Community Update: Update on Construction

Contractor setting up the diversion channel

August 30, 2018 – Parks Canada’s project to replace the Bobs Lake Dam has continued to progress and this week a milestone will be passed with the completion and certification of the temporary coffer dam and the commissioning of a water diversion channel around the construction site. As the certification and commissioning processes are underway nearby residents along the Tay River may notice minor and intermittent fluctuations of water flow as the structures are tested. This work is not expected to have an impact on lake levels of either Bobs or Christie Lakes.

Cofferdams are temporary in-water structures that are used to create dry work spaces in areas that would otherwise be underwater. In this instance, the cofferdam is being built using metal sheet piles that are driven into the bed of the lake. Rock fill is then used to provide additional structure. The coffer dam that is now in place will be supplemented with a downstream coffer dam that will complete the process of isolating the worksite from the water of Bobs Lake.

In order to manage water within the Tay watershed a diversion channel has been created adjacent to the work site. The diversion channel has an operable inlet with log settings much like the existing dam and has also been designed to provide the same water management capacity as the dam. The use of a diversion channel as part of this project will not have any impact on water levels in either the up or down stream areas.

While initial construction plans called for a two-phase approach using two separate coffer dam structures, the use of a diversion channel will allow the new dam to be constructed almost entirely in one phase.

Replacement of the Bobs Lake Dam at Bolingbroke

The replacement of the Bobs Lake Dam is part of Parks Canada’s unprecedented $3 billion dollar investment over 5 years to support infrastructure work to heritage, visitor, waterway and highway assets located within national historic sites, national parks, and national marine conservation areas across Canada. These historic investments will mitigate health and safety risks, halt the loss of nationally significant built heritage and stimulate the economy in communities across the country.

The new dam will not alter the water management strategy for Bobs Lake. Furthermore, throughout the construction of the new dam, plans will accommodate Parks Canada’s water management requirements and residents should not experience any significant change in water levels due to construction.

About Bobs Lake Dam at Bolingbroke

Dams have existed on Bobs Lake at Bolingbroke since at least 1821. In 1870 the dam site was purchased by the Government of Canada in order to enhance the size of the reservoir for the Northern Sector of the Rideau Canal. In 1871 the dam was significantly increased in size and the volume of water in Bobs Lake was raised considerably. The current dam has been in place since 1930 and has seen several major repairs over the course of its operation.

For More Information:

For up-to-date news on infrastructure work along the Rideau Canal, please visit our website: www.pc.gc.ca/rcInfrastructure. If you would like to be added to our community engagement list to receive updates on this project, please e-mail RideauCanal.info@pc.gc.ca and include “Bobs Lake Dam” in the subject heading.