The Blue Line is part of the Namma Metro rail network for the city of Bangalore, Karnataka, India. It consists of two sections - Phase-2A (Central Silk Board to Krishnarajapura) and Phase-2B (Krishnarajapura to Airport). Construction of Phase-2A began in August 2021. Construction of Phase-2B began in February 2022. The 58.19 km line connects Central Silk Board with the Kempegowda International Airport.
The line passes through the eastern part of Outer Ring Road and passes through many major tech hubs and neighbourhoods of the city, such as HSR Layout, Agara, Bellandur, Kadubeesanahalli, Marathahalli, Doddanekundi, Mahadevapura, Krishnarajapura, Kasturi Nagar, Horamavu, Kalyan Nagar, Hennur, Nagawara, Hebbal and then runs parallelly along the National Highway 44, where it passes through Kodigehalli, Jakkur, Yelahanka, Doddajala and then passes along the Airport Road.
The Line is mostly elevated but also has 2 at-grade (surface) sections, at the AFS Yelahanka Campus Bengaluru, and the Airport City station, and also has 1 underground section - at the KIA Terminals . There are 29 stations on the line of which 27 are elevated, 1 is at grade, and 1 is underground - making it the second line, after Purple Line, in the Namma Metro system to contain all 3 station types. The Blue Line will have interchanges with the Yellow Line at Central Silk Board, Purple Line at Krishnarajapura, Pink Line at Nagawara and a planned interchange with the proposed Orange Line at Hebbal.
Between Benniganahalli and Kasturi Nagar, a 500-metre section of the Bengaluru Suburban Rail Project's Mallige Line was redesigned to share infrastructure with Blue Line. Under this arrangement, the Kanaka line viaduct of the suburban rail network will run directly below the Blue Line viaduct for approximately 500 metres adjacent to the Benniganahalli flyover.
In June 2022, the BMRCL launched the first ever U Girder span on ORR-Airport metro line. The extension of the Purple Line and construction of the Yellow Line is completed and operational, where Construction of Pink Line is currently under progress. The Pink, Yellow and Blue lines will be CBTC-signaling enabled, unlike Namma Metro's first two lines (Purple and Green lines use distance-signaling). In June 2023, the Deputy Chief Minister of Karnataka D. K. Shivakumar informed that Metro line to Kempegowda International Airport will be completed by December 2026, plus or minus 3 months.
History HistoryPhaseSectionPlanned OpeningTerminalsLengthStations2AP2A ORRJune 2027Central Silk BoardKadubeesanahalli7March 2027KadubeesanahalliKrishnarajapura62BP2B APLMarch 2028KrishnarajapuraHebbal8September 2027HebbalKIAL Terminals8TotalCentral Silk BoardKIAL Terminals29
The routes under Phase-2A and Phase-2B (Blue Line) were at first considered a part of the Phase-3 of metro development, but were prioritized under Phase-2, as the Central Government requested BMRCL to begin work on the airport link as early as February 2012.
The route from Central Silkboard to K R Pura along the eastern part of Outer Ring Road (ORR) was included as Phase-2A since development on that part of ORR had leap-frogged much ahead of the rest of the city with huge number of new office buildings. As a result, traffic increased several fold with employees traveling from different parts of the city to this new CBD. Chief Minister of Karnataka, Siddaramaiah announced in September 2016 that a new line connecting Central Silk Board with KR Pura along ORR would be included in Phase 2 as Phase-2A of the project at an estimated cost of ₹4202 crores.
Kempegowda International Airport (opened during May 2008) being very far from city center (about 35 km), commuting time by road in traffic congestion is time-consuming. Hence, attention for building a fast mass transit was in the minds of planners from the very beginning, especially since air traffic had kept increasing. The old airport in Bengaluru, the HAL Airport, located well within the city, had closed for commercial operations as part of the terms of the PPP for the new airport.
To connect airport to city, there had initially been a proposal to build a 33 km (21 mi) high speed rail line from MG Road to Kempegowda International Airport (KIA). Cost was estimated at ₹5,767 crore (US$810 million). This was to be executed by an independent SPV - Bangalore Airport Rail Link Limited (BARLL). However, the plan for an exclusive city-airport high speed rail was canceled during October 2013 due to high cost and viability concerns.
It was decided that BMRCL would manage the airport rail project and a regular metro line with fewer halts would be built instead of a high speed rail. Following this, suggestions were invited from public during September 2016 to choose any one of nine possible extension routes from existing and proposed metro lines to the airport. The proposed extension routes had an average length of 30 km (19 mi), and cost estimates ranged between ₹4,500 crore and ₹7,000 crore. A 25.9 km (16.1 mi) extension from Nagawara via Kannur and Bagaluru was the shortest, while the 35.4 km (22.0 mi) extension from Yeshwanthpur via Yelahanka, Kannur and Bagaluru was the longest of the proposed routes. BMRC received 1,300 responses from the public. The shortest (25.9 km, 16.1 mi) extension of the Kalena Agrahara (previously Gottigere) – Nagawara line via Kannur and Bagaluru to the airport emerged as the most popular choice. In February 2017, the Centre requested BMRC to start work on the airport link before Phase 3. Thus, the Airport Line was included in Phase 2 as Phase 2B.
Since the airport's managing company, Bengaluru International Airport Limited (BIAL) forbade underground construction from the southern side of the airport due to security concerns as it would have to pass beneath the airport's second runway, the shortest route options (i.e. extending the Pink line from Nagawara directly north) were eliminated. An alternate route proceeding north till RK Hegde Nagar and then turning west to Jakkur and then along Airport Road was explored. Bangalore Development Minister K. J. George announced on 12 May 2017 that the government had finalized the Nagawara—Ramakrishna Hegde Nagar—Jakkur—Yelahanka route to the airport. However, this route had an obstacle as a high-pressure petroleum pipeline was passing through the originally proposed route.
This was changed and on 10 January 2019, the State Cabinet approved a change in alignment for the proposed metro line to the airport. The new line would begin at Krishnarajapura (K.R. Pura) and be aligned along the northern part of ORR (Outer Ring road), passing Kasturinagar, Nagawara, Hebbal, and Jakkur before heading towards the airport. The line would be long, about longer than the route previously proposed, estimated to cost ₹10,584 crore (US$1.5 billion).
Tendering Blue Line Pre-Construction ActivityTenderingSectionActivitySuccessful Bid /CostContractorAwardPhase-2A/ORR/2018/Demolition/DLN-9/35Central Silk Board to K. R. PuraDemolitionB R Chawla Demolition12 Oct 2018Phase-2A & 2B/Via & Stns /PMC/2020/72Central Silk Board to KIALProject Management ConsultantRITES17 Dec 2021Phase-2A&2B/DDC/Sec-1Central Silk Board - HBR LayoutDetailed Design ConsultantSMEC International07 Feb 2020Phase-2A&2B/DDC/Sec-2HBR Layout - KIAL AirportDetailed Design ConsultantAECOM – CEG JV12 Feb 2020Airport Depot & Byp Depot/DDC/2021/76Baiyappanahalli & Airport DepotDetailed Design ConsultantAECOM – CEG JV16 Sept 2021CE-US/ELE/EHV/ORR/PH-2ACentral Silk Board to K.R. PuraConversion of Electrical LinesRahul Cables13 May 2022 MiscellaneousKR Pura - KIAL AirportVarious19 Dec 2020Total Civil WorkTenderingSectionLengthSuccessful Bid /CostContractorAwardPackage 2A/P1/60(a)Central Silk Board - KodibeesanahalliAfcons25 May 2021Package 2A/P2/60(b)Kodibeesanahalli - KR PuraShankaranarayana25 May 2021Package 2B/P2/69(a)KR Pura - KempapuraNCC17 Nov 2021Package 2B/P2/69(b)Kempapura - Bagalur CrossNCC17 Nov 2021Package 2B/P2/69(c)Bagalur Cross - KIAL TerminalsNCC17 Nov 2021 Veerannapalya StationVeerannapalya Station was initially awarded to NCC as part of Package 2B/P2/69(a). However, due to a severe delay in shifting an underground gas pipeline the station was unloaded from NCC scope of work. BMRCL re-invited tenders for this station, which was later awarded to URC Constructions.URC Constructions07 Feb 2025Total Depot WorkTenderingSuccessful Bid /CostContractorAwardRemodelling Baiyappanahalli DepotJ Kumar – AICPL JV18 Mar 2023Airport DepotJ Kumar – AICPL JV18 Mar 2023Total Architectural Finishing WorksTenderingSuccessful Bid /CostContractorAwardPackage 2A-A1Central Silk Board - KadubeesanahalliMR Constructions16 Dec 2024Package 2A-A2Kodibeesanahalli - KR PuraGodrej & Boyce 09 Nov 2024Phase-2B/Arch. Works/A2/RT/2025/136Hebbal - DoddajalaNSL Construction19 Jan 2026Phase-2B/Arch. Works/A1/2025/129Kasturi Nagar - KempapuraBridge and Roof04 Feb 2026Total MiscellaneousTenderingSuccessful Bid /CostContractorAwardLand AcquisitionN/A2020Phase-2A and 2B/Plantations/2023/95Plantation and Maintenance of TreesVarious28 Mar 2023Phase-2A and 2B/Track Work/2022/93Ballastless Track WorkLarsen & Toubro02 Jun 20235RS-DMRolling Stock (222 Coaches)BEML08 Aug 2023Phase-2A & 2B/Turnouts /2023/101Track TurnoutVossloh22 Mar 2024EPC6-CCEngineering, Supply, Erection, Testing and Commissioning of Power SupplyKEC International10 Jun 2024EPC5-CC750V DC Third Rail electrificationSiemens – RVNL JV11 Jun 2024Signalling System (CBTC) & PSDAlstom12 Jun 2024Phase II/ 9 ESCAL - DM Elevators & EscalatorsJohnson Lifts6 Feb 2025E&M-6Electrical & Mechanical Jakson7 Feb 2025Phase II/6 ELEV-DMMachine Room Less Gearless Elevators20 Mar 2025BMRCL/Travellator (R5 CSB to Ph2A/P1 CSB)/ Works /2026/146Travellator and Connecting Walkway between Yellow Line and Blue line ORR Central Silk Board Metro Stations (to be completed in 9 months after successful bidding)Milan Road BuildtechPhase-2B/Arch. Works/A1/2025/129Automatic Fare Collection SystemTenders Under EvaluationTotalTotal Line Cost
Phase-2A BMRCL prepared the detailed project report for the proposed Central Silk Board - KR Pura Line and submitted the DPR to the state government on 28 October 2016. Phase 2A was approved by the State Cabinet on 1 March 2017.
Tenders for the ORR (East) Metro line were called in February 2018 and IL&FS emerged the lowest bidder for all packages. However, the tenders were quashed due to cash flow problems and bankruptcy proceedings by the selected firm, IL&FS. A second round of tendering was done in December 2019. The project cost was revised to ₹5994 crores. Fresh bids were received by multiple firms in March 2020. There are two packages. The first package included 2.84 km of ramps for a flyover at Central Silk board junction in addition to 9.859 km of viaduct with six elevated stations. The second package was for 8.377 km viaduct with seven elevated stations, 1.097 km depot line and a 0.30 km pocket track.
Central government's approval was much delayed and finally received in April-2021. Tenders were awarded in May-2021 and construction on Phase-2A finally began in August-2021. Opening of this phase is by March 2027.
Phase-2B
DPR for the Airport Line had been prepared in September 2017 and cleared by Government of Karnataka in January 2019.
Tenders for the Airport line were called in July 2020. There are three packages. The first package was for 11.003 km viaduct, including 281 mtrs viaduct beyond Phase-2A with eight elevated stations and 650 mtrs link line to Baiyyappanahalli depot. The second package was for 11.678 km viaduct with 250 mtrs pocket track and two elevated stations. The third package was for 15.011 km viaduct, including 718.18 mtrs cut and cover portion in front of Yelahanka Air Force Station. All three packages include road widening, utility diversion and allied works.