Flash flood in Kajang, Selangor earlier this month. — Courtesy of Khidmat Malaysia
ENVIRONMENTAL experts are urging the government to curb any form of development taking place at Kuala Lumpur’s flood retention ponds, as these are critical to the city’s flood defence strategy and integral to its overall flood mitigation.
“It is time to bolster our defences against climate change, as the weather we are witnessing now is unprecedented and unpredictable,” said former National Water Research Institute of Malaysia (Nahrim) director-general Datuk Nor Hisham Mohd Ghazali.
With the volume of rainfall the city was now experiencing in a single day, he said the response capacity of relevant government agencies was severely strained.
Nor Hisham says authorities can no longer blame climate change and need to adapt approaches.“Our city’s water bodies and retention ponds are currently our best defences and must be diligently protected and preserved.
“Let’s not undermine the capacity of ponds such as Batu, Bohol, Bunus and Taman Desa to function effectively.
“These ponds do not operate in isolation as they are part of a comprehensive flood mitigation system that works in concert,” he emphasised.
StarMetro reported on a tender notice by the Federal Territories of Kuala Lumpur Lands and Mines Office (PTGWP), which called for bids to design and upgrade the 63.45ha Bohol flood retention pond in Seputeh for a housing project.
Following that decision, the Attorney General’s Chambers published a notice in the Federal Government Gazette on May 8, announcing the proposed revocation of the land reservation for public purposes under Section 64 (2) of the National Land Code (Act 828) for Lot 35309 measuring 24.79ha.
Nor Hisham said the proposed development threatened to diminish the pond’s capacity to mitigate future floods, evidenced by flash floods in parts of Taman Kinrara in 2021 and 2022.
He said the floods could have been prevented or at least mitigated had the Bohol flood retention pond been properly maintained.
Nor Hisham, formerly director-general of the Drainage and Irrigation Department (DID), said last week’s thunderstorm that caused a rain tree to fall, killing a motorist and trapping three people in their vehicles, illustrated the severe impact of climate change.
“This incident is a stark reminder of the serious implications of climate change and why the city can no longer depend solely on historical data for flood mitigation,” he pointed out.
“We used to rely on statistical data from the past 50 to 100 years, the Average Recurrence Intervals (ARIs), to predict flooding events.
“ARIs help estimate the frequency of events like heavy rainfall or river discharge levels.
“Historically, this data suggested certain events would happen once or twice a year, such as an ARI 100 or ARI 200 event.
“However, as we saw in 2021 when all our rainfall stations in the Klang Valley recorded rainfall exceeding ARI 100, these predictions are no longer reliable,” said Nor Hisham.
“We need to enhance our defences to a level that can withstand such events, as the patterns are evolving and we cannot merely blame climate change.
“We must adapt our approach,” he said.
Abd Rasid warns against the proposed development of the Bohol flood retention pond.
GEC River Care programme manager Dr Kalithasan Kailasam echoed Nor Hisham’s sentiments, stressing that water bodies must remain untouched.
“We need to allow space for rainwater accumulation and avoid overburdening our rivers,” said Kalithasan.
Institute of Geology Malaysia president Abd Rasid Jaapar warned against the proposed development of the Bohol flood retention pond, emphasising the need for careful reassessment of land historically prone to flooding.
“The recent proposal to develop an area that has been gazetted as a flood retention zone, is alarming.
“Such decisions must thoroughly consider the historical context of the area to avoid repeating past mistakes,” Abd Rasid said.
“Federal and state agencies, including DID and DBKL (Kuala Lumpur City Hall) must improve communication and collaborate beyond political differences to ensure that policies on climate change are effectively implemented at the local level,” he added.
