KUALA LUMPUR, Jan 8 — In Kuala Lumpur, where sudden downpours can overwhelm even the best flood mitigation infrastructures, timely alerts are just as critical in keeping the city and its residents safe from severe flooding.

While retaining walls, retention ponds and a state-of-the-art stormwater drain form KL’s first line of defence against floods, a city-wide warning system also complements its overall flood mitigation strategy.

This is where the Early Flood Warning System, managed by the Department of Irrigation and Drainage (JPS) Malaysia, comes into play.

To better understand how the system helps residents stay ahead of floods — and what the public should do when a siren sounds — Malay Mail reached out to JPS Malaysia recently.

Comprising 25 water level telemetry stations spread across metropolitan KL, the system uses real-time monitoring telemetry for round-the-clock, automated tracking of river water levels — overseen by the JPS’ Sungai Klang Basin Office (PLSK).

A close-up of the PWTC water level telemetry station beside Sungai Batu, near the Sentul Fire and Rescue Station along Jalan Tun Razak in KL. — Picture by Yusof Mat Isa
A close-up of the PWTC water level telemetry station beside Sungai Batu, near the Sentul Fire and Rescue Station along Jalan Tun Razak in KL. — Picture by Yusof Mat Isa

Each station is equipped with five standard components: an acoustic public address (PA) speaker, solar panels, a siren telemetry system, warning and danger sensors, and a flood gauge.

Powered by off-grid solar panels, the system can broadcast siren alerts up to two kilometres, depending on local topography, giving rescue authorities and nearby residents a crucial head start to stay ahead of rising waters and evacuate if necessary.

When required, each station’s public announcement speakers can also be remotely activated to broadcast additional instructions from the National Flood Forecasting and Warning Centre (PRABN).

A head start

The early flood warning system uses two distinct siren alerts — warning and danger — which are triggered when rising river levels reach their respective thresholds.

A general view of Sungai Batu, which flows downstream to merge with Sungai Gombak and eventually Sungai Klang near Masjid Jamek. Flood gauges can be seen on the right (in yellow). — Picture by Yusof Mat Isa
A general view of Sungai Batu, which flows downstream to merge with Sungai Gombak and eventually Sungai Klang near Masjid Jamek. Flood gauges can be seen on the right (in yellow). — Picture by Yusof Mat Isa

The siren is also designed to help residents gauge the severity of an emergency through distinct audio cues.

When a siren alert is activated, it is always accompanied by a voice announcement in Bahasa Malaysia to differentiate it from police or ambulance sirens.

Warning siren: continuous tone with a slow tempo and high frequency

This siren alert signals that water levels are rising and could flood low-lying areas along the rivers running through the city.

While the water has not yet reached a critical level requiring immediate evacuation, the public is advised to remain alert and start taking early precautions.

Announcement script: Amaran!! Air sungai telah melebihi aras amaran. Dinasihatkan bersiap sedia untuk berpindah. (Warning!! River water has exceeded the warning level. Residents are advised to prepare for evacuation)

Here are the precautionary steps once this siren activates:

  • Move out: Halt all outdoor activities near a river and head towards a safe location.
  • Remain alert: Know the flood risk level in your area, monitor official announcements (PublicInfoBanjir app, publicinfobanjir.water.gov.my and the JPS’ official Facebook page) and take every early warning seriously.
  • Be prepared: Pack important documents (identity cards, land titles, birth certificates etc.) in a waterproof bag, along with medicines and personal essentials for possible evacuation.

Danger siren: continuous tone with a fast tempo and very high frequency

This siren alert is the highest-level emergency signal, indicating that a flood is imminent or already occurring in low-lying areas, which is no longer safe. Nearby residents must evacuate immediately.

Announcement script: Bahaya!!! Air sungai telah melebihi aras bahaya. Dinasihatkan untuk segera berpindah. (Danger!! River water has exceeded the danger level. Residents are advised to evacuate immediately)

Here are the precautionary steps once this siren activates:

  • Act immediately: Do not wait. Direct your family to leave the house and inform nearby neighbours so they can act as well.
  • Turn off main switches: Switch off electricity and gas before leaving to prevent short circuits or fires.
  • Evacuate: Follow authorities’ instructions to move to a Temporary Evacuation Centre (PPS) or to designated higher ground.

Recommended reading:

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