Millbrook Dam Reconstruction

Otonabee Conservation has embarked upon a major capital  project with the reconstruction of the Millbrook Dam.

The Board of Directors of Otonabee Conservation approved the awarding of a construction contract to Facca Incorporated at it regular meeting, held Thursday, October 19, 2017.

Pictured above is a rendering of the new design for the Millbrook Dam.

ABOUT THE DESIGN

The floor of the spillway has been designed to address geo-technical issues of the site; these design features will not be visible to the viewer as they are below ground and underwater.

The weir will be a u-shaped weir with outside wall dimensions of 5 meters by 16 meters by 5 meters.

The spillway will be 12 meters wide.

The size and water level of the mill pond will remain the same as present and the waterfall sights and sounds will be very similar to existing conditions.

A public walkway over the dam will be installed and the area will be landscaped.

CONSTRUCTION UPDATES

January – February – March, 2018:

The construction firm of Facca Inc. arrived on site to prepare the area for reconstruction. The work involved: the installation of safety fencing, the placing of sheet piling to stabilize the work area, the construction of the water diversion channel and coffer dams, the lowering of the water level in the pond with the water flowing through the diversion channel and the removal of the concrete spillway. This work also necessitated a fish rescue (details about the fish rescue can be found here).

April – May – June:

The wet weather through April has delayed the project by about one month. The excavation work has been completed, and the sub-grade granular material has been placed and compacted. The sheet pile cutoff wall and the mud mat have been installed.

The construction of the spillway will commence after the Victoria Day weekend holiday. This work will carry on until August.

Beginning in mid-August the contractor will begin to remove the sediment from the mill pond. This will take approximately 2 months to complete.

 

Installation of Sheet Piling and Coffer Dam to stabilize the work area.

 

Sheet Piling and granular material was used to create the diversion channel allowing water to flow downstream into Baxter Creek.

 

 

 

The water continues to flow, through the diversion channel, into Baxter Creek. The red, wood-sided building in this photo is the Needler’s Mill.

 

In this photo, the concrete spillway has been removed. The rock wall that you see is the east side of what was the east wing of the spillway. The new spillway will be constructed in this location.

 

Work is being undertaken to form the foundation of the new spillway with the installation of the sheet pile cutoff wall and the mud mat.

 

pouring of the concrete for the new spillway
Pouring of the concrete for the new spillway

 

Onsite construction activity including the use of heavy equipment will continue as the reconstruction activity continues.  The work will occur from Monday to Sunday from 7:00 a.m. to 7:00 p.m.

The final phase of the construction project will involve the removal of the coffer dams and the installation of hardscaping on the earthen embankment of the dam. This phase will also involve the removal of sediment from the pond. The project is expected to be completed by early December, 2018.

PUBLIC SAFETY

The safety of the public ~ residents and visitors to the community ~ is of utmost importance during the construction of the Millbrook Dam. The project will draw the attention and curiosity of the public, and given the inherent dangers of a construction site measures will be taken to keep members of the public away from the site.

The construction site will be fenced, and posted with warning signs, prohibiting public access; only authorized personnel will have access to the site. The security fencing will remain in place throughout the entire construction period. Residents are reminded to stay out of the fenced in area where construction activity will occur.

Please be aware of vehicular activity around the Millbrook Dam and immediate area. Heavy equipment, dump trucks and utility vehicles will be on site and moving within the area throughout the construction period.

Given the nature of the construction activity, the water level in the pond will be lowered by one meter throughout the construction period. The ice will not be safe, so please stay off the ice and away from the water’s edge during the cold weather period.

QUESTIONS?

Otonabee Conservation will provide regular updates throughout the duration of this project, so be sure to check back from time to time.

If you have a question, or an observation to share, you may contact Otonabee Conservation by email at otonabeeca@otonabeeconservation.com

The chronology of the various phases of this project may be found in the Chronology of the Millbrook Dam section.