INGENIEUR
INGENIEUR
Oroville Dam, with damaged spillway. Picture by William Croyle, California Department of Water Resources( Public Domain, wikimedia. org)
Dams age and deteriorate through ongoing geological and chemical processes. If the foundations and abutments are structurally weak and subject to internal erosion, then dam safety issues can arise. Dam safety deficiencies in the foundations and abutments can include weaknesses( e. g. joints, shear zones, faults) that are susceptible to instability, erosion or liquefaction, and long-term weathering and chemical degradation of materials.
The consequences of a catastrophic dam failure are enormous. At stake are not only lives and property, but communities, their economic well-being and the natural environment.
Malaysia has experienced several dam incidences involving the loss of life and economic losses as follow:
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In October 2013, four illegal squatters who encroached onto the spillway outlet area of the Sultan Abu Bakar Hydro Power Dam drowned when excess water was released from the dam during a monsoon.
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In 1981, Batu Arang Dam, Selangor, an earth fill dam failed due to a classical slip on the upstream slopes during a prolonged wet spell with evidence of the extensive softening of the compacted materials on the upstream slopes.
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Collapse of the spillway at Anak Endau Dam in 1986 during its first over-spilling.
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Damage of Ayer Keroh Dam in November 1993 due to construction at the downstream toe of the dam.
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Collapse of the cofferdam at Paya Peda Dam in 2012 due to over topping by flood waters during construction of the dam.
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Bukit Panchor Dam, Penang, an earth fill dam failed due to a classical slip on the upstream slopes following an extremely wet and then a prolonged dry period in 1970.
With increasing population density the probability of loss of life and property damage is increasing. Vigilance is also necessary because
44 VOL 69 JANUARY-MARCH 2017