A week has passed since the reinforced soil wall at Mylakkadu in Kollam, Kerala, collapsed amid the National Highway development. The National Highways Authority of India (NHAI) was swift to take action after the event saw cracks develop in the service road, trapping cars and even a school bus on December 5, 2025.
Now termed the "Mylakkadu failure", the NHAI confirmed that the fault occurred due to the soil at the foundation being too weak to support the fill. This "Deep-Seated Shear/Bearing Capacity Failure" involved a 9.4m high reinforced soil wall approach to a vehicular underpass.
"NHAI has acted swiftly and severely to ensure accountability. The Concessionaire and its Promoters (M/s Shivalaya) and the Independent Engineer (M/s Feedback - Satra JV) have been temporarily suspended from bidding for future projects. They have also been issued Show Cause Notices for potential debarment (up to 3 years for Concessionaire and up to 2 years for IE) along with monetary penalties. The Project Manager of the Concessionaire and the Resident Engineer of IE have been immediately removed from the project site," the Highways ministry recently updated.
In line with this, the NHAI also launched an overall investigation into the ongoing work along the NH-66, including intensive soil testing across the length of the new highway.
"I was on my bike (motorcycle) coming to Ayathil when I saw it," said Sibi, an auto-detailing shop manager in Kollam. "There were people helping children out of a school bus that was stuck. There was also a new car with a temporary registration plate that got stuck."
Locals in the area were visibly blaming the oversight of the NH-66 work, another person in the area said.
A high-level expert committee, including Dr Jimmy Thomas of IIT-Kanpur and Dr T.K. Sudheesh of IIT-Palakkad, visited the site last Saturday, the ministry stated, to "investigate the causes of failure and suggest remedial actions."
This came after the findings of another expert committee were put into action after the May 2025 NH-66 collapse at Kuriyad, Malappuram, in Kerala. The concessionaire proposed a new Rs 80 crore flyover as remedial action at their own cost, with the reconstruction scheduled for completion by February 2026.
"The rectification in the entire stretch of NH-66 in Kerala is scheduled for completion by May 2026," Union Minister Nitin Gadkari announced at the Rajya Sabha back in July 2025.
Now, the Mylakkadu incident has added to further woes. "NHAI has appointed 18 Geotechnical Agencies to conduct rigorous soil sampling and testing at 378 structure/ RS Walls locations across 18 projects on NH-66 in Kerala. This includes sites that are already constructed, in progress, and yet to start. Agencies will deploy multiple rigs within 7–10 days to start the work, aiming to complete tests at 100 locations within one month and the remaining within three months," the Highways ministry said on Wednesday.
Moreover, the design and construction of every reinforced soil wall will be re-checked across the NH-66 based on the comprehensive field and lab reports. "RS Walls will only be accepted after this process is complete and quality is confirmed. Accountability will be fixed for all lapses found during this review," the ministry added.
The NHAI also expanded its safety audits, with it already engaging RITES to conduct a thorough audit following "a separate incident" involving the falling of girders on the Aroor-Thuravoor Elevated Road Project in November.
"These safety audits will now be expanded to cover other projects on NH-66 to proactively identify and rectify any potential safety concerns," added the ministry.
