[3] The upper (pondage) reservoir located at 7°47′11″N 125°1′25″E / 7.78639°N 125.02361°E / 7.78639; 125.02361 (Pulangi IV Upper Reservoir) diverts water into a power channel which parallels the river until it reaches the lower reservoir (surge pool) at 7°42′56″N 125°1′25″E / 7.71556°N 125.02361°E / 7.71556; 125.02361 (Pulangi IV Hydroelectric Power Plant), 7.5 km (5 mi) to the south.

At the lower reservoir, water is fed to each of the three 85 MW (114,000 hp) Francis turbine-generators via a penstock.

[4] Since operation, the reservoirs associated with the power plant have received an estimated 1,500,000 m3 (1,216 acre⋅ft) of sediment annually.

The siltation rate was almost 1 meter annually and caused the dam's reservoir to work at 50% capacity.

[6] The unexpected siltation threatens safe operation of the dams and power generation, in addition to drastically shortening the predicted operational lifespan of the dam.