Purple Line takes a step ahead as TBM Durga tunnels past RCTC
Times of India | 7 January 2026
Kolkata: Tunnelling for the city's Purple Line has crossed a milestone at the Royal Calcutta Turf Club (RCTC), part of the sprawling Kolkata Race Course founded in 1847.
The Race Course has been a part of the city's history for several decades. Queen Elizabeth II visited RCTC in Feb 1961. Old videos show people thronging the streets to catch a glimpse of the Queen and Prince Philip, her husband and the Duke of Edinburgh. On Feb 18, 1961, the Queen had presented her own trophy and watch the Queen Elizabeth II Cup tournament. The Queen's Cup, initially called Victoria Cup, has been played at RCTC since 1856. The Queen also visited Victoria Memorial Hall, where another Purple Line station is coming up.
"It was a tricky affair waiting and watching for first of the twin giant tunnel-boring machines (TBMs) pass below RCTC, which is our soul," said Danny David, who has been associated with the club for several decades. "RVNL engineers were in close touch with our engineers to allow the first TBM pass through the stands, founded in 1901 and 1902, respectively," he said.
The first tunnel borer, TBM Durga, which started digging the Esplanade-bound tunnel on July 10 last year, reached RCTC around Nov-end and crossed the heritage zone after covering around 600m. RVNL, which is implementing the 14km Joka-Esplanade project, also called the Purple Line, fitted the heritage stands with sensors for live monitoring to detect the slightest ground settlement. Durga is around 100m long, weighs about 600 tonnes, and has an outer diameter of 6.6m. She now has a straight, hassle-free path till Victoria Memorial station.
Once she reached the under-construction Purple Line's Victoria station, she will be extracted again to dig around 900m till Park Street.
RVNL earlier announced that the first phase of tunnelling from Kidderpore to Victoria will be over in Dec, 2026, with Durga reaching Victoria in June followed by sibling TBM Divya in Dec this year. TBM Divya, digging the second tunnel, reached Tolly's nullah and will be reaching RCTC some time next month. Tunnelling up to Park Street should end by March 2027.
The two TBMs, lowered into a launching shaft at St Thomas' Boys' School in Kidderpore, are part of the push to complete tunnelling 1.7km between Kidderpore and Park Street. The Purple Line now runs along an 8km elevated stretch between Joka and Majerhat. The launching shaft inside the school campus is 37m long, 22m wide and 17m deep.