Bangkok, Thailand – After days of intensive work, city officials announced on Monday that the massive sinkhole on Samsen Road had been filled, a move that stabilised the surface but left questions over demolition, underground repairs and when the road would reopen.
Sinkhole filled but uncertainty remains
City governor Chadchart Sittipunt said crews had completed the filling operation, distributing 1,700 cubic metres of crushed stone on top of a sand-filled foundation. The surface was now firm enough for people to walk on, he said, but warned that authorities must remain cautious. “We must continue to be careful,” Chadchart said at the site.
He added that surrounding buildings, including a police residential block, Vajira Hospital and several commercial properties, had shown no new structural damage since the filling was completed. One exception was the Samsen police station, which sustained severe cracking and was judged beyond repair.
Damaged police station to be demolished
Chadchart said the next major task would be the demolition of the damaged police station. Officials planned to begin dismantling the building within days and expected the process to take about four days. The governor cautioned that the work would be complex because the structure had been built using prestressed concrete techniques with tensioned cables. “We must proceed with extreme care so that no tensioned strands snap,” he said, noting the high safety demands for the demolition team.
Only after the police station was fully removed, Chadchart said, could substantive road rebuilding begin. Local residents were watching closely; many expressed a mix of relief and frustration as they awaited a return to normal traffic.
Road remains closed and commuters affected
Despite the filling operation, officials gave no date for the reopening of Samsen Road, a key artery in the city. The closure continued to force major detours and delays across Bangkok, prompting complaints from commuters and business owners. “We don’t know when we can drive normally again,” one resident said, reflecting the uncertainty felt by people who rely on the route.
Authorities urged patience and said the precautions were necessary. “We are asking people to be patient while we ensure the site is completely safe,” the governor said.
Subsurface inspections focus on subway and utilities
A critical part of the ongoing work involved checking and repairing infrastructure beneath the road. The sinkhole had opened directly above an under-construction Mass Rapid Transit Authority (MRTA) station for the Purple Line, and inspectors examined the MRT tunnels as well as water, sewage and power lines for damage.
The works below the surface were described as particularly delicate. “Safety is the top priority,” Chadchart said, adding that final road restoration would only proceed once all tunnels and utility networks were confirmed to be in working order.
How the collapse happened
The sinkhole formed on September 24 above the MRTA’s construction site for the new Vajira Hospital station. The cavity measured roughly 30 metres by 30 metres and extended about 20 metres deep. MRTA officials said the ground became unstable as soft, waterlogged soil sloughed into the tunnel voids. They cited the combination of heavy construction activity and high groundwater levels as factors that undermined the earth.
Experts continued to investigate the exact sequence of events to prevent similar incidents in future projects.
Impact on residents and the wider city
Residents of the Dusit district endured weeks of disruption as some were forced to leave their homes and businesses found access restricted. Hospitals and municipal services remained active on the response, and city authorities worked to mitigate the social and economic effects of the closure.
The episode underscored vulnerabilities in the infrastructure of a megacity undergoing rapid transit expansion, officials said.
Next steps and outlook
In the coming days, teams planned to carry out the police station demolition, continue the subsurface inspections and begin phased repair work on the road once the site was declared safe. Officials committed to proceeding carefully and updating the public on progress.
When Samsen Road will reopen to traffic remains uncertain. The city administration said it would provide regular briefings and asked residents for understanding as engineers complete the necessary safety checks.
Source: Bangkok Post