Waterfall of the Teotnio before the Construction of the Hydroelectric plant Appears 3.1. Waterfall of the Teotnio before the Construction of the Hydroelectric plant Systems For the Transposition of Fish Has different types of used devices to facilitate the migration of the fish in hydroelectric plants, with intention to diminish the impacts caused for the constructions of the same ones. The generic name of this device in Brazil is, System for Transposition of Fish: STP Existem basically the following types of STP? s: hybrid stairs, elevators, canal locks and other alternative ones. These devices are composites basically, with: entrance, conducting body and exit.

Under the optics of engineering they are destined to facilitate to the reproductive or trfica migration of the fish being successful natural blockages to it or not, by means of the ticket of a volume of water, of sum for ebb tide, favored for the hydraulical gradient, in controlled conditions as for the outflow, levels, speeds, lines of flow and geometry of the structure, in order to take care of to the intrinsic necessities of the fish, without causing its extreme fatigue, (MARTINS, 2004). The migration of the fish occurs downstream in direction and destines upstream it (ascending), and sum for ebb tide (descending). The ascending migration occurs in contrast of the flow of the water course and has the objective to take the fish the reproduction of adequate form. The descending direction occurs in direction the estuary of the river with the objective to look favorable places of feeding, temperature and good physicist-chemistry-biological conditions. So that the STP has success, it is necessary that it has the dynamic movement in the two felt. The STP simplest is the type of stairs with door-sill or step, that sequentially constitutes of a series of reservoirs or spaced out tanks in form of steps. The reservoirs are separate for doors-sill or steps.