CHENNAI: The Southern Railway has started building dedicated pit lines at the Basin Bridge coaching depot for the maintenance of Vande Bharat (VB) trains. The six-rake facility is being developed at a cost of Rs 19 crore.Highly-placed sources from the Railways said 75 VB trains are to be introduced across India by August 15 next year. “Before that, a Chennai-Bengaluru Vande Bharat Express is likely to be launched. A feasibility study has been conducted,” said an official.