Key Details
The guidance spans traffic estimates, construction methods and the Detailed Project Report (DPR) used to plan a corridor.
Coverage: Upcoming four- and six-lane high-speed national highways on new alignments (greenfield) or existing corridors (brownfield). Expressways are excluded.
Traffic: Forecasts must consider existing and diverted vehicles, future freight demand, economic activity and toll data.
Construction: Guidelines provide for Automated and Intelligent Machine-aided Construction (AI-MC) of embankments and pavements under applicable ministry guidance.
Tolling: Corridor plans must make provision for Multi-Lane Free-Flow (MLFF) tolling, intended to let vehicles pass without stopping at a toll plaza.
Water and planting: DPRs must identify drainage and rainwater-disposal arrangements. Landscaping must reflect local conditions, with drip irrigation on highway medians.
Traffic Forecasts Must Look Beyond Current Road Use
NHAI wants planners to account for traffic that a new corridor may draw from other roads and for freight generated by future commercial activity. Toll records and other reliable data are to inform those forecasts. The resulting estimates shape decisions about corridor capacity before construction begins.
Construction Methods and Tolling Enter Corridor Plans
The guidelines provide for machine-aided work on embankments and pavements to improve construction consistency, accuracy and monitoring. They also require provision for free-flow tolling in the design of upcoming corridors. The release concerns planning for that system; it does not announce that MLFF is operating on these highways.
Drainage and Planting Are Planned from the Start
The DPR must identify where rainwater from the highway and surrounding areas will go. It must address vulnerable locations such as underpasses and depressed medians, and provide water-harvesting structures where suitable.
Planting is also to be designed for the local climate and terrain, including suitable spaces in medians, interchange loops and below flyovers. Median drip irrigation is intended to reduce water use and support maintenance.
Policy Relevance
Project appraisal: Traffic estimates and drainage plans now become more important tests of a proposed corridor’s design, not details to resolve during construction.
Coordination beyond the road boundary: Drainage arrangements must account for water arriving from, and leaving for, surrounding areas. Their effectiveness depends on whether the DPR reflects conditions beyond NHAI’s roadway.
Checking results: Once corridors open, observed traffic, waterlogging and construction quality can show whether the planning assumptions and prescribed methods worked.
Relevant Question for Policy Stakeholders: How will NHAI compare traffic, drainage and construction outcomes on completed corridors with the assumptions and methods set out in their project reports?
Follow the Full News Here: NHAI Guidelines for High-Speed National Highway Corridors