INGENIEUR
Stage 2 works to raise the
existing dam crest from EL45.72
m to EL 56.60m is currently
under construction as shown
in Figure 7. The Labyrinth type
spillway is located at the right
abutment of the heightened
dam.
The Challenges
Figure 2: Existing Mengkuang Dam
Figure 3: Typical Design Section of New Dam
Figure 4: A Upstream View of New Dam Completed At Left Valley
86
VOL
- MARCH 2016
VOL65
55JANUARY
JUNE 2013
The
project
involves
construction of a new dam and
raising of the existing dam. It is
a large scale civil engineering
project with many stakeholders
and involves complex technical,
environmental and social
issues and construction risks.
Engineering solutions have
to overcome the physical
constraints, cost and time overrun.
After construction of the
new dam, water stored at the
existing dam will be transfered
to the new reservoir on the left
valley to enable continuity of
raw water supply to the Sg Dua
water treatment plant (WTP)
throughout the construction
period. The existing reservoir
will be emptied to facilitate
construcion works for raising the
existing dam.
Risk of construction is
high. Any mishap, especially
during foundation excavation
for the new dam will affect the
safety of the existing dam. Any
interruption of raw water supply
from the existing dam will have
serious adverse impact on the
water supply system in Penang.
Ro ck blas ting at the
commercial quarry near the left
abutment of the new dam will
affect the integrity of the new
dam. The risks of damage to the
concrete structures especially
the plastic concrete cut-off wall