Designing a decision support tool for strategic waste collection

Waste collection management has seen an increasing interest in the OR community these past years. This is due to the wide range of Capacitated Vehicle Routing Problems (CVRP) studied and the growing trend in studying sustainability-related problems.

For waste collection companies, it can be challenging to identify the type of strategy most suitable for a given situation. On the one hand, the complexity of the state-of-the-art algorithms presented in the literature; on the other hand, the data needed for these algorithms can be challenging to obtain and encode.

In partnership with Alpenluft, a Swiss waste collection consulting company, and the Innosuisse agency supporting R\&D projects, we developed the WasteLogs application, a user-friendly strategic waste collection decision tool. The application offers interfaces allowing the encoding of the collection points, the amounts of waste to collect, and the collection strategy in different features that can be combined to generate a routing for collection vehicles. There are currently three state-of-the-art collection strategies implemented in the tool. Each algorithm minimizes the CO2 emissions through heuristic methods; the user can then identify what collection strategy is the most suitable and extract the information needed to import them into GPS systems. WasteLogs also allows importing existing collection tours to evaluate whether they can be improved.

The major contribution of this tool is the possibility of testing a wide range of scenarios through the granularity of the data the user can input. We present a case study in Swiss municipalities. Each municipality has very different characteristics such as the topology of the road network, the density of the population, type and amount of waste to collect, some areas with restriction on the type of vehicule that can be used for collection, the location of the waste depots,... We show in numerical experiments that based on these information, the best strategy for waste collection varies strongly from one municipality to another, emphazing the need in having decisions tools allowing to test a wide range of setting for the end user.