Lenteng Agung Road Collapse: Traffic Congestion and Ongoing Repairs

A significant road collapse, measuring approximately 3 meters deep and 4 meters long, occurred on Jalan Raya Lenteng Agung Raya towards Depok, South Jakarta, specifically past Gang Empang, on Thursday night (May 28). This incident happened despite road officials having performed asphalt patching earlier that day to address a noticeable subsidence in the road surface. The extensive damage subsequently triggered severe traffic congestion on the affected road on Friday morning (May 29), rendering a portion of the thoroughfare impassable.

The DKI Jakarta Water Resources Agency (SDA) revealed the underlying cause of the road collapse on Jalan Raya Lenteng Agung towards Depok, South Jakarta. The incident is primarily attributed to the deteriorating condition of the “hong,” or underground concrete water channel, which had become fragile and porous over time.

Sartono, Head of the Water Resources Agency’s Jagakarsa Sub-district Unit, stated that his team immediately initiated response efforts following the road collapse on Thursday night (May 28). “The incident occurred last night, and we promptly began handling it. This specific channel is known as the UI connecting channel, leading to the Ciliwung River. The landslide created a hole approximately 3 meters wide, 3 meters high, and about 16 meters long. We are temporarily implementing traffic management measures,” Sartono explained at the site on Friday (May 29).

He further elaborated on the temporary solutions: “We installed steel plates on one side. Originally, there were two lanes, but now only one is operational. We are maximizing efforts to prevent further incidents, which is why we installed the plates. We have also brought in equipment to clear the debris underneath.”

Sartono clarified that the primary cause of the collapse was a “crossing hong,” an approximately 3-meter-wide underground culvert located beneath the road. This aging structure had succumbed to erosion and structural weakening over time. “It turned out the cause was a crossing involving a ‘hong’ roughly 3 meters in size. It’s likely very old, hence its porous state. Fortunately, the falling debris has not obstructed the water flow. Perhaps a third of the ‘hong’ collapsed, but it hasn’t held back the water. The water continues to flow smoothly, though about a third of it is now covered by soil. This will be cleared temporarily,” he added.

Sartono also revealed that prior to the road collapse, both the Water Resources Agency (SDA) and the Bina Marga (Roads Agency) had received reports concerning cracks and an undulating surface on the road. “On Thursday evening, we received the information. For SDA, it was merely a hole on the roadside. However, Bina Marga received reports specifically about the road’s condition. On Thursday morning, we conducted a joint survey. During this survey, Bina Marga took steps to flatten the uneven road surface to prevent vehicles from experiencing bumps,” he stated. He added that patching work had been carried out, and warning signs were put in place. Nevertheless, the road ultimately collapsed that same evening.

Adding to the complex situation, a dump truck belonging to the DKI Jakarta Provincial Government, used for transporting soil, overturned and fell into the sinkhole at the Lenteng Agung collapse site in South Jakarta on Friday afternoon (May 29). This unfortunate incident occurred precisely during the ongoing efforts to address the initial road collapse. The truck’s body obstructed the right lane, which was previously accessible to vehicles. The vehicle plunged into the hole at 11:35 AM WIB. Thanks to the rapid response from emergency personnel, the truck’s body was successfully evacuated and moved from the repair area by 11:50 AM WIB. Following the truck’s removal, traffic flow from Pasar Minggu towards Depok, which had been completely gridlocked, began to slowly resume.

The DKI Jakarta Provincial Water Resources Agency (SDA) is actively managing the road collapse on Jalan Raya Lenteng Agung (towards Depok) in South Jakarta. Permanent repairs are projected to take 2-3 days, involving the installation of a new box culvert to replace the deteriorated “hong.”

“The approximately 3-meter-wide road collapse is suspected to have resulted from damage to the water channel’s construction beneath the road body. This channel is an old infrastructure that has experienced structural degradation, likely exacerbated by the rainy season,” stated Santo, Head of the South Jakarta SDA Sub-agency, in a press release on Friday (May 29). “As an initial response measure, on Friday morning (May 29), the SDA secured the site by installing temporary steel plates to ensure the safety of passing road users and help manage traffic flow,” he added.

Santo elaborated that the permanent repair work would commence at night to minimize the impact on daytime traffic congestion. The currently backfilled area will be re-excavated for the installation of concrete box culverts. “Permanent repairs will begin on Friday night (May 29) to mitigate traffic congestion, as daytime efforts are focused on alleviating existing bottlenecks at the location,” Santo confirmed. During this repair process, the SDA will replace the old structure with a concrete box culvert, measuring 2 meters wide and 16 meters long. “The permanent channel repair will utilize a concrete box culvert, 2 meters wide and 16 meters long, to replace the old construction. The work is estimated to take 2-3 days,” he explained. The DKI Jakarta SDA urged the public to exercise caution when passing the site and adhere to traffic regulations throughout the repair period.

The South Jakarta Water Resources Sub-agency (SDA) recommended a complete closure of Jalan Raya Lenteng Agung access towards Depok for the duration of the road collapse repairs. This full closure is deemed crucial to provide ample space for heavy equipment during the demolition and installation of the new culvert on Friday night (May 29). “Yes, a full closure would be better. It would allow us to work more freely. If not fully closed, we will have to work incrementally,” Santo commented.

Santo further explained that the road damage was triggered by the collapse of an old Armco-type culvert, which was in an advanced state of decay. The SDA plans to replace this aged water channel structure with significantly more robust box culvert material. “The existing structure was indeed Armco. Armco has been there for a very long time, possibly even before I joined. Its condition is very old. We will replace it with a box culvert,” Santo elaborated.

Intensive work and the deployment of heavy equipment were slated to begin after sunset, when traffic volume typically decreases. The SDA aims for the entire road surface to be repaired and fully accessible by tonight, to prevent even worse traffic queues in the future. “I will ensure that the entire road surface can be reopened tonight. So, once it’s open, the box culverts will be in place, leaving only backfilling and compaction,” Santo added. Prior to these major works, SDA officers conducted initial handling by backfilling the hollow sections of the road. Materials like stones and soil were used to compact the affected area, making the road temporarily safer for vehicles. This measure was implemented to help alleviate the traffic congestion around the site. In addition to backfilling, the SDA had also installed temporary steel plates at the precise point of the road collapse.

By Friday afternoon (May 29), the collapsed section of the Lenteng Agung road had been covered with steel plates. What was initially a two-lane closure now saw all lanes reopened and passable to traffic. By 6:45 PM WIB, a variety of vehicles, including motorcycles, private cars, and Transjakarta buses, were observed navigating the previously collapsed area. However, motorists were advised to reduce their speed when crossing the steel plates covering the sinkhole due to a noticeable difference in height between the plates and the road surface. Traffic flow was generally smooth and busy, with minor slowdowns occurring only as drivers traversed the steel plates. After passing this temporary patch, vehicles could resume normal speeds.

DKI Jakarta Vice Governor, Rano Karno, addressed the road collapse incident in Lenteng Agung, South Jakarta, on Thursday night (May 28), expressing concern that similar events could occur in other areas. “My primary concern is that such sinkholes might not be limited to these specific areas. This is due to water seepage, which, only God knows, could happen anywhere in Jakarta,” Rano remarked after attending the Waisak Day celebration at Bundaran HI, Central Jakarta, on Friday (May 29).

Rano disclosed that he learned of the incident on Thursday night and immediately coordinated with the Water Resources Agency (SDA). “However, upon inspection, it was clear that heavy equipment would be necessary, as excavation was unavoidable,” he noted. He commended the temporary solution of covering the collapsed road section with steel plates, which helped restore traffic flow. “Alhamdulillah (Thank God), while it’s not perfect today, it at least helps increase the frequency of travel and prevents further reductions, as covering it with steel plates aids commuters,” he concluded.