Photo by Vince Fedoroff
BOOM GIVES WAY – The barrier at the Whitehorse Rapids Dam has given way to the trees building up along it. The first photo shows workers removing trees from the barrier last Thursday, while the second photo shows the boom up against the dam last Friday.
The gates at the Lewes River control structure were removed last Thursday to allow for the free flow of water, says Yukon Energy president Andrew Hall.
The gates at the Lewes River control structure were removed last Thursday to allow for the free flow of water, says Yukon Energy president Andrew Hall.
Hall said the log boom in front of the Whitehorse Rapids Dam broke last Thursday so staff are having to remove trees that come down through Miles Canyon and end up against the dam.
The boom ended up against the dam, he told the Star Tuesday.
Hall said with no boom, staff in boats are securing the trees that end up against the dam with grapple hooks, then winching them to shore.
They’ve removed 20 truck loads of trees so far, he said.
“There is no reason for Whitehorse residents to be concerned,” Yukon Energy said on its Facebook page late last week.
“This build-up of wood does not impact the integrity of our Whitehorse dam or spillway.
“No debris is entering the hydro dam or causing harm to the hydro units. The dam was actually built with a second line of defence against lake debris – trash racks!”
As the water rises in Marsh Lake, Hall said Tuesday, the flow down the Yukon River increases as well.
The dam is generating electricity using 200 cubic centimetres of water per second, Hall explained.
He said they’re spilling 520 cubic centimetres per second.
Yukon Energy began preparing for the high water in March by opening all of the 30 gates at the Lewes River control structure.
The boat lock-up at the Lewes River bridge has also been opened.
Hall said the level of Marsh Lake has peaked but it may stay at that level for some time.
Yukon Energy staff have sandbagged at the Lewes control structure and the hydro plant at the dam, he said.
Hall said the big unknown is what is in store for rainfall in the coming weeks that could affect water levels.
The Emrgency Coordination Centre released the most recent water levels this morning.
The level of Bennett Lake is currently 14.4 centimetres above the level in the 2007 flood year, though it went down by almost a centimetre in the last day.
Tagish Lake is currently 10 centimetres above the 2007 level, though it has come down .4 of a centimetre in the last day.
Marsh Lake is currently 19.8 centimetres above the 2007 level but has come down half of a centimetre in the last day.
Lake Laberge is currently 41.6 centimetres above the 2007 level but has come down 2.1 centimetres in the last day.
Teslin Lake has dropped by 4.5 feet since it peaked on June 24. It has dropped 12 centimetres in the last 24 hours.
The level of the Yukon River in the Marwell area this morning was just under half a metre above the peak level in 2007.
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Comments (9)
Up 0 Down 0
It's dark in here on Jul 20, 2021 at 3:04 am
Mr. Hall is not concerned with paltry items like a log boom that he doesn't have the resources to deal with anyways. He's a projects oriented kinda guy who would like a rate increase (again) for infrastructure which will probably find it's way to the south end of the runway where it can interfere with airplanes and South access traffic.
"They pay more for power other places", don't ya know.
Up 17 Down 3
My Opinion on Jul 15, 2021 at 4:17 pm
@Grouchy
My understanding was YEC wanted to draw the water down a foot lower in the spring and allow it to hold back a foot more in the fall. If anything this would be advantageous, as it would give a lower starting elevation and allow an overall two feet more water to generate clean energy with. Two feet of water in that system represents a lot of power and starting a foot lower in the spring would be nothing but good.
Up 17 Down 7
Salt on Jul 15, 2021 at 12:47 pm
YEC’s water license has nothing at all to do with the flooding. Nor would it in the future.
Up 4 Down 9
Groucho d'North on Jul 15, 2021 at 11:55 am
@Anie
You may not be aware, but YEC is working to increase the volume of water held in reserve in the southern lakes drainage. Meaning they will hold back water from flowing through the control structures thereby increasing the water level in these now flooding water bodies. YEC's water license stipulates the volumes of water they are permitted to hold back and how much flows through. THIS is what they want to amend so hydro power can be used longer before firing up the diesel generators. Read this : https://www.whitehorsestar.com/News/water-storage-decision-expected-next-month
Up 16 Down 0
Paul Harach on Jul 14, 2021 at 5:03 pm
I believe the numbers in this article are way off. 200 cubic centimetres of water can fit in a glass, it is less than one cup. 520 cubic centimetres is slightly more than 2 cups and slightly more than the amount in a plastic water bottle (500 ml). The numbers quoted should probably be in cubic meters (please correct me if I am wrong). If my math is correct, there is one million times more water being spilled right now and that is creating some very dangerous currents in the river. Be careful when viewing this area or walking near the river as the high water is making the river banks unstable.
Up 16 Down 6
Anie on Jul 14, 2021 at 3:07 pm
Groucho, how would you want the licence amended? It already requires the gates to be opened in the spring.
Up 16 Down 19
Groucho d'North on Jul 14, 2021 at 10:09 am
Mr. Hall neglected to speak about amending their water licence in light of the present flooding situation, I guess he forgot all about that.
Up 44 Down 12
Tinroof on Jul 13, 2021 at 4:08 pm
A large number of those trees were dumped in there by the crew up at the Lewes River (blue) bridge gates. Brilliant!
Up 41 Down 16
BnR on Jul 13, 2021 at 3:33 pm
The whole idea of the boom is to prevent material from going through the spillway and/or into the turbine intakes. They knew all the material was building up, so why didn't they keep the boom clear? If their plan was to just let it break, why didn't they pull the boom prior to its braking? How much does it cost to replace?