Whenever in the opinion of the commission it is impracticable, because of the height of any dam, or other conditions, to construct a fishway over or around the dam, the commission may, in lieu of the fishway, order the owner of the dam completely to equip, within a specified time, on a site to be selected by the department, a hatchery, together with dwellings for help, traps for the taking of fish, and all other equipment necessary to operate a hatchery station, according to plans and specifications furnished by the department. After such hatchery has been constructed, the department shall operate it without further expense to the owner of the dam except as provided in
Sections 5940 and 5941.