SRINAGAR: Zoji La tunnel, an upcoming strategic corridor that will provide all-weather connectivity between Kashmir and Ladakh, is nearing a defining moment, with engineers inching towards a “breakthrough” final blast expected around May 30.Work is progressing at about four meters per day from both ends — Sonamarg (Baltal) in Kashmir and Minamarg in Ladakh — using controlled drilling and blasting. Only 300 meters of the 13.155km tunnel is left to excavate, Harpal Singh, chief operating officer (COO) of Megha Engineering and Infrastructure Ltd (MEIL), told TOI. The Hyderabad-based company is executing the project.“The final blast will bring the excavation phase to a close, completing the tunnel’s core structure,” Singh said, adding the blast will signal the physical connection between Kashmir and Ladakh.According to Singh, this historic milestone will be achieved by reducing tunnel excavation to zero within 30 to 35 days. “Breakthrough will ensure speedy construction of the remaining works, including concrete lining, permanent tunnel drainage, installation of surveillance equipment, control buildings, underground transformers and (traffic) smoke control systems,” Singh explained.The tunnel is still another two-and-a-half years from completion. Before it is opened to the public, the breakthrough will allow construction teams and machines to move seamlessly between two ends, streamlining work. “The teams and equipment can move through the tunnel without any hassle,” Singh said, adding this will help sustain construction through winters when heavy snowfall in Sonamarg halts surface movement.The tunnel will reduce distance between the two ends (Sonamarg and Minamarg) from 49km to 43km and increase vehicle speeds from 30kmph to 70kmph, officials said.