The Angat Watershed Forest Reserve is a conservation area that protects the drainage basin in the southern Sierra Madre range north of Metro Manila in the Philippines where surface water empties into the Angat River and its distributaries. It is spread over an area of in the eastern portion of Bulacan and northern Rizal province at an altitude of between . The conservation area also extends to the provinces of Nueva Ecija and Quezon and is centered on an artificial lake created by the Angat Dam which, together with the Ipo Dam located downstream, supply 97% of the water requirement of Metro Manila via an aqueduct system to the La Mesa Dam and Reservoir and the Balara Filtration Plant in Quezon City. The Angat Dam and Reservoir is also a major source of hydroelectricity for Metro Manila and surrounding provinces, contributing some 200 megawatts to the Luzon grid. The watershed is a popular birdwatching site and is a biodiversity hotspot containing most of the remaining closed-canopy forests in Central Luzon. History The Angat Watershed was first gazetted on July 26, 1904 as the Angat River Reserve through Executive Order No. 33 signed by Civil Governor Luke Edward Wright. It set aside the Angat River in the municipality of Norzagaray bordering Mounts Salacot, Balugan and Sulip in the Sierra Madre range and including the Bulagao and Bitbit creeks for purposes of the development of water power from the river. On March 10, 1927 through Proclamation No. 71 signed by Governor-General Leonard Wood, the Angat Watershed Forest Reserve was established covering portions of the municipalities of Montalban, San José del Monte, Norzagaray, Angat, San Rafael, San Miguel, Peñaranda and Infanta in the provinces of Rizal, Bulacan, Nueva Ecija and Tayabas, with the administration and control placed under the Department of Agriculture and Natural Resources. At about this time, the Metropolitan Water District (now Metropolitan Waterworks and Sewerage System) started construction on the Angat–Novaliches Water System including the Ipo Dam located within the reserve, which was completed in 1939 and inaugurated in 1940. On December 4, 1965, with the construction of the Angat Hydroelectric Dam within the protected area, President Diosdado Macapagal signed Proclamation No. 505 transferring the administration of the whole reserve to the National Power Corporation. On April 30, 1968, of land surrounding the Ipo Dam was declared as a separate forest range and watershed management pilot project reserve through Proclamation