June_1965 — Page 35

THE

ANGAT RIVER DEVELOPMENT

By

Angel P. Buenaventura

and

Antonio X.

Sison

China

Sea

LUZON

Pacific

50

Ocean

Singa

100

'MILES

HILIPPINE

Sulu

Sea

TINA

DANAO

ACCORDING to studies made by the National Power Corporation (NPC), power requirements in the metropolitan

of Manila growing at the rate of about 12 per cent annually.

area

are

To meet these demands three hydro-electric plants have been built in recent years at Caliraya (36,000 kW), Ambuklao (75,000 kW) and Binga (100,000 kW). In addition several steam plants owned

-To Irrigation

and

operated by the Manila Electric Com- pany, a Filipino private utility, have been put up.

these But despite

increases in generating facilities even greater ex- pansion was necessary and, as a consequence, NPC is now construct- ing its fourth major hydro-electric plant on the island of Luzon.

This project is the Angat River development. It is planned as an integral part of the interconnected system serving the island and prin-

Reservoir

Rockfill Dam

Intake

Tailrace Tunnel

MAIN

POWERHOUSE-

Tailrace tunnel

Switchyard-

Surge tunnel-

ANGAT

Powerhouse Surge Tunnel

Tunnel Diversion Tunnels

Spillway

-Power tunnel

- AUXILIARY

POWERHOUSE

Angat

River

POWERHOUSE DETAIL

Ipo Dam

RIVER

Diversion to Manila

for Water Supply

Figure 1. General plan of development.

Metera

Dike

1000

Plant has installed capacity of 212,000 kW

Far East Architect & Builder June, 1965

cipally the City of Manila and its environs.

Angat River originates in the Sierra Madre mountains. Its watershed area at the project site is 560 square kilometers. The range in monthly flows is from about 10 per cent. to about 480 per cent. of the average flow of 75 cubic meters per second.

Multi-purpose function

The river at present supplies the irrigation and water supply require- ments downstream. During the dry season, water shortage is usually ex- perienced. The river also contributes in no small way to floods during the rainy season which inundate rich agricultural lands in the central plains. of Luzon.

Because of this wide variation of monthly flows throughout the year, the construction of a dam across the river will permit regulation of flow, make available more water during the critical dry season and arrest early flooding during the rainy season. It will also permit the generation of power. Thus, the Angat River Scheme was designed as a multi-purpose project.

The irrigation, water supply and power development of the country are handled by separate agencies of

The the government.

government owned irrigation systems are the re- sponsibility of the Irrigation Ad- ministration while the water supply phase is handled by the National Waterworks and Sewerage Authority (NWSA). NPC takes care of power

Messrs. Angel P. Buenaventura and Antonio X. Sison are respectively pro- jects manager and civil engineer with the Engineering & Development Cor- poration of the Philippines.

69

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