Contract 919 for the design and construction of Stevens station and associated tunnels was awarded to Sembawang Engineers and Constructors Pte Ltd at an approximate value of in July 2009. The contract also includes the construction of the adjacent Stevens station. Construction of the station was scheduled to commence in the third quarter of 2009 and targeted to complete by 2015. On 11 March 2012, a worker was killed at a site near the Botanic Gardens, beside the contractor's site office after a concrete slab fell on him. 35-year-old Masud al-Mamun was operating an excavator deep in the ground when the slab fell on him. Rescuers had to use a breaking tool kit to break a portion of the concrete slab. It took nearly five hours to reach the man lying motionless on the ground. This is the first casualty related case in the construction of the Downtown line.