
*These data are maintained in the Michigan DNR Road Stream Crossing Inventory.