NHAI sets uniform design norms for high-speed access-controlled highways

The National Highways Authority of India (NHAI) has introduced a uniform design framework for high-speed access-controlled national highways, seeking to standardize how such corridors are planned and designed as India expands its network of high-speed roads.

New Delhi: The National Highways Authority of India (NHAI) has introduced a uniform design framework for high-speed access-controlled national highways, seeking to standardize how such corridors are planned and designed as India expands its network of high-speed roads.

The guidelines, issued on Monday, apply to the upcoming four- and six-lane access-controlled greenfield and brownfield national highways, excluding expressways. They assume significance as the government targets the development of 50,000 km of access-controlled high-speed corridors under its Viksit Bharat 2047 road map.

Until now, there were no separate standards governing the planning and design of access-controlled high-speed national highways other than expressways, NHAI said. This has led to variations in the technical standards used to prepare detailed project reports (DPRs) across different corridors.

Consistency sought

The new framework seeks to bring consistency in DPR preparation, road geometry and safety provisions, while improving operational efficiency and reducing disruptions on high-speed corridors.

One of the key changes is the introduction of additional safety provisions suited to roads carrying high-speed traffic. The guidelines prescribe advance notification of highway exits and entries so that motorists have adequate time to anticipate and safely negotiate access and exit points, the ministry of road transport and highways (MoRtH) said in a statement.

The plan designs highways based on how many vehicles will use them. Corridors carrying up to 15,000 vehicles will have a four-lane highway and four-lane structures, with a proposed corridor width of 60 metres, the guidelines said. Corridors with traffic between 15,000 and 25,000 vehicles will have four-lane highways and six-lane structures with a width of 70 metres, it added.

For traffic between 25,000 and 40,000 vehicles, the guidelines prescribe a six-lane highway and six-lane structures, also within a 70-metre corridor width.

Limiting direct access

The guidelines also seek to limit direct access to high-speed highways by requiring interchanges and ramps at important road crossings. These will be provided at crossings with expressways, national highways, state highways and important arterial roads that generate substantial traffic.

Connectivity to major traffic-generating destinations—including ports, airports, multimodal logistics parks, industrial areas and major tourist destinations—will also be provided through interchanges.

NHAI has also prescribed a physical barrier to strengthen access control. A 1-metre-high boundary wall will be constructed along the outer edge of the corridor to prevent encroachments, unauthorized entry and stray cattle from entering the highway.

The new framework will apply to both greenfield projects and existing highway stretches being upgraded into access-controlled corridors. By establishing common parameters for traffic assessment, lane configuration, structures, interchanges and access control, NHAI aims to bring greater consistency to project planning while supporting the expansion of India’s high-speed highway network and the government’s Viksit Bharat 2047 road map.

About the Author

Subhash is the infrastructure editor at Mint and tracks the momentous developments taking place in the space that is fast changing the Indian landscape. He finds reporting to be a passion that provides the necessary adrenaline rush and keeps you going.