DTL3 – C935 will consist of two 770m long segmentally lined tunnels. This technically challenging tunnelling project, through varied ground conditions ranging from marine clays through to boulder clays, is on the deepest section DTL3 and also passes beneath DTL2 tunnels. The project also includes the construction of one cross passage located 40m below ground level between the bored tunnels, and one underground station (DT22 Station) which is approximately 150m long, 23m wide, and 30m deep.

DTL3 will be an underground Mass Rapid Transit (MRT) System extending from Downtown Line Stage One (DTL1) Chinatown Station and terminating at the Expo station near Changi Business Park. It is a 21km automatic, driverless metro in Singapore. Construction of DTL3 started in November 2011 with the line opening scheduled for 2017.