The water supply and drainage system of MRT stations are closely related to the station environment and even concerns passenger safety. Everything from air conditioning, sanitary equipment to fire protection equipment all rely on a greatly designed drainage system.
There are two types of water supply systems, the direct water supply system and indirect water supply system. If the water pressure and yield from piped water can satisfy end-equipment needs, it is defined as direct water supply system; conversely, the indirect water supply system. The indirect system includes the gravity tank water supply, pumped water supply and pressure tank water supply. The water supply systems of TIAA MRT stations are used in sanitary equipment, air conditioning system fire protection system and irrigation of plants. Due to different station structure designs, including elevated, plane and underground, water supply measures depend both on the station design and also the water supply condition originating from each local water departments. Of all TIAA MRT stations, pumped water supply is currently used most frequently.
The water drainage systems of general stations include sewage, waste water and rainwater drainage and methods used are gravity drainage, mechanical drainage and indirect drainage. Generally, the gravity drainage method is used for above ground and mechanical drainage is used for underground areas. Sewage include water from toilets, sinks, mop basins, floor pipes, etc. and is usually discharged into the sanitary drain or went through sewage treatment system. Waste water include water from the air conditioning systems, dehumidifiers, tunnels, entrance/exit gutters, drains from mechanical rooms, etc. and is usually gathered in a central pit and then discharged into a public sewer. As for rainwater, there is usually an independent drainage system which the water can be recycled for irrigation or also discharged into the public sewer.