In this paper, we propose a new architecture to read the smart meters which are commonly distributed nowadays in smart cities. In this architecture, public transportation vehicles are utilized as Data Collectors (DCs) that reads these smart meters. Moreover, we target the path planning problem for these DCs given that a limited number of vehicles with a specific storage capacity are able to participate in collecting readings from these meters. We optimize the number of DCs while maintaining their minimum travelling distances and satisfied traffic constraints. We propose a Genetic-based Routing (GR) approach for more optimized solutions. Extensive simulation results are performed to confirm the effectiveness of the proposed approach in comparison to other heuristic approaches.