Hyderabad, Aug. 31 -- The Srisailam Left Bank Canal (SLBC) tunnel project in Telangana's Nagarkurnool district has achieved a crucial breakthrough, with engineers successfully negotiating one of the most dangerous geological formations in the Nallamala forests along the revised alignment, officials familiar with the matter said.

The breakthrough comes more than a year after the deadly tunnel collapse on February 22, 2025, which claimed the lives of eight workers and forced authorities to abandon the original alignment in the affected stretch.

The latest achievement is significant as the shear zone encountered on the new alignment posed a major challenge to excavation because of unstable rock conditions and high geological risks.

A shea...