New Guidelines for Shoulder Widths on National Highways Announced

The Ministry of Road Transport and Highways (MoRTH) has issued new guidelines regarding the width of shoulders—both paved and earthen—for National Highways. This directive, detailed in a recent circular, updates previous specifications to enhance safety and functionality on these roads.

Key Points from the New Guidelines:

Revised Shoulder Widths:

i) Existing Guidelines: According to the Manual of Standards and Specifications for two, four, and six-lane highways (IRC:SP:73-2018, IRC:SP:84-2019, IRC:SP:87-2019), paved shoulders should be 2.5 meters wide and earthen shoulders should be 1.5 meters wide for highways in open country with isolated built-up areas in open and rolling terrain. Previously, Circular No. EFile/RW/NH-33044/22/2020-S&R (PGB) dated July 17, 2020, mandated a reduced width of 1.5 meters for paved shoulders and 1.0 meter for earthen shoulders on two-lane highways in similar terrains.

ii) Updated Specifications: The latest standards, as outlined in IRC: 73-2023, specify a paved shoulder width of 1.5 meters and an earthen shoulder width of 1.0 meters for two-lane highways. For four, six, and eight-lane highways, the paved shoulder width is set at 2.0 meters and the earthen shoulder at 1.5 meters.

iii) Purpose of the Updated Widths: The new guidelines aim to provide sufficient lateral support for pavements, offer storage space for errant or broken-down vehicles, and allow for the placement of safety barriers. These changes are intended to be cost-effective while ensuring road safety and functionality.

Culvert and Bridge Specifications:

i) Culverts: The clear width of culverts must match the overall roadway width, including carriageway, paved and earthen shoulders, and median.

ii) Bridges and Grade Separated Structures: The deck width of bridges and other elevated structures should be consistent with the roadway width of their approaches. Footpaths on bridges should have RCC crash barriers separating them from the carriageway and pedestrian guard rails on the outer edges.

These updated provisions will be applicable to all new projects for which bids are submitted within 60 days following the release of this circular. The revised guidelines will supersede the previous Ministry/IRC Manuals/IRC: 73:2023 standards.

All parties concerned are required to incorporate these changes into their planning and construction practices.

This updated directive reflects the Ministry’s commitment to improving road infrastructure safety and functionality while adapting to evolving needs in highway design. It aims to enhance road safety and ensure uniformity across National Highway projects.