The Mumbai Metropolitan Regional Development Authority (MMRDA) has made significant progress in establishing a comprehensive metro network across the Mumbai Metropolitan Region (MMR), with almost three-fourths of the planned pillars for six metro lines now erected. Of the 4,929 pillars that will connect Mumbaikars to various corners of the MMR, 3,603 have already been constructed, representing a completion rate of 73.09%.

The six metro lines currently under construction are Metro 2B (D N Nagar to Mandale, Mankhurd), Metro 4 (Wadala to Kasarvadavali), Metro 4A (Kasarvadavali to Gaimukh), Metro Line 5 Phase I (Thane to Bhiwandi), Metro Line 6 (Swami Samartha Nagar to Vikhroli), and Metro Line 9 (Dahisar to Mira-Bhayandar).

During the construction process, significant emphasis is placed on the casting and erection of heavy-weight precast elements, such as pier caps, U-girders, and I-girders. These precast elements are cast at different yards, transported to the site, and erected using cranes with capacities ranging from 350 metric tonnes to 500 metric tonnes. To minimise disruptions to public traffic and ensure safety, the transportation and erection activities of these precast elements are carried out at night.