If you have lived in Portland long enough, you will end up making a visit to visit the fish hatchery at Bonneville Dam, home to Herman the Sturgeon.  The dams along the Columbia River system have hugely curtailed the once humongous runs of salmonids up and down the river and its tributaries.  Overfishing definitely has a role to play in the depletion of the huge runs, but the hydroelectric – flood control dams have even more hugely impacted the once vast movements of fish.  A recent visit to a small local waterfall brought to light part of the plight of the fish encountering physical obstructions to their journeys. One answer to the problem, fish ladders.