Representatives of the Association of Utility Services Providers in the Republic of Macedonia (ADKOM) visited Sofia at the end of March by invitation of Eng. Ivan Ivanov, President of BWA and Executive Director of Industrial Cluster Underground Infrastructure (ICUI). The delegation included Igor Spasovski, President of ADKOM, Mazlum Leshi, Vice President and Lolita Stoyanovska, Executive Director. Together with Eng. Ivanov, they discussed the situation in the water sector in Macedonia and Bulgaria. The meeting was held at the administrative building of WWTP Kubratovo.
Teodora Todorova, quality control manager at Sofiyska Voda AD acquainted the guests with the scope of activities of the utility, related to the full water cycle coverage, from the water source, through the urban water supply and sewer system, to the discharge of the efluent into the river. She pointed out that Iskar Dam covers about 80% of the water demand of the capital city, Beli Iskar Dam – about 20%, and the river water catchments and wells contribute with less than 1%. The water utility operates 4000 kilometers water supply network, 4 DWTPs, 64 reservoirs, 16 pump stations, 35 water chlorination stations, 1600 km sewer network and WWTP Kubratovo which the guests were able to visit after the meeting. This facility treats more than 400 000 m3 waste water daily, while 100% of the necessary heat for the buildings and 94% of the necessary electric power are being produced by the co-generation system. The digested sludge is utilized by the agriculture as fertilizer. “By drinking water quality Sofia is at one of the first places in Europe with 99.35% conformity by physical-chemical indicators, and 99.80% conformity by microbiological indicators, monitoring being provided at 78 locations in the capital” , Todorova said.
Eng. Ivan Ivanov spoke about the trenchless technologies application in the country comparing them with the classical digging methods. He explained the advantages of the innovations related to the successful rehabilitation of the existing pipelines and building new structures in limited spaces (densely populated urban environment), under automobile routes, railways and river basins, in immediate vicinity to other communications, etc.
Eng. Ivanov paid attention to the ecological advantages of the trenchless technology. He pointed out that the harmful emissions and noise and dust pollutions are minimal during the work due to the smaller building area and less mechanization needed. “People in the urbanized areas no matter moving on foot or by car are not facing troubles as it is the case with traditional digging” Mr. Ivanov said. Last but not least he shared that the contemporary methods are a good economic solution because of the short term of completing the sites and lack of expenditures for subsequent repairs through the years.
“All basic trenchless technologies are being applied in Bulgaria. We produce specialist machinery and equipment”, mentioned Eng. Ivanov. He explained that the company “Building Mechanisation” from Kazanlak has a technological center for new developments. The company is a member of ICUI and has been awarded the prize of the international conference No Dig Berlin 2011. This prize has been the first one awarded to a company from Eastern Europe which is not a branch of a Western European company. Building Mechanisation AD was distinguished in Germany amongst 11 international candidates in its category: completed project in the field of trenchless technologies.
The rehabilitation of the 900 m Ø1220 steel water main with 8 mm wall thickness turned to be quite complicated. The repair of the pipeline located in a densely populated zone with narrow streets and a railway in Moderno Predgradie quarter of Sofia has been carried out with the help of the innovative method “cured in place pipe” (CIPP), or Phoenix. It uses a multi-layer flexible pipe and epoxy resin. Pipes with such a diameter rehabilitated through this technology are quite a few in the world.” Building Mechanization” constructed and produced an inverting machine especially for the realization of the long route.
With the help of the same technology the company repaired 315 m steel pipeline, Ø600, passing under a road junction with heavy traffic in Sofia, without disrupting the traffic.
Phoenix is the most universal and frequently used technology for rehabilitation of worn out pipelines. It is suitable for pipes made of steel, asbestos-cement, cast iron, reinforced concrete, etc. guaranteeing 100% elimination of leaks and improvement of the pipe’s hydraulic characteristics. In addition to this technology, the company uses controlled horizontal drilling, pipe jacking by help of air hammer, microtunelling, spiral-wound pipe lining, etc.
Nikolay Botev, Director Business Development in Raicommerce Construction AD, presented the company to ADKOM representatives, stressing that it has been the contractor of the first project in Bulgaria implementing trenchless technology and has already 19 years of experience in the field. He mentioned a project in Svilengrad, part of the 179 ones which has been completed by the company using highly efficient methods. It has included rehabilitation of 57 km pipelines and construction of WWTP for 20 000 people equivalent. The company is responsible for 30% of the water supply system of Sofia, handling more than 80 000 single calls for repair in the last 12 years.
Botev acquainted the guests with the big project for rehabilitation and construction of 80 km sewer and water supply systems in Kostinbrod. The pipelines have been realized by help of classical methods, similarly to the 20 km pipelines in Byala Slatina where the company is the contractor of WWTP as well.
Raicommerce Construction AD is proud with its 384 completed projects in the field of the infrastructural construction. It has experience and equipment for construction of all kinds of pipelines at different soils. Altogether, the company has built more than 300 000 km water supply systems and 180 000 km sewer systems. It has also a modern asphalt plant producing cold asphalt mix of new generation Ratec which may be laid in any weather conditions.
Before the Macedonian delegation Raicommerce Construction demonstrated a rehabilitation of water pipeline in the Hypodruma quarter in Sofia. The guests were able to see in real time on-site the application of the trenchless technology “horizontal directional drilling” (HDD) where the operation was realized with a specific boring head. The demonstration included three stages – initial drilling, widening to the desired diameter and pulling the pipe.
ADKOM is a non-governmental and non-for-profit organization which unites the utility services in Macedonia. This civil association represents the interests of its members before the central government, aiming at improvement of labour conditions and services offered by them. The association also plays the role of a center of municipal activities, its aim being the provision of prompt and high-quality utility services.
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