KUALA LUMPUR, May 16 — The authorities are looking into long-term measures to mitigate flash floods after the recurring disaster struck the city last week.

Mayor Datuk Seri Mhd Amin Nordin Abdul Aziz said there was an urgent need to build an underground waterway big enough to serve as an outlet for water to flow out of the city.

“Heavy rainfall for two or three straight hours guarantee there will be an overflow of water because of our geographical location,” he said yesterday.

“We need a channel to divert the excess water from the city.  A big underground waterway is a feasible solution.”

Mhd Amin said the Department of Irrigation and Drainage needed to bring the proposal up to the federal government as drainage fell under its jurisdiction.

Flash floods struck the city last Thursday, damaging shops and cars.

Natural Resources and Environment Minister Datuk Seri Wan Junaidi Tuanku Jaafar said on Friday the flash floods occurred because the drainage system was incapable of accommodating the rainfall intensity of over 80mm per hour.

Mhd Amin said it was possible to install water pumps in flood hotspots such as Jalan Bangsar, Jalan Pudu and Jalan Semantan, but noted it would not address the underlying problem.

“We installed four water pumps in Jalan Chan Sow Lin last year which solved the woes there, but not flooding in the Klang Valley as a whole,” he said.

“We need a solution which ensures every part of the city is ready to receive continuous rainfall with the intensity of more than 80mm per hour.”

He said the efficiency of existing tunnels, culverts and water retention ponds must also be studied to find the best solution in tackling flash floods.

“Study it, understand its mechanism. Only then we will know if it needs to be upgraded or more of it should be built,” he said.

Mhd Amin said City Hall would present to Federal Territories Minister Datuk Seri Tengku Adnan Mansor a list of problems in Kuala Lumpur and proposed solutions in a fortnight.

He said the River of Life project was not directly aimed at eradicating flash floods, as its main purposes were to cleanse and beautify the river, as well as to develop the areas surrounding it.

“Development here means relocating facilities near the river. It takes years to conduct such a project as cleansing and beautification works could not be done overnight,” he said.

The project might take two to three years to complete.

River of Life is part of City Hall’s  RM4 billion initiative to revitalise dirty rivers in the Klang Valley as part of the transformation plan to enhance Kuala Lumpur’s liveability index.

Mhd Amin agreed with Deputy Prime Minister Datuk Seri  Ahmad Zahid Hamidi’s decision to investigate corruption in mega projects, noting that rapid development was a major contributing factor to flash floods.

“It is important to identify which mega project has undermined the city, and they should face legal action,” he said.

Mhd Amin said the mega projects in the city now were those approved from as far as 10 years ago.

He also said City Hall had only approved three mega projects this year, including Bandar Wawasan and PNB 118, which would be complete in some five to 10 years.