Why bitumen is needed for roads, the situation today

Bitumen is a black, waterproof and highly viscous material that holds the materials that make up roads — concrete, gravel, etc. — together. It is derived from crude oil, much like LPG, petrol, and diesel.

Imports have already taken a hit after the West Asia war began on February 28, with road construction companies and contractors raising concerns over low supplies and increasing prices with the National Highway Authority of India (NHAI) and state road agencies.

According to the Ministry of Petroleum and Natural Gas (MoPNG) data, India imported 2.36 lakh tonnes of bitumen in April 2026, compared to 2.97 lakh tonnes imported in April 2025 and 2.74 lakh tonnes imported in April 2024. Similarly, domestic bitumen consumption has also declined, signalling a slowdown in road construction. A total of 5.80 and 5.19 lakh tonnes was used in April and May 2026 — almost 33% lower than the 8.62 and 8.57 lakh tonnes consumed in April and May 2025. It was also lower than the same period in 2024.

India requires almost 90 lakh tonnes of bitumen annually. Of this, around 54 lakh tonnes are produced domestically in the refineries of oil companies like IndianOil and Bharat Petroleum. The shortfall is met by imports from West Asia. Over 99% of India’s bitumen imports come from Iraq, UAE, Iran, Oman and Bahrain.

How bitumen is produced

Crude oil is essentially a natural mixture of hydrocarbons such as methane, ethane and propane. It is heated at different temperatures to extract usable products.

In a refinery, crude oil is first heated to about 350-400°C to separate LPG, petrol, kerosene, diesel, jet fuel, and similar products. After this process, a large amount of residue collects at the bottom of the distillation column, which is called atmospheric residue. The huge tower often seen in photos of refineries is the distillation column, while the large cylindrical tanks around it store products after distillation.

This residue is then sent to a vacuum distillation unit, where the pressure is reduced to much lower than atmospheric pressure, so that very heavy hydrocarbons (vacuum gas oils) can vaporise at a lower temperature.

Under controlled conditions, the residue is further heated to 380-425°C and heavy Vacuum Gas Oils are removed. What remains is vacuum residue, also known as bitumen. It is further blended and adjusted to meet different viscosity specifications like VG-10, VG-30, VG-40, which are road-paving bitumens.

According to analysts, one tonne of crude oil can result in 3-8% (30-80 kg) of bitumen, depending on the type of oil. Light crude yields more petrol and diesel but very little bitumen. Heavy crude results in more vacuum residue and, therefore, more bitumen. It is stored in a tank at 150-170°C to keep it pumpable.

Dr Zafar Khan, President of the Highways Investor Association, said, “India buys oil from Russia as well, but it is light, and its viscosity level is low… Crude oil from Iraq, Saudi Arabia and the UAE is heavier and produces more bitumen. Thus, the Strait of Hormuz has become critical for roads, not only because of direct bitumen imports but also because of the crude oil passing through it, which contributes to most domestic bitumen production,” Khan told The Indian Express.

The import-consumption mismatch

India was not always as dependent on imports. The change has been driven by the mega road projects undertaken within the last decade, through schemes like Bharatmala (for enhancing road connectivity via expressways and economic corridors) and PMGSY.

National Highways have grown from 91,287 km in 2014 to 1.47 lakh km currently (a 61% increase), while the length of expressways increased from 93 km to 3,052 km. However, domestic bitumen production has not kept pace and has remained almost the same over the last 10 years. Imports have more than doubled, and consumption increased by almost 50% (see box).

Bitumen consumption and domestic production (lakh metric tonne)

Source: Petroleum Planning and Analysis Cell, MoPNG 

According to data available with the Petroleum Planning and Analysis Cell of MoPNG, bitumen imports began in 2001-02, at around 9,000 tonnes. A significant increase was recorded in 2013-14, when 2.46 lakh tonnes were imported — more than double the previous year’s import volume. This doubled again by 2014-15, reaching 5.17 lakh tonnes, and continued increasing.

Another major jump came in 2019-20, when imports rose to 16.30 lakh tonnes. India’s bitumen imports peaked in 2023-24 at 32.44 tonnes, before declining (see box). India is now spending between Rs 9,000 and 10,000 crores on bitumen imports annually.

Bitumen imports 

Source: Petroleum Planning and Analysis Cell, MoPNG 

Force majeure

The Ministry of Road Transport and Highways (MoRTH) has granted relief measures of force majeure and price adjustment to highway contractors in light of war-related disruptions. In its June 5 circular, the ministry said that for project delays linked to the conflict, contractors can claim force majeure clauses to receive two to four months of relaxation without penalty.

The ministry has also provided a cost-escalation compensation mechanism, or price adjustment, to account for a surge in fuel prices and construction material costs, as well as logistics expenses. However, contractors availing themselves of relief under the price-adjustment circular will not be eligible for force majeure relief.

Khan said that those constructing roads under PMGSY and small-Engineering, Procurement and Construction (EPC) projects are facing the most difficulty: “While everybody is in distress, the larger highway contractors are better equipped to deal with the situation. The existing crude can be recycled for the bitumen. The government should try to protect smaller contractors from an increase in prices. The price of one tonne of bitumen had shot up to Rs. 80,000 from Rs. 40,000.”

A senior NHAI official said, “We are taking all the possible measures to continue the uninterrupted supply of bitumen.”

Bio-bitumen as an alternative

To address stagnant domestic production and increasing imports, CSIR-Central Road Research Institute (CRRI) and CSIR-Indian Institute of Petroleum (IIP), Dehradun, have jointly developed a bio-bitumen technology which uses rice straw (parali) to produce Bio-oil. This is further blended to produce bio-bitumen.

The technology was unveiled on January 6. So far, three pilot test sections on National Highways have been laid to assess the suitability of bio-bitumen in road construction.

According to CRRI, an earlier bio-bitumen trial was successful in October 2024 on a 100-meter stretch of NH-6 (Jorhat-Shillong section). It was also used on a one-km stretch in Manchar on the Nagpur-Jabalpur National Highway.

The government is projecting it as a dual solution to reduce import dependence and address winter pollution in northern India, where stubble burning is a contributor. It has also claimed that a 15% blending of bio-bitumen would save around Rs 4,500 crore in foreign exchange.

However, commercial production is challenging and has yet to begin. CSIR-CRRI has invited Expressions of Interest (EOIs) from eligible Indian firms. The government has also sanctioned two research projects, one each to IIT Roorkee and CSIR-CRRI & CSIR-IIP, to assess the long-term performance of pavement constructed with bio-bitumen.