New Guidelines for High-Speed Access-Controlled National Highways

The National Highways Authority of India (NHAI) has issued comprehensive guidelines for the planning and design of High-Speed Access-Controlled National Highways, other than Expressways. The guidelines will apply to upcoming four-lane and six-lane Greenfield and Brownfield High-Speed Access-Controlled National Highways and seek to establish greater consistency in planning, safety and technical standards.

The guidelines place emphasis on data-driven planning and require comprehensive assessment of existing and future traffic. Traffic projections are to account for existing and diverted traffic, anticipated growth in freight movement and data from toll transactions and other reliable sources to improve the accuracy of traffic estimates.

Lane configuration and highway width are to be determined based on detailed traffic assessment. Corridors with traffic flow of up to 15,000 vehicles are to have four-lane highways with four-lane structures and a width of 60 metres, while corridors with traffic flow between 15,000 and 25,000 vehicles are to have four-lane highways with six-lane structures and a width of 70 metres. Corridors with traffic flow between 25,000 and 40,000 vehicles are to have six-lane highways with six-lane structures and a width of 70 metres.

The guidelines provide for greater integration of technology in highway construction, including the use of Automated and Intelligent Machine-aided Construction (AI-MC) technology for embankments and highway pavements in accordance with applicable Ministry of Road Transport and Highways (MoRTH) guidelines. Provisions have also been made for the adoption of Multi Lane Free Flow (MLFF) tolling on High-Speed Corridors.

To strengthen access control and facilitate uninterrupted traffic movement, interchanges with ramps are to be provided at crossings with Expressways, National Highways, State Highways and important arterial roads generating substantial traffic, as well as roads providing connectivity to major traffic-generating destinations such as ports, airports, Multi-Modal Logistics Parks, industrial areas and major tourist destinations.

The guidelines further prescribe comprehensive drainage planning as part of the Detailed Project Report (DPR) process. The planning is required to identify appropriate rainwater disposal arrangements and provide for the management of water around underpasses, flyovers, depressed medians and other structures to mitigate waterlogging and potential damage to highway infrastructure.

Environmental measures have also been incorporated into the planning framework, including landscaping and plantation at suitable locations such as loop areas, below flyovers and medians, with drip irrigation systems to be provided on National Highway medians, taking into account local climate, topography and environmental conditions.

According to NHAI, there were previously no separate standards for the planning and design of access-controlled High-Speed National Highways other than Expressways, and variations had been observed in the standards adopted for preparing DPRs for such corridors. The guidelines are aligned with the Government’s roadmap for developing 50,000 km of access-controlled High-Speed Corridors under Viksit Bharat 2047.