Published on: December 8, 2025

INDIAN RAILWAYS IS EXPANDING ITS HIGH DENSITY NETWORK (HDN)

INDIAN RAILWAYS IS EXPANDING ITS HIGH DENSITY NETWORK (HDN)

NEWS – The Union Cabinet has approved the construction of third and fourth lines on the Badlapur–Karjat section (32 km) in Maharashtra—an important addition to the Mumbai Suburban Corridor and part of the wider Mumbai–Chennai High Density Network.

HIGHLIGHTS

What Are High Density Corridors?

  • HDNs are passenger–freight mixed corridors experiencing extremely high congestion.
  • They form 16% of total route length but carry 41% of total rail traffic.
  • Capacity utilisation on most HDN sections exceeds 100–150%, much beyond the optimal 70–80%.

Golden Quadrilateral

  • The Golden Quadrilateral comprises rail links connecting Delhi, Mumbai, Chennai and Kolkata.
  • Many HDN sections, including Delhi–Mumbai (HDN-3), are part of this quadrilateral.

Why Railways Matter to the Indian Economy

  • Moves 1.2 billion tonnes of freight annually, critical for bulk commodities like coal, foodgrains & cement.
  • Cost-effective long-distance transport, reducing logistics cost.
  • Supports national integration, mobility and economic competitiveness.

Significance of Expanding HDN

  1. Severe Congestion
  • HDN has 237 sections; only 10% operate below 80% capacity.
  • 33 sections are running at more than 150% capacity, causing delays, operational inefficiencies and safety risks.
  1. Future Congestion Forecasts
  • National Rail Plan (NRP) warns that by 2051,
    • 92% of HDN will operate above 150% capacity without intervention.
  • By 2031,
    • 50% of HDN will exceed 150% utilisation,
    • only 9% will operate within the optimal 70–100% bandwidth.

Importance of Dedicated Freight Corridors (DFCs)

  • Reduce freight load on HDNs.
  • Increase average freight speeds to 50–60 km/h (vs. 25 km/h on saturated routes).
  • Free up mainlines for more passenger trains.

Government Initiatives

  • Doubling, tripling, and quadrupling of lines on congested sections.
  • Construction of Eastern & Western DFCs; planning more DFCs under NRP.
  • Automatic signalling, electrification, and modern train control systems.