Centre asks for tweaking Metro Phase 3A's 'high' cost

Bengaluru: Namma Metro is set to appoint an independent consultant to reassess and reduce the high estimated cost of the Sarjapur-Hebbal line, following concerns raised by the Centre. 

The 36.59-km Phase 3A, also called the Red Line, will connect Sarjapur in southeastern Bengaluru to Hebbal in the north. It is estimated to cost Rs 28,405 crore, or Rs 776.3 crore per km, the most expensive in Namma Metro's history. 

After being approved by the Karnataka cabinet in December 2024, Phase 3A is currently being vetted by the Ministry of Housing and Urban Affairs. 

A senior official in the Bangalore Metro Rail Corporation Limited (BMRCL) stated that the ministry found the estimated cost "higher" than benchmark norms. 

"Our cost estimate for Phase 3A's underground section was based on the Pink Line, which is currently under construction. However, the ministry has asked us to appoint an independent consultant to reassess and reduce the cost," the official told DH on the condition of anonymity. 

The independent consultant's report, expected in three months, will be sent to the ministry, which will then decide whether to approve Phase 3A or suggest more changes, the official added. 

The process may delay the Centre's approval, which is expected by December 2025. The project's tentative deadline is 2031. 

Cost benchmarking for metro projects is based on 13 factors, including alignment and formation, station buildings, traction and power supply, signalling and telecommunication, depots and trainsets. 

For underground lines, the length of station boxes has to be excluded while calculating the length of the tunnelling section. 

Underground metro stations require about 10 times more energy than elevated ones. While underground station boxes are typically 240–265 metres long for a six-coach platform, reducing these lengths to 190–200 metres or less can cut civil costs. 

Phase 3A will consist of a 14.44-km underground section from Koramangala 2nd Block through the Central Business District (CBD). 

No change in alignment

An X post by Deputy Chief Minister DK Shivakumar that Phase 3A will run from Sarjapur to Iblur (14 km) and from Agara to Koramangala 3rd Block (2.45 km) set off speculations that the government had changed the metro line's alignment for the proposed tunnel road, which will also link Sarjapur to Hebbal. 

However, two senior BMRCL officials denied this. "There is no change in alignment," one of them said. 

The second official clarified that Shivakumar likely mentioned only those stretches of Phase 3A where double-deck flyovers are planned. 

He said that double-deck flyovers would be built on two stretches: Sarjapur to Iblur (14 km) and Agara to Koramangala 3rd Block (2.45 km). 

"The double-deck flyover will be limited to the overground section. If there's any inaccuracy, we'll bring it to his notice and get it corrected," the official added.