In countries with heavy winters, winter road maintenance, i.e. snow removal, salting etc, is an important problem. In Sweden the government and municipalities together spend close to 0.3 GEUR every year for winter road maintenance. Approximately half of this is snow removal cost, which to mainly is the cost for snowplows, which in turn to a large extent depends on the routing of the snowplows.
The focus of this dissertation is on constructing optimization models and developing solution methods for the Snow Removal Routing Problems with Time Windows. Two cases, after and during snowfall, are studied. We discuss the theoretical aspects of these problems and the considerations that have to be taken when modeling and solving the real-world problem of the Swedish National Road Agency. The presented solution approaches to both cases are implemented and tested on the real-world problem under consideration and on an artificial, generated problem.