The present invention is a safe and effective fish ladder for assisting
fish in overcoming dams, especially in the upstream direction. The ladder
comprises a series of relatively vertical open pools, which decrease in
size in the upstream direction, the pools being conveniently spaced apart
a vertical distance which may be easily jumped by the particular fish
species of interest. By being arranged relatively vertically, so that the
downstream perimeter of one pool is substantially within the downstream
perimeter of the pool directly beneath the one pool, the fish ladder does
not need to be long and expensive if the dam to overcome is high. Also, by
being relatively vertical, the ladder may be conveniently built onto
already existing vertical components on the downstream side of a dam, for
example, onto the support structure for the discharge flume for downstream
migrating fish in the apparatus disclosed in U.S. Pat. No. 5,161,913
(Boylan). Or, by being relatively vertical, the ladder of the present
invention may be built even onto the downstream side of the dam itself.
