Authorities will no more scratch their head for the disposal of waste materials. Odisha has set an example in India by adopting green technologies in road construction and using waste materials like fly ash, stone dust, morrum, blast furnace slags etc which cause severe health and environmental hazards if left as such.
The move has not only reduced the cost of road construction, it has also prevented the negative impact on the environment. The premier institutes like National Institutes of Technology (NIT) and Indian Institute of Technology (IIT) have appreciated the state for using green technologies.
The Ministry of Rural Development (MoRD) and Panchayatiraj have falicitated the state for adoption of new technology for a length of 562 kilometers during 2016-17.
The popular Government addresses accessibility issues by providing all road weather connectivity to unconnected habitations in rural areas. To accomplish this vision, Odisha wants to construct 65,000 kilometers roads in 10 years.
Availability of natural resources for construction of low volume roads is a major concern. Huge quantity of sub base materials and Water Bound Macadam (WBM) materials it needs. The materials being used have huge financial involvements and may not be economically viable.
On the other hand, the state has huge deposit of fly ash, a waste by-product of steel plants and thermal power plants, stone dust, morrum, blast furnace slag and so on.
Green technology for construction of 4500 kilometers of roads
The state is now adopting green technology for construction of about 4500 kilometers of roads using Cold mix Technology, Roller Compacted Concrete Pavement, Paneled Concrete, Cell filled Concrete, Iron Slag for sub-grade improvement, Cement Stabilization for base and Sub base, Geo-textile for sub grade improvement, Gravel with Slag, Terrazyme Compound, Waste Plastics, Nano Technology with Water proofing (Zydex) which are found cost effective.
Odisha has already constructed 954 kilometers roads with such technology. Moreover, an attempt has been made to convert a length of 945.78 kilometers of other roads from conventional technology to green technology which is found eco-friendly.
Further attempts are being made to use this green technology for construction of the roads within the forest area, causing minimal damage to flora and fauna.
As a pilot, roads have been built using Terrazyme, a non toxic soil stabilisation product that enhances road quality and reduces maintenance costs, in two districts in Odisha.
Use of Water Bound Macadam (WBM) methods has reduced the cost of road construction by 70%. Instead of 390 cubic meters of metal, only 97 cubic meters of metal was used.
Granular Sub Base (GSB) layer was eliminated and transportation of material was reduced by using local soil, thereby saving on fuel and emissions from vehicles.
Transportation of 405 cubic meters of GSB material was avoided by using Terrazyme. Another advantage of using Terrazyme compound is that this material can be used during monsoon season. It also reduces time of completion of the road from 12 months to 9 months.
The use of the technology has been further extended to 3 to 4 districts. The savings per kilometer of road constructed using Terrazyme is approximately Rupees 1.5 Lakhs.
These roads perform like all weather roads even when the road is left without blacktopping. It is revealed that no damage to road in the shape of potholes and rutting is caused during monsoon.
The cold emulsion bitumen is another substitute for currently prevailing hot bitumen which is presently used in construction of roads. The cold emulsions are used in forest areas to protect flora and fauna. During rains, blacktopping can be done using this material.
In some parts of the state where sub-grade strength is low making it unsuitable for providing stable foundation, by using 3 to 5% cement in sub-grade and sub-base, the pavement strength is increased considerably, thereby reducing pavement crust thickness. As a result, the pavement cost is reduced.
Use Nano technology like use of zydex and envirotac products
Likewise, the state is using Nano technology like zydex and envirotac materials in sub grade as well as sub-base layer in area vulnerable to floods and inundation. This provides water repellant abilities thereby reducing seepage.
Odisha has been using cell filled concrete pavement in place of conventional cement concrete pavement in rural areas which has not only reduced the cost of pavement but also reduced time of completion.
Further, another new technology like use of Geo-textile in rural roads is found reliable and suitable in flood prone area causing minimum erosion to the pavement even after inundation of the road by the flood water for a prolonged period.
Use of green technologies in road construction, Odisha wayAs a part of eradication of waste plastic in urban area, the said material is used in hot bitumen as a blending material for construction of all weather roads which is found beneficial in curbing the environmental pollution.
Besides coldmix technology is found beneficial in forest areas. It reduces pollution and can be used in any season. Moreover, such road can be opened to traffic immediately.
Odisha being a coastal State is vulnerable to natural calamities like cyclones, floods, heavy rainfall every year in which working period for execution of road project is very limited.
Cold mix technology
By adopting cold mix technology, the road execution work can be expedited in rainy season thereby extending working period and such road can be opened immediately for traffic. State has completed 810 Km length using this technology.
Normally, inside villages there is continuous flow of motorized traffic and pedestrians. There is also movement of cattle. These give very less time for curing after completion of cement concrete pavement and before opening to traffic. It results in poor road strength. Using cell filled concrete and roller compacted concrete pavement, this problem has been avoided.
Now State has proposed to complete several kilometers of road by using cell filled concrete. The roads with longer length need higher quantity of construction materials such as stone products, morrum and bitumen. These do irreparable damage to the environment. It also results in high transportation cost.
Use of new technology such as Terrazyme reduces the construction cost, pollution and save natural recourses. The Left Wing Extremism (LWE) problem affects many districts where providing good all weather road is quite challenging due to mountainous terrain and topography. Availability of resourceful contractors and their machineries is a problem in these areas.
Use of green technologies in road construction, Odisha wayThe state is using low cost cement stabilized pavements which results in higher strength. Rural connectivity is considered the best way of poverty alleviation. In view of faster rate of depletion of construction materials due to rampant mining, it has become imperative to use alternative materials in construction of low volume rural roads.
After completion of the roads, it is seen that a number of industrial units along with related infrastructure are getting established in the vicinity. Rapid industrialization of area has also occurred. The living standard of inhabitants has been enhanced by way of construction of better houses and dwelling units.
Connectivity has helped the government functionaries such as health workers, teachers and agricultural extension workers who now willingly move to the villages to offer their services. This ultimately contributes to prosperity and sustainable development of the area.
In areas prone to cyclone and flood, the use of Geo-textiles, Nano technology in embankments for construction of the roads has proved beneficial.
The roads constructed by using such technology are least damaged even after submergence of road by the flood water lasting for 2 to 3 days. In the approach roads to the bridges which get over topped by flood water such technology have been used and proved suitable.
This article first appeared in Big Wire