Proposed dams in the Kaliwa River watershed

[4] It is described as "an important wildlife habitat that contains dipterocarp trees, a wide array of birds, mammals, amphibians and reptiles, some of which are threatened and endemic species."

It contains he 180 ha Laiban sub-watershed, a microbasin of the bigger Kaliwa Watershed, nestled in the southeastern portion of the Sierra Madre Mountain Range.

Proposals for the construction of this downstream dam still involves the placement of conveyance tunnels and reservoir areas in the upstream Tanay, Rizal site.

[9][10][11] The ensuing collapse of the Philippine economy, worsened by the political pressure after the assassination of Benigno Aquino, led to slow development of the Laiban dam project until Marcos was forced out of office and into exile by the 1986 People Power Revolution.

[7] In 2009, San Miguel Corporation submitted an unsolicited proposal for the building of a dam in Laiban, but public opinion at the thought of higher water rates led to the project once again being shelved in 2010.

[16] In 2015, two consortia were pre-qualified to bid for the undertaking of the Kaliwa Dam project[17] — the SMC-K Water Consortium, which is a partnership between San Miguel Holdings Corp. and Korea Water Resources Corp.; and the Abeima-Datem Consortium, which is a partnership between Albeinsa Infraestructura Medio Ambiento S.A and Datem Inc.[17] When the project had not moved forward by the time Aquino administration ended, the succeeding Duterte administration decided not to pursue the Kaliwa Low Dam plan.

As a result, only stage one, involving Kaliwa Low Dam its attendant the water supply tunnel, were actually approved for construction during the administration of Benigno Aquino III.

[19][22] Proponents of the dam state that the project would bring various security and tourism benefits, while alleviating the water shortage in Metro Manila.

[23] Excavation works for the dam is scheduled to begin in December 2021, to be done by a joint venture of MWSS and China Energy Engineering Corporation (CEEC).