Overview

• Name: South Outardes A5 Dam & Pump Station
• Client: Canadian Dam Association
• Contract Value: CA$ 13.2 million
• Contract Type: Construction Management
• Sector: Infrastructure
• Timeline: April – 2009 – July- 2011
• Location: Cote-Nord, Quebec

Description

The Outardes-A9 Embankment Dam & power station is located on the west bank of the Outardes River, adjacent to Dam No. 1. Four 850 ft (260 m) long, 20 ft (6.1 m) wide penstocks deliver water from the reservoir to each of the power station’s turbines. The power station was commissioned in 1969 and currently has a 785 MW capacity. The power station’s turbines were rehabilitated in 2009 which had increased generation capacity by 56 MW.

South Outardes-A9 Dam was built in conjunction with the Manicouagan-Outardes project and is the northernmost power station on the Outardes River. The South Outardes-A9 Reservoir is impounded by eight different dams. The main dam is Dam No. 1 and is a rock-fill, earthen embankment dam along with Dam No. 2. The six other dams are saddle and auxiliary dams; one is rock and earth-fill, four are earth-fill dikes and one serves as a controlled concrete spillway

South Outardes-A9 Dam, the rising main form of the raw water components of the Outardes River. Stretching 240 m in length and standing almost 40m high, the dam will hold in excess of 14.5 million cubic meters, providing a much-needed supply of water to surrounding communities consisting of 244,000 people.

A cofferdam was constructed upstream to direct the river into the diversion tunnel; none was built downstream because the river’s grade was sufficient. Workers and engineers cleared alluvial material from the riverbed but ran into uplift faults and pot-holes. Around six pot-holes with 10 ft (3.0 m) to 15 ft (4.6 m) diameters and up to 60 ft (18 m) deep had to be excavated, partly by hand. Eventually, those under the dam’s foundation were filled in with concrete.

Falex put together a proposal to CDA providing solutions on which products would best suit the mix design that they were looking for the A9 Dam, Pump Station & Power Station. CDA then approved Falex proposal to supply the concrete admixtures and other required necessary material. Falex successfully provided concrete, specially designed for various applications: Base of intake towers, Pillars, Concrete Spillway.

Additionally, Falex supplied a number of other high-performance products, thereby assuring Outardes Water of the highest quality of this crucial project upon completion.