NHAI Sets New Design Standards for High-Speed National Highways

New Rules Set Uniform Standards for Access-Controlled Corridors

The National Highways Authority of India (NHAI) has issued new guidelines for access-controlled high-speed national highways. The framework standardises lane planning based on traffic projections and adds safety provisions for smoother vehicle movement.

The guidelines will apply to all upcoming four- and six-lane greenfield and brownfield high-speed access-controlled national highways.

Uniform Standards For Highway Projects

NHAI said the framework will bring greater uniformity to Detailed Project Reports (DPRs) for these corridors. It will also align technical standards, strengthen road safety and improve highway operations.

Previously, separate standards were not available for planning and designing access-controlled high-speed national highways, except expressways. This resulted in variations in the standards used while preparing DPRs.

The new framework fills this gap through a common set of technical and safety requirements.

Traffic Will Determine Lane Configuration

The guidelines link highway configuration with projected traffic volumes. Different traffic ranges will determine the number of lanes, structure configuration and corridor width.

• Up to 15,000 vehicles: Four-lane highway, four-lane structures and 60-metre width.
• 15,000–25,000 vehicles: Four-lane highway, six-lane structures and 70-metre width.
• 25,000–40,000 vehicles: Six-lane highway, six-lane structures and 70-metre width.

New Safety Measures For High-Speed Traffic

The framework includes additional safety provisions specifically for high-speed traffic conditions.

It requires advance notification for exits and entries. This will give road users more time to identify upcoming access and egress points and navigate them safely.

One-Metre Boundary Wall For Access Control

NHAI has also mandated a one-metre-high boundary wall along the outer edge of the highway corridor.

The provision aims to restrict unauthorised access and prevent stray cattle from entering high-speed corridors, according to the official statement.

Ramps Planned For Major Road Connections

Interchanges with ramps will be provided where these highways cross expressways, national highways, state highways and important arterial roads.

The provision will also cover roads connecting major destinations that generate substantial traffic. These include ports, airports, multi-modal logistics parks, industrial areas and key tourist spots, the statement said.