Line 6 (Mumbai Metro)

Line 6 (Pink Line) of the Mumbai Metro is a rapid transit metro line in the city of Mumbai, Maharashtra, India. The 14.477 km elevated line will connect Lokhandwala Complex with Vikhroli and will have 13 stations.

Line 6 will also provide interchanges with Yellow Line 2 at Adarsh Nagar, with Aqua Line 3 at SEEPZ, with Green Line 4 at Kanjurmarg West, and with Red Line 7 at Jogeshwari Vikhroli Link Road. It also offers connectivity with the Mumbai Suburban Railway's Western line at Jogeshwari and with the Central line at Kanjurmarg.

Line 6 is expected to open by 2025.

Planning
A 19.5 km metro line connecting Bandra Kurla Complex with Kanjurmarg via the airport was proposed as Line 6 in the original Mumbai Metro master plan unveiled by the Mumbai Metropolitan Region Development Authority (MMRDA) in 2004. In June 2015, the MMRDA proposed building a 12 km metro line from JVLR to Kanjurmarg as part of a plan to build 6 new metro lines at a total estimated cost of inr 640000000000. On 19 October 2016, the Mumbai Metropolitan Region Development Authority (MMRDA), headed by Chief Minister Devendra Fadnavis, approved a plan to build a 14.47 km metro rail line connecting Lokhandwala Complex in Andheri to Vikhroli and Kanjurmarg in the east. The line would have 13 stations and was estimated to cost inr 66720000000. The detailed project report for Line 6 was prepared by the Delhi Metro Rail Corporation (DMRC) in December 2016. The project was approved by the Maharashtra Cabinet on 24 October 2017.

The MMRDA issued a tender to conduct a detailed aerial mapping survey of the alignment in April 2017. Authorities were to determine the location of trees along the alignment with an accuracy of up to 10 cm, utilizing a differential GPS (DGPS), while a digital aerial triangulation system is to help determine the types of trees, their heights and diameters. The project received Coastal Regulation Zone (CRZ) clearance from the Maharashtra Coastal Zone Management Authority (MCZMA) in June 2017. A 1.1 km stretch of Line 6 passes through CRZ areas at the junction of the JVLR and the Eastern Express Highway near Nehru Nagar. The MMRDA utilized a drone to carry out survey work for Line 6. The drones were fitted with 360 degrees camera that provide up to 3 millimetres (0.12 in) accuracy. The aerial survey takes less time than a regular survey, achieves greater accuracy and helps protect against false claims for compensation.

In November 2017, the MMRDA stated that it had reached an agreement with the Brihanmumbai Municipal Corporation (BMC) to build a 2 km section of Line 6 on a common pier with a flyover. The BMC had been planning to build a flyover connecting Jogeshwari West and the Jogeshwari Vikhroli Link Road (JVLR) along the same alignment of Line 6. Per the agreement, the metro piers and viaduct would be constructed first and the flyover would be built below it. Line 6 forms the top deck of a three deck structure on this 2 km stretch as the flyover itself passes over an existing rail overbridge.

In April 2018, the BMC stated that it was putting work on a proposed crocodile park at Powai Lake on hold until Line 6 was completed. The MMRDA faced criticism from Lokhandwala and Powai residents at a public consultation meeting held on 21 May 2019.

Alignment
The fully elevated line is 14.477 km long with 13 stations. The line begins at Swami Samarth Nagar station in Lokhandwala Complex and passes over Line 2A's viaduct near Infinity Mall junction on Link Road at a height of 20 metres. Line 6 continues east passing over railway lines at Jogeshwari, Line 7's viaduct at the Western Express Highway, and the JVLR. It continues along the periphery of Powai Lake and terminates at Vikhroli station on the Eastern Express Highway. Line 6 has a total of 50 curves along the route, including many sharp turns. The detailed project report noted that the ground along the alignment was "undulated" resulting in a gradient that was very steep.

Line 6 is the highest metro line in India. The average height of the pillars supporting the line is 16 metres (fourth highest in India), but passes at heights over 30 metres in some sections. The tallest pillar on Line 6 is located at Gandhi Nagar in Kanjurmarg. It is 38 metres in height and is the tallest metro pillar in India. The tallest station on the line is Kanjurmarg at height of 30 metres above ground level.

Construction
The DMRC was appointed as the implementing agency for the project by the MMRDA in November 2017. The DMRC invited bids for the construction of Line 6 on 28 November 2017. The work was split into 3 packages. The first package included the IIT Powai, Kanjurmarg West and Vikhroli (EEH) stations. The second package included the section from Lokhandwala to Mahakali Caves. Construction of the first two packages required the cutting 899 trees. The DMRC awarded J Kumar Infraprojects an inr 8670000000 contract for the second package from Lokhandwala to Mahakali Caves in August 2018.

Girder launching began in November 2020. The MMRDA stated in the same month that around 21% of the total work had been completed. A 29.5-metre tall straddle carrier was used to launch girders for the line. A crane at a construction site along the JVLR near Kanjurmarg toppled and collapsed while installing a concrete girder on 16 January 2022, resulting in the death of the crane operator. About half the work on the line had been completed by July 2022, and 65% of civil works had been completed by December 2022. On 6 July 2023, the MMRDA stated that it had completed building 657 out of 768 pillars (70.75%) required for Line 6.

Stations
The line will consist of 13 stations from Swami Samarth Nagar in Lokhandwala Complex in Andheri (West) to Vikhroli (East). It will have interchanges with Lines 2, 3, 4 and 7. Stations on the line will be equipped with platform screen doors.

Rolling stock
The MMRDA floated tenders to procure 108 metro cars for Line 6 in June 2023.

Depot
The depot for Line 6 is proposed to be located at Kanjurmarg.