All other barangays in Quezon City are serviced under Service Area West Zone.

The boundary between the Service Areas West and East which coincides generally with the existing MWSS sector boundaries, is drawn, from North to South, as follows:

• The boundary coincides with the Marikina River in the northern part: Quezon City (“QC”) is largely in the Service Area East. San Mateo and Rodriguez are also substantially in the Service Area East. However, due to a small extension of the Rosario settlement (Rodriguez municipality, Service Area East), across the Marikina River, supplied by existing 150 mm mains, the Zone limit departs locally from the sector boundary up to the closest Marikina River’s right bank watershed limit.
• The boundary follows the Marikina River down to the Loyola Subdivision. Rodriguez, San Mateo and Marikina are municipalities substantially in the Service Area East; however, any lands of these municipalities which would be located on the right bank of the Marikina River will be in the Service Area West. The parts of Quezon City located on the left bank of Marikina River are in the Service Area East.
• The boundary cuts west across northern Quezon City before joining the North Central Boundary, close to Pasong Tamo. This departure form the North sector boundary is justified by the AWSOP plan to supply with La Mesa 2 water and the BF and Filinvest Homes subdivisions, which presently receive water pumped by Capitol station from Balara plant.

The following barangays in Quezon City, among others, will be served under the Service Area East:

• Matandang Balara
• Pasong Tamo
• Tandang Sora
• Project 6
• Bagong pag-asa
• Alicia
• Magsaysay

The following barangays, among others, will be served under the Service Area West:

• Talipapa
• Bahay Toro
• Tali Solo

• The boundary is then drawn generally North to South along Mindanao Avenue (QC), Dakilang Lumpo, Pluto, Congressional, EDSA (QC), down to Del Monte Avenue.
• The boundary then follows the course of the San Juan River down to Pasig River.
• The city of Manila is in Service Area West except the left bank of San Juan River and between the Philippine National Railways (“PNR”) railroad tracks, the Manila/Pasay City boundary and the left bank of the Pasig River to South which are in the Service Area East.
• The PNR railroad tracks provides the boundary from Pasig River to South Superhighway/Pres. Quirino Avenue crossing.
• The South Superhighway provides the boundary down to Dilain Creek Bridge. The 220 mm primary mains along the south Superhighway are in the Service Area West, while the 400 mm Pasong Tamo mains are in the Service Area East.
• Part of the Cosmopolitan Subdivision and part of Magallanes Village, both in Makati City located west of the PNR railroad tracks will be included in Service Area West, and the rest of Makati is part of the Service Area East.
• The western and southern boundaries of Taguig from Dilain Creek Bridge provide the boundary up to Laguna Bay.