Process analysis and optimization of solid waste haulage in Enugu Metropolis

The present state of solid waste management in Enugu Metropolis constitutes a major environmental challenge to residents of the city. Hence, this study is aimed at assessing solid waste transportation in Enugu Metropolis and optimizing the process for effective resource utilization. Several field datasets on the characteristics as well as geographical locations of the dumpsters were collected for various locations using GPS navigation device and stopwatch. A total of eight waste collection routes were identified, each with distinct characteristics. The results revealed that the haul distances for the eight routes ranged from 2.53 to 11.1 km, accounting for between 16.43 and 50.57% of the collection route. The actual haul time varied from 0.43 to 1.22 h with an average of 0.75 h. Haul equations developed based on regression approach, yielded R² values ranging from 0.69 to 0.94 for different days. After the optimization of the haul routes, new routes were found that resulted to the reduction in travel distances ranging from 0 to 64.4% while haul time would thin down to 7 min and 12.4 min of the original values. Insights provided by this study can be used by policymakers for the effective management of solid waste.