THE upper deck of Stormwater Management and Road Tunnel (Smart), which caters to traffic from the city centre towards Seremban, will be opened today. 

Smart chief operating officer Mohd Fuad Kamal Ariffin said the lower deck for traffic from Sungei Besi towards the city centre will be opened in phases as soon as restoration works are completed and approval from the Malaysian Highway Authority   is obtained.

"Restoration works are now in full swing with 60 workers working around the clock to clean the tunnel. The removal of water from the tunnel began on Thursday, followed by cleaning works on the upper and lower decks.

"Cleaning works such as getting rid of sludge, rubbish and the replacement of damaged emergency exit signs as well as traffic signs are 50 per cent completed," he said during a press conference at Smart headquarters yesterday.

Systems testing and the restoration of motorway tunnel was also being carried out at press time.

The closure of Smart tunnel after a  downpour on Wednesday afternoon had spared the Smart flood mitigated areas covering Masjid Jamek, Leboh Ampang, Jalan Melaka  and Dataran Merdeka from flooding.

"Our quick response to the surging water  at the confluence of Ampang and Klang rivers has once again saved the critical commercial areas in the city.

"The tunnel systems in Smart were in optimum working condition as proved by its efficient functioning on that day," said Mohd Fuad.

The Smart stormwater mitigation system, said Mohd Fuad, was activated at 2.40pm after receiving a high-level Mode 3 alert from the Selangor Irrigation and Drainage Department due to rising water level at the rivers.

A Mode 3 warning dictates that the motorway tunnel be closed to public to allow passage for excessive water from the rivers, which flows to the Kampung Berembang pond, to be channelled to the Taman Desa attenuation pond via the Smart floodwater bypass tunnel.

The Smart motorway control room reacted immediately but the situation had escalated to Mode 4 which indicated the need for the entire motorway tunnel be filled to its maximum water transference capacity due to the rain volume and intensity.

"Once we received the signal to close the tunnel, the Smart Ronda team was deployed to stop vehicles from entering the tunnel.

"All vehicles in the tunnel were also evacuated. At 4pm, it was completely closed and water from the Kampung Berembang pond was released into the tunnel.

"In just 45 minutes, three million cubic metres of water filled the tunnel and it reached the ceiling height of the upper deck. The next day, we got the green light from the department to start restoration work," said Mohd Fuad.

The water contained in the Smart tunnel, he said, took six hours to be discharged to the Taman Desa attenuation pond.

The Smart flood mitigation system, said Mohd Fuad, had saved the city centre from eight major potential floods in the last five years.

"We have taken note that areas in Kajang, Setapak, Salak Selatan, Bandar Sri Permaisuri, Ampang, Kepong, Bandar Tun Razak, Pantai Dalam, Sungai Besi, Jalan Ipoh and Jalan Tun Razak were affected but these do not fall under the jurisdiction of Smart flood mitigation system," he said.