Gembong Hanung, Jakarta – Flooding and landslides have struck parts of Java amid persistent rainfall, with coastal areas bearing the brunt due to ongoing erosion, and conditions are forecast to deteriorate further.
The Meteorology, Climatology and Geophysics Agency (BMKG) has issued an "alert period" from Jan. 13 to 15 for several regions, particularly West and Central Java, warning of torrential rain, thunderstorms and strong winds.
Several northern coastal areas of Java have already been inundated following heavy downpour over the past few days.
As of Tuesday, six villages and three subdistricts in Demak, Central Java, remained flooded, with water reaching 50 centimeters in depth.
The Demak Disaster Mitigation Agency (BPBD) reported that the worst-hit district of Sayung records at least 520 affected residents across two villages, namely Sayung and Kalisari.
Located south of the Java Sea, the district has long suffered from coastal erosion, making it more vulnerable to flooding from both rain and seawater.
"We've been monitoring the affected areas through our radio and social media channels and conducting dewatering efforts in Kalisari village," said Agus Sukiyono, acting head of Demak BPBD, on Monday.
Several schools in Wonorejo village, in the district of Karangayar, Demak, have been temporarily closed due to floodwaters reaching 70 cm over the past four days, Kompas.com reported.
Last week, floodwaters in neighboring Pekalongan Regency reached up to 80 cm, inundating hundreds of homes. The floods reportedly occurred after heavy rains damaged embankments designed to contain river overflows.
BMKG meteorology deputy Guswanto told The Jakarta Post on Tuesday that prolonged rainfall and high tides could exacerbate floods in Demak and Pekalongan.
"Heavy rain risks worsening current conditions and can disrupt river flow directly into the sea," he said.
Meanwhile, Jepara in Central Java experienced multiple landslides last week. Heavy rains triggered landslides at 18 sites in Tempur village, isolating more than 1,400 households.
As of Tuesday, residents remained cut off from the main road connecting the village to downtown Jepara. Key infrastructures were destroyed, and the village suffered power outages for several days.
Floods and landslides also hit the southern coast of West Java, including the hilly Sukabumi regency, an area prone to tidal flooding.
Prolonged heavy rains last week triggered a landslide that cut off the national road connecting the regency with neighbouring areas.
Guswanto of BMKG said that the agency has flagged landslide risks ahead of forecasted intense rainfall.
"Southern coastal areas of West Java are also vulnerable to high tides, which can worsen flooding," he said.
Beyond climate factors, Susan Herawati, secretary general of the People's Coalition for Fisheries Justice (KIARA), noted that human activity has worsened disaster risks for coastal communities during the rainy season.
She cited rapid industrialization in Demak, where extensive groundwater extraction has altered natural land surfaces.
Since the government approved sea sand extraction in 2023, Susan added, coastal areas may lose ground in coming years.
"Actually, all coastal regions in the country are highly prone to flooding," she said. "Every year, there are villages at risk of sinking."
Source: https://asianews.network/heavy-rain-coastal-erosion-compound-flooding-threats-in-indonesias-java