I recently watched DamNation [1] and was quite surprised at the shear number of dams located in the United States. The film claims that most have outlived their purpose. I can't recall the exact cost stated per fish to divert them around dams or raise them in a hatchery, but it was fairly high. The film's production quality was quite high and was fairly eye opening.
While doing a little googling, I found an article [2] claiming $7 million in fish ladder work after structural damage forced a reduction in water level. So perhaps this solution could be cost effective or quickly put in place in case damage occurs just before a run.
While doing a little googling, I found an article [2] claiming $7 million in fish ladder work after structural damage forced a reduction in water level. So perhaps this solution could be cost effective or quickly put in place in case damage occurs just before a run.
[1] http://damnationfilm.com/ [2] http://www.columbian.com/news/2014/apr/12/crack-in-dam-force...