Building a robust and resilient road infrastructure is essential for long-term socio-economic development of the country. Road infrastructure is required to provide faster mobility together with safety, logistic efficiency, and user convenience, and it should also be sustainable in the long run. Conventionally, road construction is associated with the depletion of natural resources such as stone, fertile soil, sand, etc., felling of trees, emission of greenhouse gases, etc. Resolving these trade-offs is essential to achieve sustainable development.
To cite one example, one lane-km of road construction requires 20,000 tons (approx.) of good quality stones. Further, it is estimated that the construction of every lane-km of National Highway generates CO2 emissions to the tune of 24–30 tonnes per year. Under PM Vision for Green Future & Net Zero, India has set ambitious targets of achieving "net zero" by 2070.
Therefore, to conserve the limited reserves of natural resources as well as minimize the emission of greenhouse gases, the Ministry of Road Transport and Highways (MORTH), under the visionary leadership of the Hon’ble Prime Minister and the able leadership of the Hon’ble Minister of Road Transport & Highways, has strategized its planning, design, construction, and maintenance of highways based on the following principles:
- Optimization of design using newmaterials,processesandtechnology resulting in materialsavings, longer life, acceleratedconstruction,etc.
- Minimize consumption of naturalresources
- Focusonlocallyavailablematerials
- Useofeco-friendlyalternatematerial
- Reduce,reuseandrecycleofwastematerials
- Conservation of water, soil, flora&fauna,etc.
- Adoptionofgreenconstructionpractices
- Useofefficientandenvironmental friendlyconstructionequipmentandmachineries
- Conservationofenergy
- Landscapingandplantation
- Prevention and control of emission of GHGs,water pollution, ambientnoise level, soil erosion & pollution, handlingand disposal of volatile, solid &liquidwaste
- Evaluationbasedonlife-cyclecosting
A few landmark achievements in use ofsuch materials, technology, processes indifferent National Highway projects to bring about sustainable development can be summarised as under:
- Ultra-HighPerformanceFiberReinforcedConcrete(UHPFRC)for long span bridge (65 Nos. ofbridgesconstructed/underconstruction with UHPFRC).
- Processed Steel Slag-(2.6 millionMTused)
- WastePlasticinbituminousmixes (2830km roadconstructed)
- InertmaterialofMunicipalLandfill(2.4millionMTused)
- BambooCrashBarrier (8.5km)
- Transplantationofuprootedtrees(70,000Nos.)
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Materials/technology such as soil stabilization, precast concrete elements, high-performance bituminous mixes, various types of geosynthetics, natural mats like coir/jute, recycling of existing bituminous pavements, full-depth reclamation, reuse of tunnel muck/landslide materials, use of construction & demolition waste, bio-bitumen, fiber-reinforced polymer rebars in replacement of steel bars for reinforced concrete, etc., are being used in different NH projects to varying scales.
Typically, the 135 km long Eastern Peripheral Expressway developed by NHAI can be considered a model case for a green highway project as it minimizes the carbon footprint in manifold ways.
- GenerationofSolarPower:Capacityof4MW.
- DripIrrigationforplants
- Extensive plantation: 6 lakhtreesplanted
Green National Highways Corridor Projects (GNHCP), being implemented with the assistance of the World Bank, is also another example of the use of sustainable technologies. Seven stretches of National Highways involving 23 construction packages, with a total length of 783 km, have been taken up under GNHCP. Green materials/technology such as coir/jute mat, hydroseeding, interlinked chain mesh with green strips, bamboo plantation, vetiver grass, hedge brush layering, recycling, etc., are being used in the said project.
MoRTH has been continuously striving to evaluate the performance of such materials and technology measures in terms of saving carbon footprints, strength, durability, and serviceability. While the performance of materials, processes, and technologies now being used or attempted need to be consolidated, continued efforts are being made to identify and develop new ones in a committed manner.
Report of TERI
Written by Sh. Dharmananda Sarangi, DG (Road Development) & Special Secretary, MoRT&H and Sh. Bidur Kant Jha, Director (New Technology, MoRT&H
