Siriphong, Deputy Minister of Transport, apologized for the water leakage into the Purple Line South metro tunnel construction site, assuring strict oversight and problem resolution at every stage. He revealed the road subsidence increased by only 8 cm in one day and expects the leak to be sealed within 7-12 days.
At 14:30 on 10 July 2026 at Wongwian Yai, Deputy Transport Minister Siriphong Angkasakulkit spoke after inspecting the water leakage into the Purple Line South metro tunnel construction between Tao Poon and Rat Burana near Wongwian Yai. He said road subsidence is improving; after a 20 cm subsidence yesterday, the total reached 28 cm today with only an 8 cm increase in one day, which he considers a good sign. Today's subsidence was not continuous as yesterday but occurred in intervals, indicating partial success in sealing some tunnel gaps.
Siriphong added that the team has increased machinery to accelerate sealing gaps. The Bangkok Metropolitan Administration and MRTA coordinated to remove a footbridge to facilitate repairs. Surrounding buildings have not leaned further since yesterday, and officials monitor the site every 30 minutes.
Regarding construction standards, the contractor follows engineering manuals and standards. Siriphong believes the incident could happen due to unforeseen factors, which require further investigation. The MRTA had noticed prior water leakage and attempted fixes, leading to traffic closures and evacuations before the incident.
The exact size of the leak causing water intrusion cannot be determined until the water dries, which is not possible yet because pressure between inside and outside the tunnel must be maintained. The tunnel withstands pressure from all sides, so the method involves maintaining balanced pressure inside and outside and sealing outer voids. The sealing is expected to take about 7-12 days using engineering techniques to equalize pressure at tunnel ends.
For compensation, the contractor has insurance to cover affected parties. Residents displaced must be cared for by the contractor, and Siriphong assured that proper assistance is in place.
Siriphong said the urgent directive from the Prime Minister is to prioritize safety. The process follows engineering principles to avoid disputes over procedural choices. The Ministry of Transport is working to resolve the problem swiftly for the public.
"I sincerely apologize for what has happened. Nevertheless, the Ministry of Transport will supervise and resolve the problem at every step, following the Prime Minister’s policy to prioritize public safety. Please be patient; we will strive to fix the issue fully soon," Siriphong said.
When asked about forming an investigation committee, Siriphong said experts from Thailand and abroad, including the Department of Disaster Prevention and Mitigation and the Department of Public Works, were invited this morning. They debated professionally to reach conclusions, noting that relying on a single opinion for the entire case is insufficient.