Nepisiguit Falls Generating Station Life Extension Project
The Nepisiguit Falls Generating Station (NFGS) is a hydroelectric power generation station located on the Nepisiguit River 20 minutes South of Bathurst. The Station began operation in 1921 and consists of three (3) generating units with a design rating of 3.6 MW each for a total of 10.8 MW. Currently the maximum output is limited to 10.2 MW.
NB Power purchased the Station in 2008 and has continued to maintain and upgrade the operating equipment to current safety and operational standards. The Station operates with seven (7) employees.
NFGS is now over 100 years old and requires several projects to extend its life. All work is typical for a station of this age to continue operating. Five (5) sub projects that have been identified to increase the life expectancy of NFGS for another 50 years are as follows:
- Unit Replacement
- Forebay Bridge Replacement
- Spill Gate Bladders Replacement
- Powerhouse/Gatehouse Structural Repairs
- NFGS By-pass Road
Benefits of Upgrading the Nepisiguit Falls Generating Station (NFGS)
NB Power is planning upgrades to the Nepisiguit Falls Generating Station to extend the life of the plant and put more renewable energy on the grid. This investment is part of a long-term plan to ensure New Brunswickers have clean, reliable energy at competitive prices for generations to come.
- NFGS is located on a natural fish barrier
- NF currently represents approximately 0.42% of the production in the province. This upgrade increase that to 0.56% of the production in the province.
- NFGS currently produces approximately 2% of NB Powers hydro-electric generation. With this upgrade it will increase to 2.65% of the hydro generation.
NB Power will be registering the Environmental Impact Assessment (EIA) for the project this summer. Following the permitting process, work is expected to begin in the summer of 2022.
The station will also require a Fisheries Act Authorization (FAA) from the Department of Fisheries and Oceans (DFO). Details are provided below for the sub projects listed above.
Sub Project Descriptions
Unit Replacement Project
Unit(s) one (1) and two (2) at NFGS were commissioned in 1921 and unit three (3) in 1929. Standard design life for mechanical components in an operational Hydro facility are 50 years, therefore all the units at NFGS are well past their design life. The station has already had to de-rate the generators from 10.8 MW to 10.2 MW due to the aging effect. For this reason, NB Power is looking to upgrade the centerline equipment which includes the turbine and generator. To match the life expectancy of the new centerline equipment balance of plant upgrades will be required for all the mechanical and electrical equipment.
Forebay Bridge Refurbishment Project
The Forebay Bridge’s construction dates back to the 1920s. An inspection in 2020 showed some structural concerns. At that time the bridge was closed to vehicle access and is currently only being used for essential operational activities with mitigating measures in place. NB Power is looking to either refurbish the current bridge or replace the bridge in 2022.
Spill Gate Bladders Replacement Project
NFGS has two rubber bladders. The Sluiceway Bladder was installed in 1999 and is 15ft in diameter and 101ft long. The Forebay Bladder was installed in 2012 and is 4ft in diameter and is 280ft long. Rubber bladders such as the ones at Nepisiguit typically have a design life of 20 to 30 years depending on the use, environment, and manufacturer. NB Power is currently planning to replace the Sluiceway Bladder in 2023. Replacement of this bladder will require a cofferdam. The Forebay Bladder was installed much later than the Sluiceway Bladder and is therefore not expected to require replacement before 2030.
Structural Concrete Repairs Project
NFGS concrete structure is over 100 years old. Overtime all water retaining concrete experiences degradation due to erosion, natural expansion and contraction, and weather exposure. NFGS structural repairs have been an ongoing effort since the station was commissioned and will continue to be in the coming years. None of the structural repairs identified are a safety concern. All repairs are considered part of the maintenance program. Some repairs may need to be completed either with divers or a cofferdam.
NFGS By-pass Road Project
NB Power is looking to block off the current road that passes the station and have the traffic diverted through a bypass road. NB Power would complete this by fencing off the current road passing the station directing traffic away from NFGS and onto the by-pass road. This will allow for continued use of the road without it coming so close to maintenance activities at the station. NB Power is planning on completing this work in the fall of 2021.
Proposed Project Schedule
|Unit Replacement||Unit 1- 2022
Unit 2 & 3 - 2024
|Forebay Bridge Replacement||
|Powerhouse/Gatehouse Structural Repairs||Ongoing for the life of the Station|
|Spill Gate Bladder Replacement||2023 (Sluiceway bladder)
~2030 (Forebay bladder)
Note: Rubber Bladder will be required to be replaced every 20 to 30 years due to material design life