Dumai, one of the largest city in Riau Province, has only served 6% of its total population’s needs of water supply, which mean there are only about 16.000 of 280.000 citizen in this city which have been served by Perusahaan Daerah Air Minum of Dumai city with 80 L/s supplying ability and just 50% efficiency. Therefore, water supply infrastructure must be improved to meet the needs of exist…