It makes no sense

Most people intuitively understand that salmon can only swim up a river until they reach an impassable barrier like a steep waterfall. Most people also have come to know that run-of-river hydro projects are built above natural salmon barriers like the aforementioned steep, impassable waterfalls.

Why, then, do some people continue to claim that run-of-river projects harm salmon when salmon and run-of-river projects don’t even come into close contact?

Donald Leung