Indian Road Infrastructure

Standards – 2025 Edition

Shaping India’s Roads with Precision and Policy

The geometric design of India’s highways and urban roads adheres to a precise set of guidelines that ensure both functionality and safety. Rural highways and expressways must conform to parameters such as Stopping Sight Distance (SSD), Headlight Sight Distance (HSD), and critical geometric components like minimum curve radius, superelevation, and gradient transitions—defined in IRC:SP:99-2013 and IRC:SP:23-1983. Urban roads follow IRC-86:2018, which classifies roads into arterial, collector, and local, dictating lane widths, utility clearances, and pedestrian/cyclist pathways. These standards are legally binding and are a prerequisite in every approved government or PPP-funded road project in India.

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Right Width, Right Way

Uniform carriageway and lane widths are the unsung backbone of safe and efficient transport systems. Indian standards mandate precise dimensions depending on road type and function. Rural roads like Other District Roads (ODR) and Major District Roads (MDR) must maintain 3.70 meters per lane, ensuring safe passage for vehicles in less congested zones. National Highways follow a slightly wider standard—3.75 meters for single lanes and 7.0–7.5 meters for dual lanes—to accommodate high-speed traffic. Urban streets adhere to IRC-86:2018, with each lane typically 3.5 meters wide, scaling up to 14 meters for four-lane roads. These dimensions are enforced through MoRTH and IRC approvals, built into legal and contractual obligations, and routinely audited to maintain compliance.

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Layered Strength from Ground to Asphalt

The durability and longevity of a road begin beneath the surface. India’s pavement construction adheres to specifications outlined by the Ministry of Road Transport and Highways (MoRTH) and detailed IRC codes. These define every layer from the sub-base to the final surface. Sub-base layers typically consist of Water-Bound Macadam (WBM) or Wet Mix Macadam (WMM), providing foundational strength and drainage. Over this, flexible pavements are built using Dense Bituminous Macadam (DBM) and Bituminous Concrete (BC), while rigid options use cement concrete, in line with IRC-15-2017 and IRC-SP-15-2015. The design of new bituminous roads aligns with IRC-37-2019. These specifications are not merely guidelines—they are mandatory, legally enforceable benchmarks ensuring safety, resilience, and quality in all public infrastructure.

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Visibility That Saves Lives

Clear, standardized road markings and reflective studs are critical for nighttime navigation, safe lane discipline, and accident prevention. Under IRC:35-2015, white lines demarcate lanes, yellow lines restrict overtaking, and blue lanes indicate special-use zones like Bus Rapid Transit Systems (BRTS). These lines must use durable materials such as thermoplastic paint, solvent-based coatings, or preformed tapes that withstand weather and traffic stress. Complementing these are reflective road studs—commonly called “cat’s eyes”—crafted as per MoRTH Clause 804. These uni- or bi-directional studs reflect headlights, enhancing visibility around curves, intersections, and pedestrian zones. With a service life of 2–3 years, they are essential safety components, legally required on all public roads.

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Color-Coded Clarity on Every Route

India’s roadways communicate safety, regulation, and direction through a robust system of color-coded signage. Governed by IRC-67:2022 and the MoRTH signage manual, these signs use distinct colors for instant comprehension: blue backgrounds with white text for urban navigation, green signs with white letters for national highways, and red-bordered or red-filled signs for regulatory and warning purposes. Each color and symbol is meticulously standardized to prevent ambiguity and to provide quick, recognizable cues to drivers across language barriers. These signs are mandatory across all public roads, and their installation is a critical part of any new or upgraded infrastructure project.

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Safe Steps and Smooth Rides for All

Inclusive mobility is the foundation of modern road design. Indian urban infrastructure integrates dedicated facilities for pedestrians and cyclists under IRC-86:2018 and IRC-11:2015. Key features include pedestrian subways with a minimum 2.5-meter width and 2.75-meter clear height for smooth, safe flow. Accessibility ramps maintain a gentle gradient of 1:20 and feature flat landings for comfort and wheelchair use. High-volume intersections require elevators or escalators for added convenience. Cyclists benefit from clearly marked, segregated lanes within the road layout—ensuring protection from vehicular traffic. These standards are mandatory for all publicly funded smart city and urban development projects, making non-motorized transport a safe, viable choice.

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Connecting Distances with Strength and Flow

Bridges and culverts form the connective tissue of road networks, enabling seamless travel across rivers, canals, and terrain changes. Indian standards ensure these structures are not only strong but hydrologically sound. Structural and geometric designs follow IRC-005 to IRC-006 series, while drainage and waterway management is guided by IRC-056-2011 and slope protection by IRC-038-1988. Each culvert or bridge is uniquely identified using standardized numbering as per IRC-007-2017. Proper slope protection, scouring resistance, and discharge capacity are integral to long-term stability. These elements are mandatory for any sanctioned project, subject to technical vetting and approval by national and state authorities.

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Prevent, Protect, Preserve

Safety and longevity go hand in hand on India’s roads. MoRTH and IRC have laid out comprehensive safety and maintenance protocols to reduce accidents and extend infrastructure life. Key elements include rumble strips, crash barriers, and reflectors as per IRC-119-2015, providing tactile and visual warnings to drivers. For road upkeep, IRC-057-2018 mandates pavement rehabilitation techniques and crack sealing, while IRC-116-2014 outlines flexible pavement maintenance. These measures are legally binding in all maintenance contracts and monitored through audits and performance metrics. By prioritizing proactive upkeep, the framework ensures roads remain functional, safe, and cost-effective over time.

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From Blueprint to Blacktop – Governed by Law, Guided by Engineering

Behind every Indian road project lies a robust framework of legally binding technical standards. These MoRTH and IRC norms govern every phase—from conception and design to construction and upkeep. Whether it’s geometric design, material use, safety features, or sustainability metrics, compliance is non-negotiable for approval and funding. Public and PPP projects must align with these guidelines, and any deviation is allowed only through formal written approval by authorities like MoRTH, NHAI, or PWD. This systematic oversight ensures consistency, safety, and engineering integrity, turning blueprints into dependable infrastructure across India.

Rajendra Parekh Kalanidhi

1. #MoRTH – Ministry of Road Transport and Highways; oversees road infrastructure in India.

2. #IRC – Indian Roads Congress; sets technical standards and codes for road design and construction.

3. #NH – National Highways; main roadways connecting cities and states in India.

4. #SH – State Highways; major roads maintained by state governments.

5. #ODR – Other District Roads; rural roads connecting remote areas to main roads.

6. #MDR – Major District Roads; roads connecting district headquarters to important locations.

7. #DBM – Dense Bituminous Macadam; a layer in bituminous pavement providing strength.

8. #BC – Bituminous Concrete; the topmost smooth surface layer in flexible pavements.

9. #WMM – Wet Mix Macadam; a strong sub-base material used in pavement layers.

10. #WBM – Water Bound Macadam; traditional granular sub-base layer.

11. #CC – Cement Concrete; used in rigid pavements for long-term durability.

12. #SSD – Stopping Sight Distance; the minimum distance needed for a driver to stop safely.

13. #HSD – Headlight Sight Distance; the distance a driver can see ahead at night using headlights.

14. #PPP – Public-Private Partnership; collaborative road projects involving government and private sector.

15. #BRTS – Bus Rapid Transit System; dedicated lanes for efficient bus travel.

16. #ITS – Intelligent Transportation Systems; technology used to improve road safety and efficiency.

17. #NHAI – National Highways Authority of India; responsible for managing and developing NHs.

18. #PWD – Public Works Department; state-level agency responsible for infrastructure projects.

19. #SP – Special Publication; IRC documents containing design guidelines (e.g., IRC-SP-15).

20. #IS – Indian Standard; national specifications for materials and construction practices.

21. #IRR – Intermediate Ring Road; urban road class used in city planning.

22. #TCD – Traffic Control Devices; includes road signs, signals, and markings.

23. #LHS – Left Hand Side; typical driving side in India.

24. #RHS – Right Hand Side; opposite side in driving design references.

25. #ADT – Average Daily Traffic; a measure of vehicle flow on a road segment.

26. #ADTQ – Average Daily Truck Traffic; used in pavement and capacity design.

27. #LOS – Level of Service; a grading system for road capacity and user experience.

28. #AADT – Annual Average Daily Traffic; average daily traffic over a year.

29. #ROW – Right of Way; the total land area acquired for road construction.

30. #KM – Kilometer Marker; signs showing distance traveled or remaining on highways.