The aim of the sectoring-arc routing problem (SARP) is to partition a large region into a given number of smaller sub-regions (sectors) and to build a set of trips in each sector, such that the total duration of the trips is minimized. A graph partition is made to simplify the organization of the activities that must be executed. The SARP arises here in the context of waste collection. A heuristic method is presented, based on the assignment of single tasks to sectors. Sectors are built simultaneously. The heuristic is performed on a set of benchmark problems. Computational results are presented and analysed