Grand Falls-Windsor Dam Project

grand-falls-damIn October 2016, we started extensive rehabilitation work to modernize the dam at our hydroelectric plant in Grand Falls-Windsor over a three-year period.

The reinforcement of the existing concrete structure and installation of a new inflatable spillway over the dam’s crest aims to stabilize the dam, allow greater control for spilling, better assist fish passage, and make ongoing maintenance activities much safer.

With an electrical generating capacity of 75 MW for the island grid, the generation facility at Grand Falls-Windsor is the largest of three hydroelectric facilities on the Exploits system. The main purpose of the dam is to divert water to the power canal.

Upgrading the dam is essential in terms of ensuring generation supply and reliable service for our customers.

New inflatable spillway
The dam, which extends across the Exploits River, currently uses timber flashboards to increase pond elevation for additional generation and fish passage. These flashboards need to be replaced often, which can be challenging and dangerous work.

Designed to improve the ability to adjust water flows and levels for power production, fish passage, and safety, the inflatable overflow spillway—the first of its kind in our province—will replace the flashboards and allow greater spill capacity and control.

It will be installed in three sections that can control flows independently along the dam, making it easier to control ice and other debris which could impact power generation.

Other work
The project will also include the creation of a single lane vehicle bridge and a pedestrian bridge to provide safe access during construction and future maintenance activities.

Construction activities are planned to be completed in various phases over a three-year period during which the Grand Falls generating facility and dam will continue to function as per current operating and water management practices.

Impact on the Atlantic salmon run
As an active steward in the development of the Atlantic salmon run on the Exploits River, we ensure you that migration patterns will not be hampered by our construction activities.