KBRN, Jakarta: The National Disaster Mitigation Agency (BNPB) has enhanced its early warning system for cold lava floods in the Mount Semeru region of East Java by installing new monitoring sensors.

According to Abdul Muhari, Head of BNPB’s Disaster Data, Information, and Communication Center, the initiative aims to improve preparedness for secondary hazards linked to volcanic eruptions, especially with the rainy season approaching.

“The potential hazards at Mount Semeru include not only hot clouds and volcanic ash, but also cold lava. That’s why the monitoring system must be reinforced,” Abdul said in a statement on Tuesday, September 16, 2025.

Mount Semeru is one of Indonesia’s most active volcanoes and is currently at Level II (Alert) status. Data from the Volcanology and Geological Hazard Mitigation Center (PVMBG) shows the volcano recorded 2,449 eruptions throughout 2025.

To strengthen early warning capabilities, BNPB, supported by the Swiss Government through the Swiss Agency for Development and Cooperation (SDC), has installed four Automatic Rain Gauges (ARGs) and one Automatic Weather Station (AWS).

The ARG sensors were placed at the Mount Sawur Volcano Observation Post, Ranu Kumbolo Station, Besuk Bang Station, and Tawon Songo Station. The AWS sensor was installed at Argosuko Station. “All devices are equipped with solar panels and tele-transmission systems,” Abdul added.

BNPB stated that the new system complements existing monitoring tools from the Meteorology, Climatology, and Geophysics Agency (BMKG) and PVMBG under the Ministry of Energy and Mineral Resources (ESDM).

It enables upstream-to-downstream flow monitoring and strengthens community preparedness in priority villages such as Jugosari, Gondoruso, Pasrujambe, and Kertosari.

The sensor installation was carried out through inter-agency collaboration involving PVMBG, BMKG, and the Lumajang Regency Disaster Mitigation Agency (BPBD).

“With this collaboration, the monitoring and early warning system at Semeru is expected to become more effective, coordinated, and capable of reducing risks for affected residents,” Abdul said.

BNPB noted that cold lava floods struck nine subdistricts in Lumajang in April 2024, causing damage to homes, irrigation systems, and bridges, and resulting in fatalities. “That was a crucial lesson for all of us to truly strengthen the early warning system,” he emphasized.

Mount Semeru also experienced four eruptions on the morning of Sunday, September 14, 2025. The first eruption was recorded at 5:13 a.m. local time, with an ash column reaching approximately 700 meters above the summit, or 4,376 meters above sea level. The ash plume was observed to be white to gray in color, with moderate intensity drifting northward. ***

Translator: Misni Parjiati

Editor: Lasti Martina