Tasks Performed: Special consultant retained to conduct detailed geologic field investigations to evaluate the stability of the spillway and tunnel portal excavations. He was also responsible for the design of the diversion tunnels using the NATM, and directing and supervising the work of the native field geologists and professional engineers assisting with the determination of design parameters.
Duration: 1977 (6 months)
Description: Magat Dam is the largest earth/rock fill dam constructed in the Philippines. The dam is 100-meters-high and has a crest length of over 4,000-meters, and a fill volume of 13-million cubic meters. The river diversion scheme includes two 800-meter-long, 12-meter finished diameter, concrete-lined diversion tunnels. The spillway has a crest length of 170 meters and a chute which is 500-meters-long. Both the diversion tunnels and spillway are designed to pass peak discharges of 30,000-cubic meters per second. The dam is the central feature of the Magat River Multipurpose Project located in Northern Luzon, about 350 kilometers north-east of Manila. The dam and reservoir ensure a year-round supply of water to irrigate 240,000 acres of farm land, and with two crops of rice per year, production is expected to ultimately reach an annual yield of approximately 600,000 tons of rice.