The objective of the Budapest Complex Integrated Sewage Disposal project is to solve issues dating back a decade in areas of Budapest and Budaörs that had no access to proper sewage-disposal services in the past. As a result of the comprehensive investment, a new sewage system will be established in formerly unconnected zones, and the collected sewage will be delivered to one of the city’s treatment plants, where it undergoes treatment with the latest technologies. In 2017, the execution of phase V of the BCISD project is one of Colas Alterra’s priorities. The goal is to enable the collection of wastewater in Budaörs, and its transfer to the Budapest Central Sewage Treatment Plant through the South Buda main collector. On order from the city of Budaörs, the works are being performed by the company’s Chief Engineering Unit 12 – the contract was signed in late 2016, and the final completion deadline is the end of 2018. Following a lengthy permitting procedure, actual works commenced in March 2017. During the planning phase, we had to devote special attention to selecting the most cost-efficient equipment and materials to be installed. The project requires us to build over 2,600 linear metres of gravity pipeline from 500- and 600-millimetre glass-reinforced polyester pipes, as well as 1,500 linear metres of pressurised sections from 300- and 400-millimetre pipes of the same material. As part of the scheme, we are also to build a transfer- pump station and several other structures. After the completion of the system, the wastewater currently arriving to the local treatment plant will have to be diverted to the new sewer network, and we will also have to oversee the operational trials. Once the tests are successfully closed, the old plant and the two connected smaller transfer stations will be shut down, allowing sewage to be delivered to the central plant for treatment and subsequent release into the Danube. The demolition of the decommissioned transfer stations also belongs to our scope of works. At most locations, we are relying on conventional open-ditch methods with shoring, but we also needed to engage pipe-jacking technologies at the spot where the pressurised line crosses the Hosszúrét Creek.