Lenteng Agung Sinkhole: Rapid Water Flow Complicates Repair Efforts

The repair process for the sinkhole in Lenteng Agung, South Jakarta, is ongoing, with strong water flow beneath the road complicating efforts. The affected section has been covered with steel plates to allow vehicle passage, but a hole remains on the shoulder, revealing water and debris flowing beneath the asphalt.

Near the water outlet, internet and electricity poles are being secured with red ropes to prevent collapse. A joint team from the Transportation Department (Dishub), Traffic Police (Polantas), Municipal Police (Satpol PP), and Public Infrastructure Management Unit (PPSU) is on site, with the area strictly cordoned off using police tape, orange barriers, and construction fencing. This has narrowed the available lanes, though previously three lanes were kept open.

Head of Jagakarsa Subdistrict Water Resources Unit (SDA) Sartono explained that the water flow was caused by a buildup upstream after the initial collapse. Repairs downstream have allowed water to resume flowing, but the current rapid flow is due to partially installed box culverts. “Before last night’s work, the hole was large. The water had been held back, but after the collapse, it accumulated above. Now it’s draining slowly,” he said.

Sartono confirmed the water volume is decreasing, with updates from upstream teams. He hopes for favourable weather to aid repairs, stating, “It should recede over time. Hopefully no extreme weather or rain.”

Heavy work is scheduled at night to reduce traffic disruption. “Working during the day would cause significant traffic issues. At night, traffic is lighter, so we work then,” he added.

South Jakarta’s Water Resources Sub-Division (Sudin SDA) aims to restore the main road for normal traffic within three days. “The main road will be cleared in three days—traffic will flow smoothly,” said Sudin SDA Head Santo.

Work is focused on a 10-metre section from upstream to downstream, installing box culverts to channel water from the UI pipeline to Ciliwung River. “Today’s priority is completing this section tonight, with asphalt finishing tomorrow night,” Santo explained.

Full repairs are expected to take two weeks due to manual stone revetment work on the sides, which cannot use prefabricated materials because of underground utilities. “The sides require manual stone placement. We can’t use box culverts there due to existing utilities,” he said.

To expedite the road’s reopening for vehicles, SDA Jakarta Selatan is using