Operational Modes of The Smart Tunnel
MODE 1
When weather is fair with little or no rain and traffic is allowed in the tunnel
MODE 2
- Activated when moderate rainfalls and the flow rate recorded at the confluence of upper Sg. Klang/Sg. Ampang (L4 flow station) is 70-150 m3/s. Only 50 m3/s is allowed to flow downstream
- Excess flood water will be diverted to SMART storages and only the lower drains of tunnel will be used to convey flood flow to the Desa attenuation pond
- Road tunnel will still be opened to traffic
MODE 3
- Activated when major storm event occurs and flood model forecasts a flow rate of 150 m3/s or more at L4
- Traffice will be evacuated from the road tunnel. This normally takes about one hour. Only 10 m3/s is allowed to flow downstream
- If heavy rain storm stops early or due to some specific circumstances, then the traffic tunnel will not be flooded
- Road tunnel will be re-opened to traffic within 2-8 hours after closure
MODE 4
- Activated if heavy rain storm prolongs, usually will be confirmed 1-2 hour after Mode 3 is declared
- Road tunnel will be used for passage of flood after traffic evacuation completed. Only 10 m3/s is allowed to flow downstream
- Road tunnel will be re-opened within 4 days of closure