Bobs Lake Dam 1 Bobs Lake Dam History of Dams at Site History - - PowerPoint PPT Presentation

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Bobs Lake Dam

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Bobs Lake Dam – History of Dams at Site

History

• Dams at outlet of Bobs Lake date back to 1821
• Government of Canada purchased the dam site in 1870
• In 1871 the size of the dam was significantly increased and

Bobs Lake’s place as a reservoir for the Tay and the Rideau Canals was enhanced.

• Concrete dam dates to around 1930 – several major

repairs and rehabilitations to date

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Bobs Lake Dam

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Bobs Lake Dam

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Bobs Lake Dam – Current

• A Dam Safety Review concluded that the dam is in poor

condition and did not satisfy dam safety guidelines

• In June 2015, major rehabilitation work was announced for

Bobs Lake Dam

• Following geotechnical analysis of the existing dam site, the

rock was determined to be of poor quality.

• As a result of this analysis, in May 2016 the Government of

Canada announced additional resources in order to complete the full replacement of the Bobs Lake Dam

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Bobs Lake Dam

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Bobs Lake Dam – Replacement

• Plan is for dam to be located about 40m upstream of existing

site near the location of remnants from an older dam

• Water management strategy / approach will not change due to

construction – old dam will continue pass water until new dam is built

• A second spillway will be added in order to meet current

Canadian Dam Association safety guidelines. A second spillway will not alter water management practises, it is being added as a redundancy in case one spillway is blocked (for ex.)

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Bobs Lake Dam – Site of new dam

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Bobs Lake Dam – Preparations

• Environmental Assessment has progressed
• More detailed Fish Habitat Assessment and Species at Risk

Study completed

• Enhanced environmental investigation and design work for

stream channel rehabilitation between old and new dam with intent of creating Walleye spawning zone

• Archaeology undertaken on provincial property and marine
• areas. Federal property disturbed by previous projects
• Engagement with Algonquin First Nation of Ontario underway

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Bobs Lake Dam – Considerations

• In-water work timing restriction March 15-June 30 to protect

warm and coolwater spawners (i.e. Walleye)

• Downstream flow will be maintained throughout project
• Some fish habitat loss as the approximate 40m section between

the old dam and new dam will switch from lake habitat to river habitat; however, new channel designed to allow for Walleye spawning and includes riparian planting of trees, shrubs and grasses

• Mitigations for species at risk (Gray Ratsnake, Blanding’s

Turtle, Snapping Turtle, Butternut)

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Bobs Lake Dam – Next Steps

Further investigation and preparation work still underway:

• Fisheries permitting (currently under DFO review)
• Completion of Detailed Impact Assessment
• Completion of design, tender and award contract
• Property right of way purchase for long term access and lease for

construction

• Liaison with township on new access entrance
• Continued community engagement

As a result of outstanding project requirements and importance of timing window: Construction target now Summer 2018

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For further information on infrastructure projects: www.pc.gc.ca/rcInfrastructure To be added to the community engagement list – email RideauCanal.info@pc.gc.ca and include Bobs Lake in the subject heading Or Contact: Darryl Whitehead External Relations Manager, Infrastructure Darryl.Whitehead@pc.gc.ca