Creating A System For Upstream - Downstream Fish Migration Over The First And The Second Discharge Sills Downstream Of Mănăştur Dam On The Someşul Mic River (Cluj Napoca, Transylvania, Romania)

Abstract

The paper presents a case study that proposes a technical solution to facilitate fish migration upstream the discharge sills located on Someşul Mic River, near the Mănăştur Dam from the Cluj Napoca Town. The proposed solution provides building of a system to facilitate fish migration, placed on the left bank of Someşul Mic River, meant to restore the longitudinal connectivity of Someşul Mic River in front of the Mănăştur Dam discharge sills and to facilitate the access of the migratory fish species to upstream breeding habitats. The proposed migration system is based on using traction of winches and the gravitational fall of water and will lead to the restoration of the longitudinal connection of the Someşul Mic River near the weir selected as case study, and will reconnect a habitat with a length of around one km, that will contribute to insuring of optimal conditions for developing migratory fish species present in the area.

Fish Species Diversity From Someșul Cald River: 50Years After Cascade Dam Constructions

“…Species such as A. bipunctatus, G. obtusirostris, and R. uranoscopus were reported only before dam constructions, while species such as C. elongatoides, R. rutilus, S. labrax, and P. fluviatilis were reported after dam constructions, in this study. Voicu and Merten (2014) mentioned that longitudinal connectivity was also highly affected by hydro-technical facilities downstream of our study area, and habitat restoration is necessary. Other species (C. nasus, B. carpathicus) that live below the trout and grayling ecological zones may be affected in the long term due to longitudinal fragmentation.…”

Principle and Design of Hatch Operation System for Fish Migrating Upstream-Downstream of the Discharge Sill

“…The subject of this article represents a European theme of great topicality and interest; the restoration of the water courses affected by hydromorphological pressures created by the presence of transversal works which lead to the interruption of longitudinal connectivity in rivers, halting fish migration and modifying the flow regime [Kay and Voicu 2013]. The need for longitudinal connectivity of watercourses is an essential condition of the Water Framework Directive approved by the European community and therefore it should be applied to all streams containing migratory species [Voicu and Merten 2014]. Activities such as dam construction for water supply and power generation, channelization for navigation and flood control, land drainage and wetland reclamation for agricultural and urban use, all have a profound impact on the aquatic ecosystem and thus on the natural fish populations.…”