Wawa Dam

Wawa Dam, also known as Montalban Dam, is a gravity dam constructed over the Marikina River in the municipality of Rodriguez, Rizal, Philippines. The slightly arched dam is situated in the 360 m high Montalban Gorge or Wawa Gorge, a water gap in the Sierra Madre Mountains, east of Manila. Construction of the dam began in 1904, and it became operational in 1909, during the American colonial era, to provide the water needs for Manila.

During World War II, Wawa Dam became the focal point of the battle between the US Army's XI Corps and the Imperial Japanese Army's Shimbu Group. The engagement, also known as the Battle of Wawa Dam saw the opposing sides in a seesaw battle along the Montalban-Antipolo hills from March to May 1945.

Wawa Dam used to be the only source of water for Manila until Angat Dam was built and Wawa was abandoned in 1968. Due to insufficiency of water supply for Metro Manila, there was a strong clamor to reuse the dam. The dam and surrounding area is currently protected as part of the Pamitinan Protected Landscape.

In July 2024, the impounding process of the PhP26.5 billion Upper Wawa Dam project, in San Rafael, Rodriguez, Rizal is undertaken by the Prime Infra and WawaJVCo constructors. The Department of Environment and Natural Resources is tasked to protect the Upper Marikina River Basin Protected Landscape. As part of the Wawa Pumped Storage Water Project, it creates a 400-hectare artificial lake for adequate water supply with a 600-megawatt.