Solution of a Practical Vehicle Routing Problem for Monitoring Water Distribution Networks

TL;DR

This paper extends the Vehicle Routing Problem to include specific constraints for monitoring water distribution networks, incorporating key collection and return, and proposes models and heuristics validated on real-world data.

Contribution

It introduces a novel vehicle routing problem tailored for water network monitoring, with new constraints and solution methods, including three mathematical models and an Iterated Local Search.

Findings

Proposed models efficiently solve real-world instances.

Iterated Local Search outperforms baseline heuristics.

Validated on both synthetic and real-world data.

Abstract

In this work, we introduce a generalization of the well-known Vehicle Routing Problem for a specific application in the monitoring of a Water Distribution Network (WDN). In this problem, multiple technicians must visit a sequence of nodes in the WDN and perform a series of tests to check the quality of water. Some special nodes (i.e., wells) require technicians to first collect a key from a key center. The key must then be returned to the same key center after the test has been performed, thus introducing precedence constraints and multiple visits in the routes. To solve the problem, three mathematical models and an Iterated Local Search have been implemented. The efficiency of the proposed methods is demonstrated by means of extensive computational tests on randomly created instances, as well as on instances derived from a real-world case study.