Hypothetical: Glenmore Dam Fish Ladder

[threepwood]

Humor me in a thought experiment.

 

I recalled today, while watching salmon leap up the waterfall in Katmai, AK, learning about fish that, when they encounter a dam during their spawning migration, often leap against it trying to get past. I also dimly recall seeing someone post about seeing the fish do this at Glenmore Dam. We also know that the lower Elbow is important spawning territory for Bow River fish.

 

Theoretically, if some sort of fish passage were built at Glenmore (and let's leave aside speculation as to the budgetary and engineering feasibility of this), would it materially affect fish populations in the lower Bow and the Elbow below the Falls? It seems to me that such access might give access to great deal more spawning habitat, although I suppose that juvenile fish descending to the Bow would suffer a good bit of predation in the reservoir.

 

Are there ecological consequences I'm not considering? I know dam removal, in general, is probably better for watershed health but that's not really an option here.

 

 

[Dangus]

My first thought is that there is more than enough room for the population. It's not a salmon run with millions of spawning pairs. I just wish the elbow had a more

Natural flow.

Probably let BC chime in on this one.

[jpinkster]

I'd rather see one on the Oldman. There are some monster bulls below the dam that are cut off permanently from spawning habitat upstream. Be nice to get those fish back into the rotation.

[Dangus]

Ya jp, bulls have a wild range as well. There are some radiotelemetry studies on the koocanusa bulls and some individuals used most of the Tribs at one point or another while some just stuck to one.

[jpinkster]

Ya jp, bulls have a wild range as well. There are some radiotelemetry studies on the koocanusa bulls and some individuals used most of the Tribs at one point or another while some just stuck to one.

I remember talking to someone about tagged bulls on the Oldman system. They've seen the same fish in the upper Castle and the upper Oldman within a few years of each other.

[scel]

Are there ecological consequences I'm not considering? I know dam removal, in general, is probably better for watershed health but that's not really an option here.

 

Dams are a Catch-22. On one hand, they cut off habitat from fish.

 

On the other hand, something especially important for trout populations, a bottom fed outlet provides cool oxygenated water with potentially more stable flow.

 

A final thing to consider is how dams create somewhat protected habitats. Adding a fish ladder on the Oldman would help the bull trout move around, but it would also allow the rainbow trout to move around (for example). I know there is already considerably cross-breeding, but there is still a fairly good population of mostly cutthroat trout.

[Jayhad]

I don't think this is a feasible solution to a problem that I'm not sure even exists.

 

I say that because I most would state that the Bow is doing great as a fishery.

The size and amount of fish in that river are ridiculous.

A project with such a large price tag might not be using monies in the best place, if this was to happen I would much rather see this cash go into enforcement.

[muha]

Problem does exist, fish do congregate below dam during spawn in good numbers. Bet that number would be a lot higher if suffiecent water level was reached during spawn period.

 

I have only witnessed brown trout spawn as I don't visit these waters during rainbow spawn.