Introduction to water supply. Quality of drinking water. Water demand. Water collection and intake. Case study: the water supply system of major Athens. Aqueducts: general layout, design flows, water transfer by open channels and conduits, special constructions, pumping stations, water tanks. Water distribution networks: design flows, general layout, pressure zones, pressure reducing valves, minimum pressure control. Mathematical modelling of water supply networks: schematisation, computational procedures. Sewer systems: storm, sanitary and combined sewers, general layout, design flows, hydraulic modelling, technology of sewers, wastewater quality issues.