Sustainable road development can balance economic growth with environmental protection and social inclusion.
More than 400 million people in Asia and the Pacific lack all-weather access to markets and essential services. Moreover, the region’s emerging economies have some of the lowest per capita road lengths in the world. Road transport that is safe, inclusive, low-carbon, and climate-resilient is crucial for reducing poverty and promoting green, inclusive, and sustainable growth.
To foster development and ensure accessibility for all, these countries need to invest substantially in road and other transport infrastructure and enhance transport efficiency. The Asian Transport Outlook estimates that the region will need to build 8 million kilometers of roads by 2030. Furthermore, the costs of maintaining and operating road networks in the region are expected to surpass the costs of new road construction by 2030.
However, roads also have significant environmental and social impacts that need to be addressed.
For instance, road transport is a major source (18%) of global energy-related CO2 emissions and has been leading the increase in carbon emissions in recent decades. Across the world, growth in transport sector emissions is highest in Asia, driven largely by growing demand for road passenger and freight transport.
Road development can also alter the natural hydrology of landscapes, causing springs to dry up in mountain areas, waterlogging to increase in coastal areas, and floods to be amplified as roads disrupt the natural drainage. Roads are also estimated to increase erosion in catchments by 12-40%, which affects soil fertility and water quality.
Road development can fragment and degrade habitats of wildlife, plants, and insects. Roads are among the top three causes of animal mortality in many countries, and also facilitate the spread of invasive species and diseases.
Road construction and operation also have impacts on the well-being of people. For example, dust and vehicle emissions can have major impacts on air quality. The Asian Transport Outlook estimates that 76% of global deaths related to breathing particulate matter happen in Asia and the Pacific. Roads also contribute to urban heat islands, which raise temperatures in cities and affect human health and comfort.
Building and rehabilitating roads consumes a large amount of construction materials, which account for 30-40% of all the materials used in construction projects. The demand for these materials has grown much faster in Asia than in the rest of the world. In the last decade, Asia’s demand has increased by 64%, while the global increase was only 17%. This creates challenges for the sustainability of natural resources and the management of waste and pollution.
The huge impacts of road development require a new approach to how roads are planned, constructed, and managed. Roads should not only serve transportation needs, but also support other objectives such as enabling climate and disaster resilience, improving quality of life, promoting sustainable land and water use, reducing disaster risk, strengthening ecosystems, minimizing pollution, sourcing materials responsibly, and enhancing inclusive economies.
To balance economic, social, and environmental objectives and make roads in Asia and the Pacific greener, a holistic and integrated approach to road planning, development, and maintenance and operations is needed. Green Roads can leverage high demand for road investments to create a win-win situation for both development and environment.
To achieve this, the following actions are needed:
- Protect biodiversity and ecosystems by avoiding or minimizing road impacts on natural habitats and wildlife and creating road features that allow animal crossings and biodiversity conservation, such as verges, underpasses, or bridges.
- Enhance climate and disaster resilience by designing roads and managing road networks that can withstand extreme weather events, minimize accumulation of heat, and reduce disaster risks.
- Contribute to the transition to low-carbon economies by adding and provisioning for more charging stations for electric vehicles to support e-mobility, promoting modal shifts to less carbon-intensive travel modes such as walking and cycling, and using recycled and innovative materials that lower carbon emissions and energy consumption to minimize the carbon footprint of road construction.
- Use sustainable procurement and circular economy practices including selecting lower carbon construction materials and equipment, reuse and recycle waste, and prolong the life span of roads.
- Improve water management by using roads to collect, store, and distribute water for irrigation and other needs.
- Enhance quality of life by minimizing road pollution and improving access to markets and social services.
Green roads can enhance both development and environment by minimizing environmental impacts of roads whilst fostering sustainable growth.