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Tension in Vanderhoof rises with the water

Flood warning still in effect for the Nechako River which is expected to rise another 30 centimeters by mid week.
63666vanderhooffloodmeeting1ONLINE
Justus Benckhuysen

Inconsistencies with flow target numbers has caused some heat between Vanderhoof residents and Rio Tinto Alcan.

The smelting company, which manages the Kenny Dam and Skins Lake Spillway and controls the flow of waters into the Nechako, held an information session on their flow forecast Thursday, May 28. As it stands, RTA has a flow target for Vanderhoof of 700 m3/s but so many variables could change the forecast day to day, Justus Benckhuysen, operations coordinator in Vanderhoof said at the meeting.

“Even now today there is a 60 per cent chance of reaching 700 m3/s  and a two per cent chance of reaching 900 m3/s. And 900 m3/s is a big consequence and that’s something we are very aware of,” he said.

As of Monday, June 1 the Nechako River sits at 633 m3/s with an expected rise of 30 centimetres since Thursday by mid week.

“The numbers can go up and down very quickly, but as of right now 30 centimetres is a safe bet,” Benckhuysen said.

During the presentation Benckhuysen spoke about decisions RTA makes daily on whether or not to release more water. He spoke of uncertainties created through variables such as temperature fluctuation, rain fall, climate change and melting snow pack.

“But I still struggle with their math,” Vanderhoof mayor Gerry Thiessen said at the meeting. “To me it has to be consistent. The science and math are there and they should know what they’re doing.”

At one point, an argument sparked between mayor Thiessen and Mike Long, Kitimat RTA representative, about a phone call council received the day before.

“Yesterday morning we were told to prepare for 800 m3/s now it’s gone way down,” councillor Kevin Moutray said at the meeting.

Mr. Benckhuysen stated his correction.

“You asked us if you should prepare, we said if you want to it’s your decision.”

Mayor Thiessen stood up and said, “No no, that’s absolutely incorrect.” Pointing a finger at Mr. Long.

“Mike, you said it’s prudent we go to 800 m3/. You didn’t say it’s up to us, you said it’s prudent we go to 800 m3/s and three hours later it came in at a five per cent chance. You have to stick with the same story because that’s what’s making this community so antsy.”

Councillor Moutray added, “When it comes out three hours later at a five per cent chance it makes us look dumb.”

Mr. Long replied, “The information isn’t simple so there may have been some confusion but, the possibility of 800 m3/s was very clear to me,” Long said.

During the meeting Mr. Benckhuysen also discussed risk management and what RTA’s options are in regards to what they are doing to mitigate the flooding.

“We can maximize how much water we use in Kemano, we’re doing that, we can increase the water to the Nechako, we’re doing that, we also can fill up the reservoir, which of course we’re doing that without spilling…and then there’s overspilling the reservoir which we did in 2007… so why haven’t we done that or planning on doing it? I’m not saying we’re not planning on it, or that we’re planning on it, it’s not a move you make lightly until you absolutely have to,”  Benckhuysen said.

Other messages RTA representatives got across were that they believe in safety first and are trying to mitigate flooding as much as possible while keeping power moving to the smelter at all times. A reoccurring motto was little flooding now means less chance at catastrophe later.

“The reservoir forecast is we’re expecting it to fill up in ten days,” Benckhuysen said during his presentation. “In the ten day forecast does it make sense to…spill more water now and go to 750 m3/s or 775 m3/s? Those are decisions that will be made in the future, I can’t even guess at them right now.”

One community member brought up an idea to make a safety valve like the Skins Lake Spillway on the other end of the reservoir. Mike Long spoke to the topic saying it is possible but, it’s a complicated aspect on the Kemano side, he said.

“Because there is the bypass around the powerhouse, and when you think of a normal powerhouse at BC Hydro where you got a dam and a spillway and generators right out of the dam, ours is very different. We take[the water] through a tunnel, drop it 800 metres down into our generators. We have 1,000 psi of water hitting our generators. We generate more energy per gallon of water then at any other powerhouse in North America. It’s extremely efficient in the way we use the water which is not want you want in this kind of a situation. To bypass that psi is a 20 foot diameter pressure washer and dissipating that energy there are many challenges associated with that…to take water out the other side at 16 kilometres away from the nearest point, dumping it into the river, is not an easy one. It certainly would change the nature of our operation. I don’t think its something that’s going to happen,” Long said.

Another community member asked about the second tunnel RTA is building. Mr. Long said the work on the second tunnel is done and they are now entering the engineering phase.

Senior policy advisor for Cheslatta First Nation, Mike Robertson, challenged the RTA representatives at the Vanderhoof meeting on their graphs in the back of the room. They agreed they were outdated by three days. Mr. Benckhuysen apologized and reiterated the data does change day to day. Mr. Robertson asked what going to 600 m3/s flow on the spillway would mean for communities downstream.

“400 m3/s on the spillway creates 650 m3/s here in Vanderhoof. Going up to 450 m3/s on the spillway is 50 per cent chance right now,” Benckhuysen said.

Acting president of the chamber of Commerce, Joe Von Dollen, stood up for Rio Tinto Alcan in his statements about living in Winnipeg in a place with no flood mitigation.

“In the three years I lived in Morris the area flooded twice. This reservoir has probably saved a lot of flooding for Vanderhoof. Google Morris Manitoba, there is a dyke that goes completely around the town and when it floods it’s an island. They have to close it off. So to sit here and blame Alcan for all the flooding I think is extremely unfair. I think the reservoir has saved you guys from flooding 25 times over the last few years.”

Multiple people had reversely opposite opinions, feeling RTA doesn’t care about flooding people’s homes as long as they have their smelter in operation.

Visit website www.wateroffice.ec.gc.ca for up to date real-time flow information for the Nechako River.

Contact Rio Tinto Alcan at 250-567-5105 for more information. A recording of this notice is available 24-hours in Vanderhoof at 250- 567-5812.