Completion of the Central Sewage Treatment Pplant (ÚČOV) at Císařský Island is the largest construction in Prague.
The existing sewage treatment plant at Císařský Island was built in the 1960s. Despite undergoing several reconstructions and expansions, satisfactory capacity and the level of treatment has, due to the speedy development of Prague, never been achieved. Now, the central sewage treatment plant secures the treatment of approximately 95% of the total production of sewage water from the capital city of Prague from almost 1.2 million citizens. The existing sewage treatment plant disposes very successfully the sewage water of undissolved substances and biologically degradable organic pollution; however, the problem lies in the insufficient removal of nitrogen substances. The central sewage treatment plant treats annually 110 million cubic metres of sewage water.
Complicated logistics of concrete supply
In 2004, a decision was made about the modernization of the existing central sewage treatment plant as well as its expansion outside the original area, that is into the area of the former gardening colony at Císařský Island. Construction of the new water pipeline has been under construction since commencement in October 2015, which currently represents the largest concrete construction in Prague. The sole supplier of concrete is TBG METROSTAV.
Approximately 160,000 cc m of concrete has so far been supplied from TBG METROSTAV’s concrete mixing for the construction. High demand for the amount of concrete required intensive planning, supplying and delivering of material for concrete production. The concrete supply mainly comes from the nearby concrete mixing plant Libeň, which is situated by the entrance to the Blanka Tunnel.
In the times of the biggest building employment boom, when there were up to 18 cranes working there and requirement for concrete supply exceeded the production capacity of the concrete mixing plant Libeň, construction was also supplied by the concrete mixing plant Radlice and Rohanský ostrov. It was then common for the concrete to supply up to six pumps (mobile concrete pumps as well as tower and stable pumps), which required thorough logistics in order to prevent confusion and delay. It was necessary to synchronize individual concrete work, monitor the constantly changing communication routes at the building site, adhere to safety measures as well as co-ordinate and place the pumps in such a way so that they wouldn’t collide with other trucks supplying the building site with other materials. The concrete mixing plant Libeň co-ordinated dates and amounts of the planned supply of concrete with individual contractors very thoroughly. The controller then secured, on the bases of the requirements, co-operation with other concrete mixing plants, pumps, relevant number of mixer trucks, control sampling of concrete and a continual supply of individual concrete substances.
Mitigation of impacts on the environment
The biggest part in concrete production is represented by both fine and coarse aggregate. With regards to the restricted capacity for storing sand, aggregate and cement, it was necessary to synchronize the fluency of supplies of these materials. As for the production of concrete for the construction of the central sewage treatment plant, it was necessary to deliver 300,000 tons of aggregate from quarries situated north of Prague. Thanks to the concrete mixing plant’s strategic location on the banks of the Vltava River, it was possible to deliver the aggregate solely by ship. This saved some 10,000 journeys for trucks through the already fully utilized Prague junctions such as the streets of V Holešovičkách or Povltavská. Shipping transport saved almost 1 million km that lorries would have to make on roads and therefore contributed to a reduced wear of roads, more fluent traffic, less dustiness, reduced noise, less accidents and mainly a lesser amount of emissions released into the air.
From the point of view of environmental protection, the location of the concrete mixing plant Libeň TBG METROSTAV within the immediate vicinity of the construction (in the city centre) also proved significant. The mixer trucks with concrete supplying the construction did not burden road traffic in Prague at all. Delivery was secured along the shortest possible route from the concrete mixing plant Libeň, along Holešovice Embankment to Císařský Island, which solely served the needs of the construction.
The most demanding building work has been completed, now comes the installation of technology equipment, which will be followed up by covering up reinforced concrete structures with soil and thus creating an extensive park. Construction should be completed this August.
TBG METROSTAV / Photo: Archive of TBG METROSTAV
The concrete mixing plant Libeň was originally built for supplying the Blanka tunnel complex and is now utilized for yet another large construction – the construction of ÚČOV. It is equipped with a state-of-the-art control system and dust and noise filters. This concrete mixing plant is one of two concrete mixing plants in Prague (along with the concrete mixing plant at Rohanský Island), which has ecologically adjusted transport routes in order to reduce the negative impact of heavy mechanization on the surrounding environment. The concrete mixing plant Libeň is fully equipped for having material delivered to ships. On the banks of the Vltava River, there is a quayside built by the concrete mixing plant where delivered material is unloaded by crane and is then delivered via an underground collector under a cycleway and a four-lane road from the Blanka tunnel to the storage yard within the concrete mixing plant’s complex. This method of a city’s ecological handling of the concrete from concrete mixing plants, which are in the city centre and on the banks of a river, is very popular worldwide; it is similar to the way concrete mixing plants work for in London or Paris for instance.