The main hydraulic effect is the discharge of the collection basin to a stationary
reservoir instead of a stream bed. Therefore, an instant change will start downstream;
downstream of a stream dries partially or totally whenever the reservoir begins to
accumulate water. During this temporary or periodically repeating time interval, the
hydrological balance can collapse; Irreversable death, disapearance and structural
jumps are observed in the water depandent ecosystem. Decay of dead flora and
fauna in the new coming water body speeds up. So, upstream water flows polluted,
without oxygen in deeper parts, dark coloured for a long time and usually smells
rotten because of sulphurous hyrogen disposal. Although after this process the
stream forms a new and healty ecosystem in this part of it, neither this new aqua
balance nor the terrestrial ecosystem and even the sea environment that the stream
joins the sea have the chance to join their previous health.