The interruption in the longitudinal connectivity of the river is the main effect of the barrages built on the Nistru River, which, for its part, limits connection between the upstream and the downstream parts and determines the modification of the upstream part in the accumulation of water at a time when the downstream part is controlled by the operators of the Dniester Hydropower Complex by discharging water through the hydro-technical constructions of the barrages, shows a study commissioned by UNDP Moldova that is quoted by IPN.
Downstream the Dniester Hydropower Complex, the hydrological characteristics decrease. The water volumes decline by 9.2%. The diminution of water supply continues also towards the mouth, where the volumes decrease by 15%. The water supply declines significantly in February – April – by 40%, in April –27%, in February – 18%. In summer, the changes are minor, while in autumn, there are growths of 10–14%.
The large spring water supply sees a decline of about 38% in the maximum volumes downstream and an about 26% decrease in duration and also a delay of about 20-25 days in the manifestation period. The decrease in the spring supply has a direct negative impact on the development of aquatic ecosystems.
Starting with the 1990s, Moldovan and Ukrainian experts have made effort to plan and implement the so-called spring ecological flooding so as to secure sufficient volumes of water in the Nistru River and to guarantee the reproduction of fish and the stability of the Nistru ecosystem.
The study was commissioned by UNDP Moldova and was developed by a team of independent experts at the request of the Ministry of the Environment, with financial support from Sweden.
