Manila Water Company, Inc. (MWCI) is one of the two concessionaires of Metropolitan Waterworks and Sewerage System (MWSS). MWCI provides the eastern portion of Metro Manila as well as the province of Rizal with water supply and wastewater services. The area includes over 6 million people, of which 1.6 million belong to the low-income communities. Around 85% of the population use septic tanks. Many of the septic tanks were deemed improperly designed, constructed and maintained. Up to 58% of the organic load of Metro Manila's receiving bodies of water came from these septic tanks. This has contributed to the poor water quality of Laguna de Bay, Pasig River, and Manila Bay.
In response, MWCI's wastewater management program comprises of:
- septage management, including desludging of septic tanks;
- separate sewer networks; and
- combined sewer-drainage systems.