Road Stream Crossing Site EUP_41N4W13_004
Les Cheneaux Islands Watershed, Unnamed
Co Rd H-63
Mackinac County
Information collected by:
HNF USFS
Site Location
GPS Coordinates: 45.948953422,-84.7532445849999
T 041NN R 004W Sec 13
Fish Passability: Not a Barrier
Structure is NOT Perched
Total Erosion: 1.73 tons/year
Overall Score: 22
Severity: Moderate
Date Inventoried: 5/12/2021
Road Approach - Left
Road Approach - Right
Inlet
Upstream Conditions
Outlet
Downstream Conditions
Representative Reach
Other
Other
Site Sketch
Crossing Information*
Type of Crossing: Culvert(s)
Number of Structures: 1
Structure Shape: Native Bottom Arch
Inlet Type: Mitered
Outlet Type: At Stream Grade
Structure Material: Concrete
Structure Substrate: Sand
General Conditions: Major deterioration from corrosion or abrasion (5-10% of the structure is rusted through) or cracking or spalling or chipping (medium sized cracks, widespread chipping, exposed metal reinforcement). OR Major shape changes (described above) reducing the capacity of the structure by less than 30%. OR segment disconnection (segments of concrete or metal culvert disconnecting internally) but no evidence of water piping.
Structure Interior: Smooth
Is Structure Rusted through? No
Dimensions of Structure: Length 100 ft. Width 4.6 ft. Height 2.85 ft.
Percentage Plugged: None or 0%
Percentage Crushed: None or 0%
Structure is NOT Perched
Structure Inlet
Water Depth: 0.5 ft.
Embedded Depth of Structure: 0 ft.
Water Velocity*: 0.7 ft./sec.
Structure Outlet
Water Depth: 0.7 ft.
Embedded Depth of Structure: 0 ft.
Water Velocity*: 0.1 ft./sec.
*Water Velocities were measured 0.5 ft. below the surface (via Flow Meter).
Additional Comments
Updated by Huron Pines. L. Schmock, N. Theisen
Stream Information
Stream Flow: < 1/2 Bankfull – The stream channel is less than half filled with water.
Stream Flow Type: Perennial (if flowing during the time of assessment.)
Is Scour Pool Present? No
Is Upstream Ponding Present? Yes
Pond: Length 6.5 ft., Width 6 ft.
Riffle Information
Water Depth: 1 ft.
Bankfull Width: 8 ft.
Wetted Width: 4.2 ft.
Water Velocity: 0.1 ft./sec. (measured via Flow Meter)
Dominant Substrate: Sand – particles are smaller than a pinhead and feel gritty between fingers
Road Information
Road Surface: Paved
Owner: County
Road Condition: New Pavement or Well Graded, Same condition as initial placement.
Road Core Integrity: Good (no symptoms of lack of integrity)
Road Width at Culvert: 32 ft.
Location of Low Point: At Stream
Runoff Path: Ditch
Embankments
Upstream
Fill Depth: 3 ft.
Slope: Moderate, 2:1, 22.5°, or 41%
Downstream
Fill Depth: 2 ft.
Slope: Moderate, 2:1, 22.5°, or 41%
Approaches
Left Approach
Length: 1000 ft.
Slope: 1-5%
Vegetation: Partial, Ditch has some vegetation and some bare, eroding places.
Erosion Estimate: 0.85 tons/year
Right Approach
Length: 1500 ft.
Slope: 1-5%
Vegetation: Partial, Ditch has some vegetation and some bare, eroding places.
Erosion Estimate: 0.85 tons/year
Erosion Information
Estimate of Total Erosion at Crossing: 1.73 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) | ||
Right Upstream Streambank | 4 ft. | 1 ft. | 1 ft. | Yes | Sandy Loam | Moderate | 0.03 |
Right Downstream Streambank | 6 ft. | 6 ft. | 2 ft. | Yes | Sandy Loam | Moderate (corrective actions recommended) | |
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? Yes, Spotted knapweed.
Site Comments: Misaligned culvert. ORV ford just upstream and perched rocks in between the two.
*These data are maintained in the Michigan DNR Road Stream Crossing Inventory.