The objective of this PhD project is to devise an optimization based control notion for water supply systems. A water supply system consists of well feilds, a network of pipes, pumps and a system of valves. It distributes water from sources among the consumers. A control system governs the pumps and valves so that the flow and pressure of water meet certain specifications. Specially, this PhD project will develop control methods that contribute to the reduction of energy consumption and the leakage in the network of pipes. At the same time, the pressure and flow constraints shall be satisfied.