The thesis presents an elaborated solution for wastewater drainage of the Veleniki settlement near Poreč. The work consists of a theoretical, numerical and graphic part, that is, the design documentation. The first, theoretical part of the paper describes the geological and climatological characteristics of the area in question and the location of the intervention in relation to the wider area of Poreština. All the technical elements that have been applied, the method of their installation and maintenance during exploitation are described. At the end of the theoretical part, the topic of rainwater disposal is discussed in cases of non-existent public drainage system. The numerical part consists of the calculation of relevant amounts of waste water, hydraulic and static calculation of the collector. The technical documentation is attached at the end of the work, and includes the condition of the system, the longitudinal profiles of the collectors, the details of the installation of interrupting, inspection and cascade chambers and a representation of the typical trench section. The software of the company Studio ARS d.o.o. called Urbano Canalis 10.3. and the Vargon software package have been used in order to carry out the program. A separate gravity sewer system for waste water drainage has been planned. The main collector is connected to the existing drainage system of the Varvari settlement, agglomeration Poreč - north, with a wastewater treatment plant Poreč - north. The device uses MBR technology, which is described in the theoretical part of the paper. A tentative cost sheet with the associated proof of measures for the project in question has been drawn up and attached.