At the eighth IMWG session for sewage collection systems and wastewater treatment in Srem, held in Sremska Mitrovica on 25 November 2015, engineers from “Jaroslav Černi” Institute for the Development of Water Resources, presented the first comparative solutions and variants of infrastructure development of wastewater treatment in the Sava Basin in Srem.
During his presentation, Vladimir Jelenković, the chief technologist of the Institute, presented the results of the analysis of site visits and recommended varieties of wastewater treatment, in terms of technology in accordance with the Terms of reference. Considering that Serbia is a signatory of the Danube Convention on the Protection of the Black Sea basin, it means that
a combined approach in water management is applied, which is specified the Water Framework Directive 2000/60/EC. It involves the control of emissions and the establishment of environmental quality standards, using both types of concentration limits: one relates to the quality of water in water-receivers and the second one on the discharged wastewater. Taking into account the amount, dynamics, wastewater quality, two variants of treatment technologies based on low-loaded of activated sludge were proposed in order to have effects beyond 90% purification. One of these facilities is Conventional type in the extended aeration system and the second is with the batch-type reactors with alternate cycle work. The second type of facility was recommended because it is independent of capacity, its integrated treatment means less construction costs and purification process is automatically adjusted to the actual flow of wastewater, fully automatic management and process control.
New proposed variants were further analysed by Mr. Miodrag Popovic in order to assess which variant is best from the standpoint of the technical – technological and economic analysis based on an annual operating and maintenance costs of the facility. Comparative analysis found that, in most cases, more favourable is grouping settlements into a single agglomeration with a common cleaner because of less annual costs comparing to individual sewerage systems. It is further contemplated solution of regional wastewater treatment system Irig – Ruma – Sr.Mitrovica along the existing canal where the collector would be built on the location of the central facility in the City of Sr.Mitrovica. Due to the construction of wastewater infrastructure, favourable topography of settlements, water prices would be lower as well the other costs which this system stands out as the best solution, which should the final economic evaluation confirm in the PFS.
Director of RDA Srem, Milan Marci, gave a very important suggestion that finally adopted solution should have such a level of detail in the PSC with the GP that can be developed in the form of conceptual design. The location requirements for obtaining the largest hydro facilities that comprise this system, i.e. wastewater treatment plants, where a parallel work on the Spatial plan of special purpose wastewater treatment would be realized in 2016. If it is known that the total value of the investment is about 250 million euros, this approach would be involved to ensure the financial resources at this very early stage of design.