Good news, I can assure you that climate impact was in fact heavily analyzed, and removing these dams is in the net, a huge win.
So no need for the off the cuff no actual knowledge of the situation snark anymore, isn't that great?
Ecosystem maintenance is part of Earth's homeostasis, and restoring salmon can have major positive environmental effects (increased nutrients upstream, increased food stocks in the ocean, more really available salmon for fishing, etc.)
Dams like this produce little energy, require dredging and maintenance, pose safety risks if they aren't well maintained.
It is, but more from the point of view of the idea that the climate changing will affect things everywhere, and we should prevent that, rather than every action we take should improve the lot of a local habitat.
1. Functional - all the complex interactions and feedback loops that make this planet habitable and comfortable for humanity.
2. Entertainment - look at all those beautiful colors, watch all these creatures frolicking (and ignore when they try to brutally slaughter each other).
The climate crisis threatens both, but it makes sense to focus on the first one first. Yes, it's human-centric, but who-else-centric should it be instead? There's hardly a point in preserving some wildlife if we erase ourselves from the universe in the process.
(At least, I haven't heard any convincing argument made by alien conservationists or future intelligent time-traveling beings that would arise on Earth after us.)
3. Restoring species of commercial importance.
In reality that probably the number 1 reason, as unfortunate as that might be.
I propose that perhaps we do know enough, and the problem is that at social / economic level, we fail to prioritize what needs to be done.
We could quibble about the first part (for one, species are disappearing faster than we can study them, so there is really no way to be sure we know fuck all about how things work), but the second part is clear. We aren't prioritizing anything but economic growth. We can't even conscience using less energy, like e.g. the amount of energy (per capita) our parents or grandparents used. Like leaf blowers. FFS, unless you are a lawn care service, most people could get by with raking.
To survive as society, we need lots of trees growing as fast as possible to fixate CO2 from the air and clean our mess. Ok?
Trees need nitrogen to grow, but this conifer forests lack typically nitrogen so the tree's grow is stunted.
In fact this ecosystems work because there is a major and main external source of nitrogen: The Sea
And more precisely, Salmon migration
The majority of the nitrogen stored in this wild areas came from the salmons. How do we know it? Ecology research.
So, protecting salmon (= removing CO2 from the air) is suddenly a very important issue for us and definitely not a caprice, or something to joke about it.
Unless you're going to then burry all the wood that won't come close to enough. The mass of carbon in oil and in the air is far too much to make up with tree planting.
Also, society can definitely survive a couple of degrees of heating. Though it might not be that pleasant for many.
"Some help" is better than "no help at all", and we need a lot of help currently so, what If --we try-- at least?. We could buy some very precious time. If all that we need is to eliminate some old dams, this is a solution that we can afford.
> Society can definitely survive a couple of degrees of heating
We will know the answer to this question in a few years.
I suspect planting trees will very rarely be the answer (judging by some back of the envelope calculations), while making low regulation nuclear power plants or researching energy storage mechanisms will often be.
In reality though I suspect that this dam is not economically viable to update all of the infrastructure.