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Statement Regarding Oromocto Incident
April 29 2023, 10:56 AM
As a company that is committed to the safety of every employee and every member of the public, we are deeply troubled by the images that have appeared on social media showing an NB Power vehicle pushing a person involved in the Public Service Alliance of Canada strike in Oromocto today.
This behaviour is truly unacceptable and will not be tolerated by NB Power. No NB Power employees were involved in this incident, but an NB Power vehicle was involved and therefore our reputation is at risk.
The RCMP intervened, the truck was removed from the road and NB Power began an internal investigation immediately. The persons in the vehicle at the time of the incident were an instructor and two students who are part of a lineman training program. The instructor is employed by a private training company, and we have terminated his involvement with NB Power.
All of our contractors are expected to uphold the same safety standards as NB Power. We will continue to do our part to ensure the well-being of our employees and the community members we serve.
How run-of-the-river stations work during the spring freshet
May 1 2018, 13:41 PM
NB Power’s hydro facilities are located along the Saint John River system. They are “run of river” facilities with very little storage capability. Storage is measured in hours, unlike larger facilities like Churchill Falls in Labrador which can store water for months. Water coming from upstream into the headponds must be used for generation at that moment, or must be allowed to bypass the dam. Put simply, the water that flows in must flow out.
The Mactaquac Generating Station at full load passes water through at 80,000 cubic feet per second. Any flow greater than that must pass through the spill gates. In 2018, the Saint John River flows at Mactaquac were more than 300,000 cubic feet per second. As a result, water at Mactaquac was passing through the spillways. At high flows, above plant generating capacity, the water coming in must be released immediately to maintain the proper slope on the headpond to allow the river to flow downstream.
Essentially the river returns to its natural state during high flow events. In order to maintain the natural flow of the river and allow the water to pass the facilities safely, NB Power has very specific operating guidelines.
Water naturally runs downhill. Increased water flow requires there is adequate slope on the river or headpond to continue the natural flow of the river. In order to accomplish this, NB Power lowers the Mactaquac headpond level at the dam to maintain this slope, thus allowing the passage of natural river flow. When the river flow decreases, the headpond level will return to normal levels.
In the lower Saint John River Basin the Reversing Falls in Saint John creates a natural barrier in the river system that is essentially the narrow end of the funnel. With the current river flows being greater than 300,000 cubic feet per second, approximately only half of that water can pass through the falls at low tide. As a result, a bathtub effect is created in the lower basin whereby the water that is not able to pass through the falls backs up and cause flooding. This is compounded during sustained high flows like New Brunswick is currently experiencing.
Higher than average snow fall in North Western New Brunswick and Northern Maine coupled with rain events has resulted in these sustained high flows.
NB Power’s highly trained staff works closely with Riverwatch, the province’s Emergency Measures Organization and communities all along the river during these events.
NB Power is constantly observing and communicating river and station conditions with the goal of operating facilities with the least possible impact on the natural flow of the river while doing everything possible to keep its infrastructure and people safe.
Mactaquac and the Freshet
April 22 2015, 09:36 AM
After the winter that just kept on giving, the signs of spring are welcome as we put away our snow shovels for another season. With temperatures starting to warm up across the province, this is also the time when many New Brunswickers are closely watching rising water levels in the rivers and in some cases, already dealing with flooding
Now that the spring freshet is upon us, NB Power has been hard at work with the New Brunswick Emergency Measures Organization and other local partners monitoring ice conditions, snow pack, precipitation accumulation and weather patterns.
How it works
NB Power operates six run-of-river hydroelectric generating stations across New Brunswick- the largest being Mactaquac. Run of river facilities depend on the constant flow of the river. To generate electricity, the water flowing into the station is directed down and through turbines, providing the energy to spin the generators. Run-of-river stations have no ability to hold back water. All water that comes into the station must go out - especially during the spring freshet when water flows are higher than normal.
Hydro generating stations like Mactaquac contribute energy to our grid year-round, but sometimes during the spring thaw we have more water flowing into our stations than we’re able to generate. When all of the turbines are operating at full capacity in the station, operators open the spill gates to let out this excess water.
Ice Jams
Ice jams on the other hand do hold back water and ice from moving freely downstream. Ice jams have been the cause of major flood events in the past here in New Brunswick, like those in Perth-Andover, Fredericton and St. George.
These jams happen when the ice in the river breaks up, sticks together and hits the bottom of the river. Like an iceberg in the ocean, what we see from land is only the tip of the ice jam in the river. Once the ice jams, it interrupts the natural flow of the river and the water behind it backs up, causing water levels to rise. Some areas of the river are more likely to experience ice jams than others.
Here are a few other factors that can contribute to ice jams:
- Two rivers joining, like the Tobique and Saint John rivers
- Elements like islands, low bridges and sharp bends can narrow or block the path for ice movement
- Thicker ice in the river
- Shallow areas of river
Severe flooding happens when those factors combine with the following:
- Speed and volume of river flow
- Strength of ice cover
- Snow depth
- Precipitation
- How quickly the temperatures rise
Be safe
It is so important for people to stay away from the water and ice near these hydro stations in the spring. Ice may appear to be solid, but is inconsistent due to changing water flows below. Calm water on the river below a hydro station can quickly turn into rapids with a strong undertow.
Watch for warning signs, boom, buoys and barriers around NB Power hydro stations.
Have an idea for a future blog post? Let us know in the comments section below or email us.
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