SHAH ALAM - The construction of flood tunnels, underground water highways and mega rainwater harvesting systems are among the 10 effective recommendations proposed to address the recurring flood problems in the country.
Universiti Putra Malaysia (UPM) Civil Engineering Department senior lecturer Associate Professor Dr Badronnisa Yusuf said while these mega projects could offer significant benefits, they required high costs and detailed studies to ensure functionality and effectiveness.
"One suggestion includes an underground flood diversion tunnel to gradually transfer water from flood-prone areas to safer zones.
"Another is an underground water highway with a dual-function concept, such as Kuala Lumpur’s Smart Tunnel, which serves as a traffic route during dry seasons and a waterway during heavy rains. This helps to alleviate traffic congestion and manage floods," she told Sinar.
Badronnisa also proposed a Mega Sky Funnel system in specific areas to collect and channel rainwater into nearby reservoirs for storage.
"Additionally, the government could construct large retention ponds in strategic locations, where rainwater can be collected and stored before gradually being released into rivers or the sea when water levels recede.
"Nature-based solutions, such as large-scale reforestation, particularly downstream and creating more wetland areas to serve as natural water retention sites, could also reduce flood risks," she added.
UPM Environmental Sustainability and Water Security Centre Senior Fellow Professor Dr Zulkifli Yusop highlighted that building large dams was a suitable mitigation measure to address flooding issues.
"For instance, Kelantan does not have a major dam and its flat terrain makes it difficult to implement effective mitigation measures.
"The state only has small dams, like Pergau Dam, which are insufficient to control water overflow. Large dams could significantly reduce flood impacts," he said.
Zulkifli suggested that flood barriers, like those built along the Golok River in Thailand were appropriate if floods were caused by river overflow.
While this project was ongoing in Malaysia, it had already been completed in Thailand.
As a hydrology expert, he also stressed the importance of efficient pumping systems to manage flooding caused by climate change and rising sea levels.
"Determining the number of pumps requires comprehensive studies and modelling. For example, we need to estimate the volume of water that needs to be pumped out over the next 10 to 20 years based on flood predictions.
"Urban areas near the sea, like Johor, already have pumping systems to channel water into river basins to prevent flooding," he said.
Zulkifli also proposed constructing retention ponds similar to the one at Sungai Johor, which, despite its RM700 million cost, could offer a viable alternative.
"In downstream areas, we could excavate ponds to store rainwater. Existing ponds, such as those in Selangor, could also be utilised for flood control," he said.
Meanwhile, the university's Department of Civil Engineering Faculty of Engineering senior lecturer Dr Balqis Mohamed Rehan said the government should shift from conventional structures, like flood walls along riverbanks, to large reservoirs capable of accommodating heavy rainfall downstream during the Northeast Monsoon.
"The water collected in these reservoirs can be released back into rivers or reused. For instance, Japan’s MAOUDC system comprises massive temporary water storage and underground channels located 22 metres below ground.
"However, such projects require significant funding and extensive time for completion," she said.
Balqis warned that the financial losses caused by floods could exceed the investment needed for flood mitigation projects if authorities fail to act effectively.
INFO - 10 Effective Flood Mitigation Recommendations
- Underground flood diversion tunnels.
- Underground water highways.
- Mega Sky Funnel rainwater harvesting systems.
- Construction of large retention ponds in strategic locations.
- Large-scale reforestation, especially downstream.
- Building dams upstream.
- Efficient pumping systems.
- Flood walls.
- New retention ponds in Kelantan and Terengganu.
- Innovative infrastructure planning, transitioning from traditional flood walls to large reservoirs for heavy rainfall management during the Northeast Monsoon.