NHAI Acts on NH-66 RS Wall Failures

The National Highways Authority of India (NHAI) has taken immediate and stringent action following the failure of a Reinforced Soil (RS) wall at Mylakkadu in Kollam District, Kerala, on NH-66, which collapsed on December 5, 2025, during construction.

Through its Press Release dated December 10, 2025, NHAI has addressed not only the immediate structural failure but also broader issues relating to accountability, geotechnical diligence, and safety governance in highway development.

The failure involved a 9.4-metre-high RS wall forming the approach to a vehicular underpass under the Kollam–Kadambattukonam Project. Preliminary assessments indicate a deep-seated shear or bearing capacity failure, attributed to weak foundation soil incapable of supporting the fill.

In response, NHAI has initiated firm accountability measures against the Concessionaire (M/s Shivalaya), its promoters, and the Independent Engineer, including:

• temporary suspension from bidding for future projects;
• issuance of Show Cause Notices proposing debarment (up to three years for the Concessionaire and two years for the Independent Engineer);
• imposition of monetary penalties; and
• immediate removal of the Project Manager and Resident Engineer from the project site.

While RS wall technology is generally regarded as structurally sound, NHAI has flagged serious concerns regarding soil quality and bearing capacity in the design and construction of RS walls along NH-66 in Kerala. To address these systemic issues, NHAI has launched a multi-pronged corrective initiative, which includes:

• constitution of a high-level expert committee comprising specialists from IIT Kanpur and IIT Palakkad, which visited the site on 6 December 2025 to identify the causes of failure and recommend remedial measures. The findings of an earlier committee constituted after the Kooriyad incident are also being implemented;
• engagement of 18 geotechnical agencies to carry out soil sampling and testing at 378 RS wall and structural locations across 18 NH-66 projects in Kerala, covering completed, ongoing, and proposed works;
• comprehensive re-validation of the design and construction of all RS walls, with dismantling and reconstruction wherever required. Acceptance of the structures will be subject to quality confirmation, and accountability will be fixed for any identified lapses; and
• expansion of safety audits across NH-66 projects. Following a separate girder-fall incident on the Aroor–Thuravoor Elevated Road Project, NHAI has engaged RITES for safety audits, which will now be extended to other projects along the corridor.

These measures underscore NHAI’s zero-tolerance approach to safety lapses and reaffirm its commitment to quality control, geotechnical due diligence, and contractor accountability in large-scale highway infrastructure projects. Overall, the actions signal a tightening of regulatory and contractual oversight in highway construction, with enhanced scrutiny of soil investigations, design validation, and supervision standards to protect public safety and ensure the long-term structural integrity of the NH-66 corridor.