JOHOR BARU: The Penang government must conduct a review its flood mitigation systems, especially for high-density urban areas, said a hydraulics and hydrology expert from Universiti Teknologi Malaysia (UTM) Prof Dr Sobri Harun.
He said the catastrophic scale of floods in George Town in the weekend was likely an indication that the city's drainage system could not cope with deluge from continuous heavy rainfall.
He said the advent of climate change brought about uncertain weather patterns, and this should be an additional factor that must be taken into account whenever flood mitigation systems are put in place.
"Climate change has affected weather patterns and this can be seen in longer and heavier rainfall in areas which may not have had much rain in the past.
"The changing weather pattern is a factor that must be taken into account by all state-level authorities in their flood mitigation systems.
"From what we have seen in Penang, there is an urgent need for the Penang government to resolve matters in its flood mitigation plans. It must make sure that its current flood mitigation systems are properly-maintained and updated based on changing weather patterns," Sobri told the New Straits Times.
He said the drainage systems in large, densely-populated cities such as George Town must be able to cope with large amounts of rainfall in the event of continuous heavy downpour.
He said although occurrences of heavy rainfall were not frequent, all state governments should have backup systems in the form of water gates or underground water tunnels that will help minimise impact of major cases of floods.
"Water gates and underground water tunnels such as SMART (Stormwater Management And Road Tunnel) in Kuala Lumpur are examples of effective flood mitigation systems.
"The SMART tunnel is based on advanced technology that has helped prevent floods," said Sobri.
He urged the Penang government to address the other issues of land erosion and development projects carried out near rivers, as these issues contributed to floods.
"Land erosion near rivers will cause the river to become narrow, and this brings a risk of floods.
"Under normal procedures, the Department of Drainage and Irrigation (DID) will need to issue a development order to any contractor before earth works are carried for a project.
"This is to ensure there is no risk of soil erosion in the project site. This will also ensure that the contruction will not disrupt the flow of any nearby rivers," said Sobri, who is attached to UTM's Faculty of Civil Engineering.