INGENIEUR
INGENIEUR
Figure 12 : Overall view of Murum project area : Main dam ( background ); Diversion outlet ( foreground )
Spillway
A 54m wide stepped chute spillway of the Murum HEP was incorporated into the downstream of the dam body and designed for the Probable Maximum Flood ( PMF ) event with a discharge capacity of 2,160m 3 / s . It is currently the world ’ s tallest stepped chute spillway designed to carry any overflow safely downriver , terminating in flip buckets , which further dissipate the water energy before ending in a plunge pool ( see Figure 14 and Figure 15 ). The chute step dimensions are 1m high and 0.85m wide . A bridge , with three piers , crosses the spillway directly above the ogee crest . This type of spillway is designed to massively reduce the amount of kinetic energy passed into the river below and equipped with aeration slots to aerate the flow to reduce the possibility of cavitation occurring in the spillway structure especially during the high flow ( high velocity ) periods .
Murum Spillway |
Type |
Ungated Overflow Crest |
Elevation of weir |
540m |
Width of weir |
54m |
Discharge capacity |
2,160m 3 / s |
Figure 13 : Longitudinal section of power tunnel
Figure 14 : View of the flip bucket and plunge pool in the river downstream of the spillway construction
22 VOL 67 JULY-SEPTEMBER 2016