How to Play Barrage: Solo Mode and Leeghwater Expansion

About Barrage, from BoardGameGeek:

In the dystopic 1930s, the industrial revolution pushed the exploitation of fossil-based resources to the limit, and now the only thing powerful enough to quench the thirst for power of the massive machines and of the unstoppable engineering progress is the unlimited hydroelectric energy provided by the rivers. Barrage is a resource management strategic game in which players compete to build their majestic dams, raise them to increase their storing capacity, and deliver all the potential power through pressure tunnels connected to the energy turbines of their powerhouses. Each player represents one of the four international companies who are gathering machinery, innovative patents and brilliant engineers to claim the best locations to collect and exploit the water of a contested Alpine region crossed by rivers. Over five rounds, the players must fulfill power requirements represented by a common competitive power track and meet specific requests of personal contracts. At the same time, by placing a limited number of engineers, they attempt to enhance their machinery to acquire new and more efficient construction actions and to build and activate special unique-effect buildings to forward their own developing strategy.