Classification of Roads in India

Roads are the lifelines of modern civilization, facilitating the movement of people, goods, and services. They play a crucial role in economic development, social integration, and overall connectivity. Road classification is essential for planning, design, construction, maintenance, and management of a country’s transportation infrastructure. This article explores the various classifications of roads based on function, administration, access control, pavement type, terrain, traffic volume, usage and design standards.

What is the Purpose of Road Classification?

Road classification is the way we organize roads into different groups based on their function and use. This helps city planners, engineers, and government bodies manage roads better.

Design and Planning

Classifying roads into various categories makes it easy for the given government bodies to decide where and how to build the roads for better connectivity. Often Highways are designed differently than the local streets or city roads as both the roads serve different purposes.

Traffic Management

Classifying roads into various groups helps authorities control how traffic moves throughout the network.

Busy main roads require different traffic management approaches compared to local streets due to their higher traffic volumes and the need to keep the traffic running smoothly.

Safety and Regulations

Different roads require different safety features tailored to their specific purposes. Highways might have barriers and wide lanes to elevate safety standards at high speeds, while local roads often have crosswalks and stop signs to protect pedestrians and manage traffic flow within residential areas.

Different speed limits and rules are used for different roads to keep people safe and match the road’s purpose.

Heavy trucks may be allowed only on certain roads for big vehicles, keeping them out of residential areas to keep neighborhoods peaceful.

Resource Allocation For Road Projects

Classifying roads enables governments to decide where to allocate funds for road construction and repairs more effectively. Important roads that serve many people might receive more funding due to their higher usage and significance in the transportation network.

Land Use Planning

Classifying roads helps in deciding how land around them is used. Major roads might be located next to shopping centers and commercial buildings due to their capacity to handle heavy traffic, while local roads are often situated in residential areas, providing access to homes and community facilities.

Road Classification Methods

• Functional Classification of Roads
• Classification Based on Traffic Volume
• Classification By Surface Type
• Classification Based on Nagpur Plan Road Network
• Classification Based on the Third Road Development Plan
• Classification of Urban Roads

Functional Classification of Roads

Roads are primarily classified based on their function in managing traffic flow and offering access. The main categories are:

• Arterial Roads
• Collector Roads
• Local Roads

Arterial Roads

Arterial roads are big roads designed for fast and long-distance travel. They connect major towns, cities, and regions. These roads have high-speed limits and few stops or interruptions, which helps keep traffic moving smoothly.

Arterial roads have limited direct access to homes or businesses to avoid slowing down the traffic. Examples of arterial roads include highways and main roads you use to travel between cities.

Collector Roads

Collector roads are medium-sized roads that gather traffic from local streets and lead it to arterial roads. They help move traffic from neighborhoods to larger roads.

Collector roads have moderate speed limits and provide some access to homes and businesses. They balance the need to move traffic efficiently with the need to allow property access. For example, a road that connects residential areas to the main highway is a collector road.

Local Roads

Local roads are small roads within neighborhoods. They provide direct access to homes, schools, parks, and local businesses.

Local roads have low speed limits and many driveways and intersections. They’re designed for short trips and local traffic. The street where your house is located is likely a local road.

Classification of Roads Based on Traffic Volume

Based on traffic volume the roads are classified as follows :

Type of Road	Vehicles Per Day
Very Heavy Traffic Road	Above 600
Heavy Traffic Road	251 – 600
Medium Traffic Road	70 – 250
Light Traffic Road	Below 70

Classification By Surface Type

Roads can be classified based on the type of surface material used in their construction. The surface type affects the road’s durability, cost, and suitability for different traffic conditions. Understanding these classifications helps in planning and building roads that meet specific needs.

Paved Roads

Paved roads are roads that have a hard, smooth surface made from durable materials like asphalt or concrete. These roads provide a comfortable and safe driving experience and are suitable for all types of weather and traffic condition.

1. Bituminous Road (Flexible Pavements)

• Bituminous road are paved road surfaced with bitumen, a sticky, black substance derived from crude oil. The surface layer is a mixture of bitumen and aggregates like sand and gravel.
• It is called flexible pavement because the road surface can bend or flex under traffic loads without cracking. This flexibility helps distribute the weight of vehicles over a wider area.
• Bituminous road is commonly used in cities, towns, and highways. They are popular because they provide a smooth driving surface and are relatively quick and cost-effective to construct.

2. Concrete Road (Rigid Pavements)

• Concrete roads are paved with a surface made of concrete, which is a mixture of cement, water, sand, and aggregates. Once laid, the concrete hardens to form a rigid and strong surface.
• It is called rigid pavement because the concrete surface does not flex under traffic loads. The rigidity of the concrete slab helps distribute the load over a larger area beneath it.
• Concrete roads are used in places with heavy traffic loads, such as major highways, airport runways, and industrial areas. They are durable and have a long service life, though they are more expensive to build initially.

Unpaved Roads

Unpaved roads are roads without a hard surface layer. They are made from natural materials available on-site, like gravel or earth. These roads are less costly to build but may be less comfortable to drive on and can be affected by weather conditions.

1. Gravel Road

• Gravel road have a surface layer made up of locally available gravel or crushed stone. The gravel is spread over the prepared roadbed and compacted to form a stable surface.
• They are typically found in rural areas, agricultural regions, or low-traffic zones where paving is not economically practical.
• Gravel road are still widely used today. They are cost-effective for areas with low traffic volumes and can be maintained relatively easily.

2. Earth Road

• Earth road are constructed from the natural soil found at the site. The roadbed is shaped and compacted to form a passable surface.
• Earth road are often used in remote or undeveloped areas with very low traffic. They might also serve as temporary roads during construction projects.
• Earth road is still in use, especially in rural or undeveloped regions. However, they can be difficult to use during bad weather (specifically in rainy season) and require regular maintenance.

Classification Based on Nagpur Plan Road Network

The Nagpur Plan (1943) was India’s first attempt to classify roads systematically. The Nagpur road plan classifies the road in India based on location and function into following 5 categories :

• National Highways (NH)
• State Highways (SH)
• Major District Highways (MDR)
• Other District Roads (ODR)
• Village Roads (VR)

National Highways (NH) :

The main highways running through the length and breadth of India, joining major parts, capital of states, large industrial and tourist centers, foreign highways including roads required for strategic movements for the defence of India etc. are known as National Highways (NHs).

The numbering of National Highways in India is done by the Ministry of Road Transport and Highways (MoRTH). This government body is responsible for the development, maintenance, and regulation of National Highways in India.

For example:

• Amritsar- Ambala- Delhi Road – NH44
• Delhi- Agra- Kanpur- Kolkata Road – NH19
• Agra- Mumbai Road – NH47
• Madurai and Rameswaram – NH87

The responsibility of construction and maintenance of these roads lies with the central government. Central Government holds the responsibility of construction and maintenance of these roads.

State Highways (SH) :

The highways linking up with the national highways of adjacent states, district headquarters and important cities with the states are known as State Highways (SHs).

The geometric design specifications and design speed for NH and SH are same. These highways serve as arterial routes of traffic from district road within the state.

The responsibility of construction and maintenance of these roads lies with state government. However, the central government gives grant for development.

Major District Roads (MDR) :

The important roads within a district serving areas of production and markets and connecting these places with each other or with the main highways are known as Major District Roads (MDRs).

The responsibility of construction and maintenance of these roads lies with District Authorities. However, the state government gives grant for development of these roads.

Other District Roads (ODR) :

The roads serving rural areas of production and providing them with outlet to market centers, tahsil headquarters, block development headquarters, railway stations etc. are known as Other District Roads (ODRs). This have lower design specification than MDR.

Village Roads (VR) :

The roads connecting villages or group of villages with each other or with the nearest road of higher category are known as village roads.

These roads are very important from the rural area development point of view. They are generally un-metalled with single lane width of stabilized soil or gravel. The responsibility of construction and maintenance of these roads lies with the local district authorities.

Classification Based on the Third Road Development Plan

According to the Third Road Development Plan (1981-2001), roads in India are classified into three major systems for transport planning, functional identification, and prioritization. The roads are classified into three classes based on the hierarchy of their importance.

• Primary System (Class 1 Roads)
• Secondary System (Class 2 Roads)
• Tertiary System (Class 3 Roads)

Primary System (Class 1 Roads)

• Expressways (EX)
• National Highways (NH)

The roads which are within this Class 1 Provide high-speed corridors for long-distance travel, connecting major urban centers and economic hubs across the country. Roads within primary system class have high design standards, multiple lanes and advanced safety measures. They are built to handle large amounts of traffic, including commercial and passenger vehicles, and ensure smooth and safe transportation over long distances.

Secondary System (Class 2 Roads)

• State Highways (SH)
• Major District Roads (MDR)

The roads classified under Class 2 serve medium-distance travel needs and connect smaller towns, districts, and regional centers to the primary road network. These roads have moderate design standards and may have fewer lanes compared to Class 1 roads. Class 2 roads facilitate regional connectivity and support intra-state travel, playing a crucial role in the movement of people and goods within a state.

Tertiary System (Class 3 Roads)

• Other District Roads (ODR)
• Village Roads (VR)

Class 3 roads provide direct access within communities and rural areas. They connect villages, residential neighborhoods, farms, and minor localities to the higher-order roads. Typically, these roads have basic design standards and are constructed with a focus on providing essential access rather than high-speed travel.

Classification of Urban Roads :

The road system within urban areas are classified as urban roads. The urban authorities are responsible to take care of these roads.

Generally the urban roads other than the express ways are classified as :

• Arterial Roads.
• Sub- Arterial Roads.
• Collector Streets.
• Local Streets.

Arterial Roads :

In urban areas, arterial roads are main streets that carry a lot of traffic across town. They move large volumes of traffic efficiently within the city. These roads have multiple lanes and higher speed limits compared to collector or local streets. There are fewer interruptions like traffic lights or stop signs, and they have limited access to nearby properties. An example is a major city street that connects different parts of the city.

Sub- Arterial Roads :

Sub-arterial roads are important city roads that are not as large as arterial roads. They connect arterial roads to collector streets. These roads handle moderate amounts of traffic and have more access points to properties than arterial roads. They serve as links between main roads and smaller neighborhood streets.

Collector Street :

Collector streets collect traffic from local streets and direct it to bigger roads like sub-arterial or arterial roads. They help people get from their neighborhood streets to the main roads. These streets have moderate speed limits and provide a balance between moving traffic and providing access to homes and businesses. For example, a street that runs through a neighborhood and connects local streets to the downtown area is a collector street.

Local Street :

Local streets are the small streets within residential areas. They provide direct access to homes, local shops, and community facilities. These streets have low speed limits to ensure safety for pedestrians and cyclists. There are many driveways and intersections. They’re designed primarily for local traffic, and they make up the majority of streets in a neighborhood.

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