Title - Kottavasal tunnel caves in

The sluggish progress of the gauge conversion (GC) work on the Punalur-Shengottai rail section may get further delayed following the caving-in of a portion of the 906-metres-long Aryankavu-Puliyara (Kottavasal) tunnel at 2 a.m. on Wednesday.

The portion that caved in was 25 metre from the Puliyara end, coming under the Madurai Railway Division. While the Aryankavu end is in Kerala, the Puliyara end is in Tirunelveli district of Tamil Nadu.

Railway sources said the development could further delay the completion of the fund-starved GC work. The tunnel, constructed in 1902 for metre gauge trains, was being widened to accommodate broad-gauge traffic. It was the roof portion that caved in, creating an open cavity above. The portion that came down was on the 500-metre course of the tunnel where widening work neared completion. Railway authorities said such caving-in was “usual during construction of tunnels through a geographical profile that is very fragile and prone to rock sliding”. They said the work had been awarded to a contractor who had a reputation in constructing tunnels in even more fragile locations of the Himalayan region.

Terming it as “roof funnelling” in civil construction terminology, the authorities said work for plugging the portion that caved-in would be taken up on a war footing immediately.