The project deals with the drainage of sewage in the villages Kráľová pri Senec, Kostolná pri Dunaji and Hrubá Borša and the construction of a common sewage treatment plant in the village Kráľová pri Senec, to which sewage will be drained. The municipalities are located in the southern part of the district of Senec west of Galanta. The area concerned is mostly located in areas with significant natural accumulation of surface and groundwater, i.e. in the protected area of natural water accumulation within the Protected Water Management Area Žitný Island. The project will build a sewage network with a length of 29.86716 km of which 20.87033 km will form a gravitational sewer network and 8.99683 km will form a discharge pipe, including 20 refuelling stations. The number of sewerage turns will be 1438 pcs in length 8,87041 km, the end will be control plastic shafts DN 600/400 with hatch with bearing capacity D400. The average length of sewerage turn is considered at a length of about 6 m. Thus, the total length of the sewerage, including sewerage, will be built in the length of 38,73757 km. The stand is located in the intraviláne and extraviláne of the villages Kráľová near Senec, Kostolná pri Dunaji and Hrubá Borša. Pipelines will be conducted in local roads, state roads, paths and unpaved areas. The area of WWTP with a floor plan 59,80 m x 30,90 m will be situated on the plot parc. reg. ‘C’ 308/28 – other areas. The purpose of the building of biological treatment will be to ensure the treatment of sewage water transported to the WWTP from the pumping station in the village Kráľová pri Senec. From a technological point of view, it is a mechanical-biological WWTP with biological removal of carbon and nitrogen pollution with complete stabilisation of sludge and its mechanical drainage on a centrifuge.