Srbijavode commissions General Project for regulating flow of Nisava from mouth to border with Bulgaria

The Srbijavode company has commissioned the preparation of a General Project for regulating the flow of the Nisava from the mouth to the border with Bulgaria, i.e. for the preparation of technical documentation for the regulation of this river.

The main objective of the General Project is, as stated, to review the current situation, flood protection, riverbed stability, improve the hydraulic power of the river, the permeability of the river, as well as the fact that it will be the basis for future investments.

As indicated in the tender documentation, field investigation works are particularly important within this work, which are necessary for a comprehensive and precise review of the issue and the results of which should represent the basis for regulation projects.

– Morphological bases are of particular importance for the Nisava, which are very unreliable, because systematic continuous recording of cross-sections of the riverbed has not been carried out for several decades. It must be kept in mind that the scope of geodetic surveys of the minor and major riverbeds would be very large, given the length of the watercourse. Bearing in mind the required scope of geodetic surveys of the riverbed, the time required for their implementation and the relatively high cost of these works, as well as the morphological changes that may occur, the proposed general project would be developed within one year so that upon completion of this project, in which priority sections for regulation would be determined, more detailed surveys of the riverbed on these sections could be undertaken, which would represent the basis for subsequent technical documentation – it was emphasized.

As added, the General Project would strive for maximum rationalization of regulation works. This means that the task of the developer would consist in determining the smallest possible scope of regulation works, but with optimal effects on the watercourse regime, stability of the river route and protection of the coastal areas from floods.

– The main objective of the General Project is to comprehensively consider the hydromorphological, hydraulic and protective characteristics of the Nisava River on the section in question. The project must define conceptual solutions for improving the flood protection system, ensuring the stability of the riverbed and increasing its permeability. This document represents an expert, technical and economic basis for making strategic decisions and initiating future investment cycles – the documentation emphasizes.

As emphasized, when analyzing the current situation, it is important to consider the stability of the banks, whether there is a natural movement of the riverbed or the collapse of the banks, and what material the riverbed is made of.

– All hydrotechnical structures located on the section in question should be listed, described, their condition assessed, whether they are functional or not. If a structure is damaged, a presentation and a proposal for rehabilitation should be provided. When it comes to flood protection along the Nisava, there are structures that have been built, and they are mainly built in cities and settlements along the Nisava. The general design should review the current level of protection, the condition of the facility, but also draw a parallel with the adopted water management strategy, both in urban and rural areas, to define flood zones along the entire section and their impact on infrastructure with an emphasis on road and rail infrastructure. The analysis of the hydraulic power of the river should consider the ability of the riverbed to quickly and efficiently conduct a large amount of water, thereby reducing the risk of flooding. This can be achieved by increasing the permeability of the riverbed, arranging the riverbed for large waters (cleaning the landfill and facilities located there), and possibly deepening the bottom (dredging) – it was specified.

Also, as pointed out, it is necessary to review the situation regarding the bridges located on the section in question and provide a hydraulic picture around the bridges. The final outcome of the General Design must be a high-quality and clear picture of the entire course of the Nisava that synergistically connects all the identified problems with technically feasible solutions.

– All problems, flood zones and critical points must be spatially displayed and matched with the proposed measures (hydrotechnical, urban and administrative). In order to enable phased and economically optimal investment of funds, the designer must conduct a multi-criteria analysis – the documentation indicates.

Bids can be submitted until August 10.

More details (in Serbian) can be found HERE.

JVP Srbijavode Novi Beograd

Srbijavode

Nišava

General Project for regulating the flow of the Nisava from the mouth to the border with Bulgaria