Optimization Strategies for Bi-Weekly Household Waste Collection in Conakry: A Trade-Off between Cost and Operational Regularity

Effective household waste management in developing cities requires optimization approaches adapted to local constraints. This article proposes a methodological framework for bi-weekly collection planning in Conakry, where the territory is divided into two sectors serviced on different days. The study aims to reconcile two often conflicting objectives: minimizing operational costs (total distance traveled) and maximizing operational regularity between early-week and weekend cycles. Regularity is defined as the similarity of operational characteristics (number of vehicles, distances, schedules) between the two sets of routes, aiming to ensure predictable service for users and stable working conditions for collection teams. Six construction heuristics are designed according to different generative logics and compared on Solomon instances adapted to the specifics of Conakry. The results reveal a fundamental trade-off: the most economically effective method (independent route construction) generates the lowest regularity, while the method optimizing regularity leads to significantly higher costs. Hybrid methods offer intermediate trade-offs whose performance varies according to the geographical configuration of collection points and the severity of time constraints. This research provides Conakry’s decision-makers with a decision-making framework for choosing a planning strategy aligned with their operational and financial priorities.