1. Little Rapids Habitat Restoration St
Little Rapids Habitat Restoration St. Marys River AOC Sugar Island Township Meeting Engineering and Design Project Update January 8,2013

2. Why Restore the Rapids?
Rapids are productive habitat for a number of important species.
Much of the historic rapids in the St. Marys River have been destroyed.
Habitat is limiting fishery populations in the St. Marys River.
An improved fishery will have economic benefits.
Lake Whitefish
Lake Herring
Lake Sturgeon
Walleye
Main Rapids
Rapids btwn Sugar Island and Neebish Island
West of Neebish Island
Little Rapids 1 3 4 2

3. Where are we in the project?
We are in the study and design phase. No decisions on what to build (or whether to build) have been made.
We are refining our analysis and design and getting input from interested local citizens through meetings like this one.
Ayers Study (late 90’s) and Recovery Act proposal
March 20, 2012 – General Information Meeting as part of the Sportsman’s Club Meeting
November 13, 2012 – Combined BPAC and public meeting on project progress
November 14, 2012 – Meeting with Sugar Island Twp. Board and others
FAQ and design changes were created to address questions from public meetings.
Today’s meeting will provide refined alternatives that includes incorporation of comments from previous meetings.

4. Culverts w/ 2 lane MOT ($5,033,694)
Alternatives
400’ - 600' Crossing
Bridge w/ 2 lane MOT ($4,393,500)
Full Length Fishing
($5,251,560)
Raised for small craft
($5,651,560)
($4,893,500)
Fishing at Ends
($5,293,500)
Culverts w/ 2 lane MOT ($5,033,694)
($6,020,394)
($6,420,394)
($5,533,694)
($5,933,694)
400’ to 600’ opening provides restoration of desired habitat within funding.
Bridge and culvert options have different capital and O&M costs. Two lanes of traffic during construction will be maintained.
Fishing options will provide recreation access for all users.
Profile of causeway will be raised to accommodate small craft. Approximate rise will be between 3’ to 11’.

5. Impacts Related to Construction:
Noise
Air quality
Transportation
Utilities
Cultural Resources

9. Summary of Alternatives
Length (up to 600 ft with 1 or 2 spans)
Bridge or culverts (3-sided, 4-sided)
Width (pedestrian access and/ or parking)
Fishing access (on bridge or near bridge)
Small craft passage
Choices related to these alternatives drive the costs and benefits!

10. Summary of Results and Impacts
Modifying the causeway will increase velocity and flow in Little Rapids, but not have significant impacts anywhere else.
Velocities in the Lower Little Rapids will increase under restoration alternatives reducing ice formation.
Island residents and visitors will experience temporary impacts to during construction.
Valuable high quality habitat can be restored. Acreage restored varies depending on the span and location of bridge/ culverts and flow conditions.

11. Velocities, water depths and flow are identical for all alternatives considered for most of the study area. Only near the Little Rapids area are differences predicted (See Table Inset for differences).
Diff. between Existing Conditions and No Causeway at 82,000 CFS
Location
Discharge
(CFS)
Max
Velocity
(feet/sec)
Water Surface
Elevation
(feet IGLD)
Shipping Channel
-3,742
-0.2
0.0
North Channel
-176
Lower Little Rapids
3,918
3.0
-0.1
St. Marys River below Cloverland Power Canal
Velocities comparison for existing conditions and no causeway conditions

12. Impacts Related to Velocity:
Ice formation
Water quality
Aquatic life
Recreation
Velocities above and below the causeway under existing conditions are less than 0.1 m/s (0.33 ft/s)
Velocities above and below the causeway with a 600’ bridge under high flow conditions are a maximum of 1.15 m/s (3.8 ft/s)
Velocities comparison for 600’ bridge under high flow conditions of 3,596 m3/s (127,000 f3/s)

13. Next Steps A preferred alternative will be selected
Length, width, etc
Detailed design of causeway modifications
Environmental Assessment and Permitting
Construction

14. Little Rapids Habitat Restoration St
Little Rapids Habitat Restoration St. Marys River AOC Sugar Island Township Meeting Engineering and Design Project Update January 8,2013