Intermittent water supply affects 1.3 billion people worldwide, mainly in South Asia, Latin America and Africa. The main cause for this situation is due to lack of maintenance and lack of control of consumption, which greatly increases leaks and NRW. A network with uncontrolled demand cannot be pressurized beyond a few meters of water column. A last solution to recover some pressure in the network is to fall back on intermittent supply by zones. There is great interest worldwide in recovering the 24-hour continuous supply in these networks and restoring the supply pressures to standard values.

The challenge of the 9th Battle Competition is to find the best solution to reverse the situation of a network from intermittent supply to continuous 24×7 supply with enough pressure. The current state and mode of operation of a given pilot network will be the starting point of the battle. Leaks are assumed pinpointed and will be provided as starting data. The demand is satisfied currently through household roof tanks or ground level tanks, which data are given as well. Besides, the total quantity of water available is limited.

Although recovering normal supply conditions is a complex problem, the battle will focus on improving the network infrastructure. It is assumed that the manager has a certain amount of money to invest annually, for a period of five years. A series of possible actions to take are declared, each with an associated cost and a degree of achievement of the objectives. The final decisions taken by participants will be evaluated through a set of key indicators. Finally, the best solution will be the one that maximizes the sum of all these indicators, previously normalized, to obtain a single score per participant.