BC Hydro has a lot of dam wildlife to take into consideration.

Reved likes to be useful. So, when its editor overheard some bar chatter about the likelihood of the Revelstoke Dam busting and drowning us all, I decided to get answers to all their dam questions and put their worried, inebriated, hyperbolic minds at ease. Here is Round 2 of Reved’s Dam Questions: Animal Edition.

QUESTION 1: Lake Revelstoke and the Columbia River are misnomers, right?  We call them a lake and river because they’re lake-like and river-like but they’re actually reservoirs?

To quote William Shakespeare, What’s in a name? Lake Revelstoke is the gazetted (that is, official) name for the waterbody although it is a reservoir. And the Columbia River is a river even though portions of it are now reservoirs because of dam construction. And even before the dams were created some portions of the river had different names. For example, Arrow Lakes has always had a separate name even though they are part of the Columbia River.

QUESTION 2 Did (or how did) damming the Columbia change the biological makeup of the waterbody? Were there fish and animal species in the river that aren’t there now? And are there new species that weren’t there before the dam(s)?

Yes, there are many changes that come with damming and regulating a river. Some from the initial dam construction and others from ongoing facility operations and time. Other than the notable loss of salmon from construction of Grand Coulee Dam on the Columbia River in the U.S., as far as we know no fish species disappeared in this area. There are some new fish species introduced by humans, such as Eastern Brook Trout, Tench, Carp, and Yellow Perch. In the lower Columbia River downstream of Hugh L. Keenelsydie Dam, there are also now Walleye and Northern Pike that could eventually make their way farther upstream into the Arrow Lakes system (although they wouldn’t get past Revelstoke Dam) (see question 9).

QUESTION 3 The dam keeps minimal flow levels, so that even if it’s not producing hydro-electricity, the river doesn’t just run dry—that’s because of the fishies?

Revelstoke Dam maintains a minimum flow for ecosystem benefits, especially algae, bugs, and fish.

QUESTION 4  The riverbed around Revelstoke seems really slimy. Is that OK? What’s the BC Hydro take on downstream sliminess?

A slippery riverbed can be from mud or from growth of algae (which can be slimy). Slime, however, is just Nature’s body armour so most of the time we’re OK with it.

QUESTION 4.5 Do you get sliminess on the dam or in the dam in the turbines etc? Is it a problem—how do you deal with it?

Well, a spinning turbine gathers no algae, as it were, so for the most part we don’t have algae growing in the dam. There are a few continually damp walls that have a slow growth of green, but nothing that we can’t handle with a bucket of water and a brush.

Dam Visitor Centre2

QUESTION 5 Does BC Hydro have biologists who study the river system and fish populations?

Yes, we have biologists and other professionals on staff, as well as a small army of contract biologists, who are studying everything from that slimy algae to fish and turtles.

QUESTION 6 Sturgeon. I’m still on this sturgeon obsession from last time. Are there sturgeon in Lake Revelstoke? Or sturgeon in Upper Arrow Lakes? How can we know!

We know there are White Sturgeon in the Arrow Lakes because we have caught them, followed them, still monitor them, and even put young ones in every year. We suspect there are a few still in Lake Revelstoke although there has been no definitive confirmation. Some people have reported seeing sturgeon there from time to time as they will sometimes come to the surface. If you see one, please send us a picture!

QUESTION 7  Outside magazine had a story titled “Goats Scale Dam, World Demands to Know Why….” We at Reved Quarterly demand to know if goats scale our dams?

No goats so far.


QUESTION 8 Dumb question, but does the dam ever suck fish in and then the turbines smush them up?

Not dumb at all, in fact you are asking about what we call “entrainment” whereby fish pass downstream through the dam. At Revelstoke Dam this happens mostly to kokanee and usually the small, young ones. But it is not like there is a strong current at the dam’s water intakes that “suck fish in”, it is more that at certain times of the day and year the behaviour of the fish puts them at greater risk. And fish are usually able to pass through and survive because the turbines at Revelstoke Dam are so huge (just over seven metres in diameter).

QUESTION 9 What about going the other way, I’ve heard of (granted, smaller) dams using fish ladders and even a fish cannon to allow migrating fish upriver. Was anything like that considered for the Mica or Revelstoke dams?

At the time Mica and Revelstoke dams were built, fish passage was not a consideration and was not part of their design. Some smaller hydropower facilities successfully use fish ladders and cannons. For tall dams like these (Revelstoke is 175 metres high and Mica is 244 metres), other systems would have to be used. At some dams, for example, fish are collected downstream and then transported and released above. Μ

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