NHAI has rolled out new design rules for four‑ and six‑lane access‑controlled highways, making one‑metre cattle walls mandatory and linking lane width to projected traffic volumes.
The rules apply to both greenfield and brownfield projects but exclude expressways, and they prescribe ramp interchanges at major crossings and advance warnings before exits to give drivers more time.
Lane numbers and width will scale with traffic volume: up to 15,000 vehicles per day gets four lanes and a 60‑metre width; 15,000‑25,000 vehicles gets four lanes and six‑lane structures at 70 metres; 25,000‑40,000 vehicles gets six lanes and a 70‑metre width.
The move follows a lack of standard design norms that had created inconsistencies in Detailed Project Reports, prompting the Ministry of Road Transport to stress that the new framework will enforce uniform safety and technical requirements across the expanding network.
These guidelines are part of a broader vision to build 50,000 km of access‑controlled corridors by 2047, linking airports, ports and logistics hubs with dedicated ramp interchanges.