Railways plans 5th, 6th lines on high-density corridors to boost capacity
Indian Railways has drawn up plans to add 5th and 6th railway lines on its most congested High-Density Network (HDN) corridors, aimed at significantly boosting freight and passenger throughput.
The move is part of the National Rail Plan (NRP), which envisions increasing capacity ahead of demand to ensure that Indian Railways can meet projected traffic by 2050.
Recent project sanctions worth Rs 871 crore include doubling, tripling, and quadrupling of specific stretches across multiple railway zones, including work on the Energy, Mineral and Cement (EMC) corridor.
The Badlapur-Karjat stretch in Maharashtra (part of the Mumbai-Chennai HDN) has received approval for a 3rd and 4th line addition, extending the Mumbai suburban corridor.
Capacity augmentation on HDN corridors is also linked to the Dedicated Freight Corridor (DFC) strategy — once freight moves to DFCs, HDN tracks are expected to free up for passenger trains.
High-Density Network (HDN) — India's Most Congested Rail Corridors
The High-Density Network refers to the seven busiest rail corridors on Indian Railways, identified based on traffic throughput and capacity utilisation. These seven corridors together constitute only about 16% of the total route-km of Indian Railways (approximately 11,051 route-km out of 69,181 route-km) but carry 41% of all rail traffic. Most of these corridors operate well above their designed capacity — 95% of the HDN runs above the optimal threshold.
The 7 HDN Corridors: 1. Howrah–Delhi (via Asansol, Dhanbad, Prayagraj, Kanpur) — ~1,422 km 2. Howrah–Mumbai (via Kharagpur, Tatanagar, Nagpur, Bhusaval) — ~2,039 km 3. Mumbai–Delhi (Western and Central lines) 4. Delhi–Guwahati 5. Delhi–Chennai 6. Howrah–Chennai — ~1,117 km 7. Mumbai–Chennai — ~1,238 km
Key Details
- Capacity utilisation on many HDN sections exceeds 120-150%, causing delays and bottlenecks.
- The National Rail Plan (NRP) recommends converting most HDN corridors to triple or quadruple lines (HDN 1, 2, 3, 4, 6, and 7).
- Adding 5th and 6th lines is a step beyond the NRP's original quadrupling vision, targeting the most saturated stretches.
The proposal for 5th and 6th lines is a direct response to the persistent overcrowding on HDN corridors even after existing doubling/tripling projects — demonstrating that demand growth is outpacing incremental capacity expansion.
Dedicated Freight Corridors (DFC) — Structural Decongestion Strategy
The Dedicated Freight Corridor (DFC) project creates exclusive freight-only tracks parallel to existing HDN routes, allowing Indian Railways to bifurcate passenger and freight traffic. The two DFCs — Western (WDFC: Dadri to JNPT, ~1,506 km) and Eastern (EDFC: Ludhiana to Dankuni, ~1,875 km) — are the primary structural solution for HDN decongestion. The DFC Corporation of India Ltd (DFCCIL) is the implementing agency.
Key Details
- WDFC and EDFC run broadly parallel to the Howrah-Delhi and Mumbai-Delhi HDN corridors respectively.
- DFCs enable 25-tonne axle load freight trains (vs. 22.9 tonnes on standard tracks) at speeds of 100 kmph for freight.
- Eastern DFC operational sections: Khurja-Pilkhani, New Bhaupur-New Khurja (fully commissioned up to Ludhiana).
- Western DFC: New Rewari to Shabad (Palanpur) section commissioned.
- By shifting freight trains to DFCs, HDN tracks gain capacity for additional/faster passenger trains.
The 5th and 6th line proposal complements DFC capacity — even after freight decongestion via DFCs, the passenger traffic volume on HDN corridors requires additional tracks to meet future demand.
National Rail Plan (NRP) 2030 — Long-Term Infrastructure Vision
The National Rail Plan for India (NRP) was developed by Indian Railways and finalised in 2021, targeting a 45% modal share of freight traffic (from ~27% currently) and creating sufficient capacity to handle projected 2050 traffic volumes. It sets out specific interventions for HDN including track multiplication, electrification, automatic signalling, and speed upgrades.
Key Details
- NRP aims to create a future-ready rail system by 2024-2030 and project 2050 demand scenarios.
- Capital outlay for Indian Railways in Union Budget 2024-25: Rs 2,52,200 crore (highest ever).
- Indian Railways operates the world's 4th largest rail network by route-km.
- Freight revenue contributes approximately 70% of Indian Railways' total revenue, cross-subsidising passenger fares.
- Energy, Mineral and Cement (EMC) corridors are a subset of NRP designed specifically for bulk commodity movement (coal, iron ore, cement, steel).
The 5th and 6th line additions are within the NRP framework — specifically targeting corridors where projections show even quadrupling will be insufficient to meet 2030+ demand.
- HDN: 7 corridors, ~11,051 route-km (~16% of total network), carries 41% of rail traffic.
- 95% of HDN operates above optimal capacity thresholds.
- Recent project sanctions: Rs 871 crore (February 2026).
- Badlapur-Karjat 3rd and 4th line: part of 1,238-km Mumbai-Chennai HDN.
- Western DFC: ~1,506 km (Dadri to JNPT); Eastern DFC: ~1,875 km (Ludhiana to Dankuni).
- Indian Railways total route-km: ~69,181 km (4th largest globally).
- Union Budget 2024-25 capital outlay for Railways: Rs 2,52,200 crore.
- National Rail Plan finalized: 2021; target modal freight share: 45%.