Road Tunnel Collapse Prevention: MoRTH Guidelines

New Delhi, Dec 12 (PTI) To ensure safety and structural integrity of road tunnel projects, the Ministry of Road Transport and Highways (MoRTH) has said that at the time of the alignment survey, the geological maps and National Landslide Susceptibility Mapping published by the Geological Survey of India (GSI) must be consulted.

The ministry, in its guidelines for prevention and mitigation of road tunnel collapses, said all critical aspects of the contract milestones, scheduling, provisions for variations, risk-sharing mechanisms and force majeure must be addressed unambiguously.

"This ensures clarity and minimises the potential for disputes during project execution," it said.

The guidelines said the tunnel shape shall be evaluated not only in terms of space requirements but also for structural stability. It also emphasised that effective management of groundwater is essential for ensuring the long-term stability of the tunnel, and the design must include appropriate measures for waterproofing and drainage.

In regions with seismic activity, tunnel design must account for potential stresses and strains induced by earthquakes, according to the guidelines. It said the agency engaged in tunnel construction by virtue of its technical and professional knowledge and expertise shall play key supportive role during rescue operation led by the specialized agencies such as NDRF, SDRF, and DDMA.

In the recent past, there have been incidents of tunnel collapses during construction, stranding the workers -and in some cases-losing their lives. In such emergencies, rescue operations are carried out in coordination with agencies like the NDRF, SDRF, and the Armed Forces. On November 12, 2023, a total of 41 workers were trapped after a portion of the under-construction Silkyara tunnel in Uttarakhand collapsed. The workers were rescued on November 28.