Education for Sustainable Development: The STEM …
577
3 Flood Simulation for Sg Pinang
Frequent severe floods will have negative impacts on economic productivity, social
equity and political stability, threatening many SDGs. Warming climates with associated SLR and intensified rain events will increase the frequency and intensity of
floods in coastal regions such as Penang. SDG 13 calls for climate actions that mandate taking appropriate measures to mitigate flood damage and to protect the poorer
sectors. It is anticipated that Malaysia will face various degree of SLR and extreme
rainfalls (NAHRIM 2010). The recent extreme flood that affected 80% of Penang
in November 2017 is a wake-up call for climate action. To relate the sustainable
management of storm water at state level, the modelling methodology developed
for storm water management in USM campus has been extended for Penang Island.
The 51 km
2 Sg Pinang catchment (Fig. 5a) is divided into 11 hydrological subcatchments (further subdivided into 18 computational sub-segments). The SWMM
modelling setup involving the links and junctions is shown in Fig. 5b.
Model simulation results indicate that flooding will be intensified by SLR and high
tidal levels, particularly during extreme spring tides accompanied by high rainfalls.
With SLR, a more severe flooding in the future is to be expected for Penang. Ecological soft engineering measures such as flood retention ponds constructed along flood
prone areas to reduce flooding are preferred as they will serve two main functions:
(a) reduce frequency and intensity of floods and (b) increase ecological services. The
design and construction of flood retention ponds along the flood prone Sg Pinang
basin can be assisted by numerical flood simulations, given the anticipated SLR
and increase in precipitation induced by global warming. To mitigate the severity
of flooding along Sg Pinang, a provision of 13 retention ponds, distributed over 13
locations, with a total volume of 30 ha-m is proposed (Fig. 5c). Distributing the retention ponds over a wide area is appropriate for sharing privileges and responsibility,
as suggested by Åstebøl et al. (2004), and is consistent with the overall aspirations
of SDGs. Where Sg Pinang begins, near the confluence between Sg Air Hitam and
Sg Air Terjun (SPJ4 in Fig. 5), provision of retention ponds with a total volume of
4 ha-m could only reduce flood volume by half, suggesting that the retention volume
should be increased if land is available there. Overall, simulation results show that
retention ponds are effective ecological engineering in mitigating flood volume and
in increasing ecological services provided.
Storm water runoff draining into these retention ponds contain pollutants and
nutrients that could lead to water quality problem as in the case of Tasik Harapan
in USM campus. Hence, based on the insights derived from the in-campus study,
mitigation measures that include pollution control and treatment systems installed
on-site at source with periodic sediment dredging are required to maintain the ponds’
hydrological and ecological functions.
577
3 Flood Simulation for Sg Pinang
Frequent severe floods will have negative impacts on economic productivity, social
equity and political stability, threatening many SDGs. Warming climates with associated SLR and intensified rain events will increase the frequency and intensity of
floods in coastal regions such as Penang. SDG 13 calls for climate actions that mandate taking appropriate measures to mitigate flood damage and to protect the poorer
sectors. It is anticipated that Malaysia will face various degree of SLR and extreme
rainfalls (NAHRIM 2010). The recent extreme flood that affected 80% of Penang
in November 2017 is a wake-up call for climate action. To relate the sustainable
management of storm water at state level, the modelling methodology developed
for storm water management in USM campus has been extended for Penang Island.
The 51 km
2 Sg Pinang catchment (Fig. 5a) is divided into 11 hydrological subcatchments (further subdivided into 18 computational sub-segments). The SWMM
modelling setup involving the links and junctions is shown in Fig. 5b.
Model simulation results indicate that flooding will be intensified by SLR and high
tidal levels, particularly during extreme spring tides accompanied by high rainfalls.
With SLR, a more severe flooding in the future is to be expected for Penang. Ecological soft engineering measures such as flood retention ponds constructed along flood
prone areas to reduce flooding are preferred as they will serve two main functions:
(a) reduce frequency and intensity of floods and (b) increase ecological services. The
design and construction of flood retention ponds along the flood prone Sg Pinang
basin can be assisted by numerical flood simulations, given the anticipated SLR
and increase in precipitation induced by global warming. To mitigate the severity
of flooding along Sg Pinang, a provision of 13 retention ponds, distributed over 13
locations, with a total volume of 30 ha-m is proposed (Fig. 5c). Distributing the retention ponds over a wide area is appropriate for sharing privileges and responsibility,
as suggested by Åstebøl et al. (2004), and is consistent with the overall aspirations
of SDGs. Where Sg Pinang begins, near the confluence between Sg Air Hitam and
Sg Air Terjun (SPJ4 in Fig. 5), provision of retention ponds with a total volume of
4 ha-m could only reduce flood volume by half, suggesting that the retention volume
should be increased if land is available there. Overall, simulation results show that
retention ponds are effective ecological engineering in mitigating flood volume and
in increasing ecological services provided.
Storm water runoff draining into these retention ponds contain pollutants and
nutrients that could lead to water quality problem as in the case of Tasik Harapan
in USM campus. Hence, based on the insights derived from the in-campus study,
mitigation measures that include pollution control and treatment systems installed
on-site at source with periodic sediment dredging are required to maintain the ponds’
hydrological and ecological functions.