Construction in India. Image courtesy Aakrity Madhan.
Aakrity Madhan, a Masters of Design Studies candidate in the Harvard Graduate School of Design, received an LMSAI student grant to carry out an in-country study of India’s construction and demolition waste. Her project, “Circularity in Construction and Demolition Waste Management,” explored the life-cycle of waste, and offered some suggestions to lesson its climate impact. She shares her findings in the reflection below.
The Anthropocene or human-induced climate change, no more invisible to the naked eye, has had us witness a cascade of weather and climate extremes in every region of the global world. Daniel Pavlinovic in his article for UN News references the WMO report, Atlas of Mortality and Economic Losses from Weather, Climate and Water Extremes, to understand the social and economic implications of this phenomena. In the last 50 years, from 1970 to 2019, “There were more than 11,000 reported disasters attributed to these hazards globally, with just over two million deaths and $3.64 trillion in losses. More than 91 per cent of the deaths occurred in developing countries.” Better technology and warning systems might increase our resiliency against some of these disasters, however, global greenhouse gas emissions continue to be on the rise. The IPCC’s (Intergovernmental Panel on Climate Change) working report 2021, prepared by 234 scientists across 66 countries, warns that unless individual nation efforts to reduce carbon and other GHG emissions are reinforced, the internationally-agreed threshold of 1.5C global warming above pre-industrial levels is less than 20 years away!
One may argue that the onus of reversing climate change lies with the developed nations of the Global North owing to the disproportionately large negative impact of their consumption based economies. However, the effects of climate change will be felt the most in the underdeveloped and developing nations of the Global South. Couple that with evidence of increase in carbon emissions with economic growth in countries being lifted from extreme poverty, it becomes urgent to put in place forward-looking climate action plans for the all nations.
Role of the built environment in climate change
Buildings generate 40% of the annual global CO2 emissions, out of which building operations like heating, cooling, etc. are responsible for 28% emissions and embodied energy, the energy stored in materials from manufacturing to construction, is responsible for 11% emissions. While reduction in operational emissions can be achieved by shifting to renewable sources and increasing energy efficiency, the embodied emissions of buildings get locked in as soon as they are built. Architecture 2030, an advocacy group for carbon-neutral buildings, states that embodied carbon will be responsible for almost half of new construction emissions between now and 2050. It thus, becomes imperative to reassess how we build and even more to reassess how we demolish.
Architecture 2030, an advocacy group for carbon-neutral buildings, states that embodied carbon will be responsible for almost half of new construction emissions between now and 2050. It thus, becomes imperative to reassess how we build and even more to reassess how we demolish.
Scope of study
This is where studying current construction waste streams in developing nations like India becomes relevant. While construction and demolition materials constitute a significant waste stream worldwide, only 5% of India’s 10 – 14.7 million tonnes of annual C&D waste is processed. The rest is diverted to mismanaged landfills like the 65m high Ghazipur garbage mound in Delhi. The undue stress on natural resources from demand for virgin materials coupled with indiscriminatory dumping of C&D waste has many associated costs on public health and the environment – loss of forests, minerals, wildlife, increase in health risks, accumulation of toxic pollutants in and around dumping sites, and more. Using low embodied energy materials will reduce carbon footprint, however, moving the industry to a circular economy – reduce, reuse and recycle, will yield even better results.
A circular economy presents a framework and approach that aims to rethink the traditional linear production and consumption model (“take-make-dispose”) towards a system that explicitly encourages the closing of material and resource loops. Keeping this concept in mind, I studied the urban construction and demolition waste flows across Bangalore, Delhi, and Mumbai this past summer, a study enabled by LMSAI and Harvard GSD. As part of my study, I investigated government policies and implementation strategies, undertook visits to demolition sites and C&D waste recycling facilities, and studied the economic viability of resource recovery and recycling by understanding material flows through multiple supply chains. As the material makeup of Indian buildings has shifted towards concrete, fired bricks, and aluminium/ steel, there has also been a shift in focus on recycling over resource recovery. However, the dearth of collection and recycling infrastructure, poor accountability framework, absence of financial incentives, and lack of energy data in the public eye – contribute to a lukewarm response by the environmentally unaware construction industry to a seemingly intractable problem.
Challenges at various stages
Just how much waste is generated in India is a subject of mystery. Official records remain inconsistent when quantifying waste, with different ministries pegging the numbers in the range of 15 MT to 530 MT of waste per annum. The government often relies on outdated TIFAC (Technology Information, Forecasting and Assessment Council) estimation guidelines, which fall short in understanding both the quantity as well as composition of C&D waste. This presents a grave challenge in the planning and setting up of any end-of-life infrastructure. However, the recent Construction and Demolition Waste Management Rules and Regulations (hereafter referred to as Rules) were set up in 2016 under the umbrella of Swacch Bharat Mission (Clean India Mission). The Rules create a legal framework for handling and management of C&D waste, mandating different stakeholders to carry out their duties in the entire management roster from generation, transportation, storage, disposal, recycling to policy initiatives incentivising the endeavour.
The Rules mandate generators to segregate, store, and dispose waste in a reliable manner, submit a waste management as part of the construction approval process, and take on liability of noncompliance in the form of fines. However, ignorance and economics drive the magnitude of noncompliance issues. Small generators, partaking in home renovations or additions, remain unaware of disposal methods and sites, and small quantities of concrete and bricks end up on the side of roads and eventually, choke the sanitation sewage lines. Bulk generators, however, often contract demolition and eventual transportation of waste to sub-contractors that work on tight profit margins. Internationally, C&D waste is often classified as i) not easily recycled or disposed like paint, asbestos, and plaster; ii) recycled in industries other than construction such as timber, glass, paper, plastic; iii) easily reused and recycled in construction including soil, bricks, concrete, tiles, etc.
My conversations with various demolition contractors cemented the idea that the shift from resource recovery to demolition in the last 20 years is driven by profit margins. In the past, manual and painstaking demolition methods would be employed to recover many materials for resale, including bricks. However, the cheap and abundant availability of natural resources has limited this process to materials which can be salvaged for their economic value. Steel, electric wiring, doors, and windows are taken apart with care for sale to recyclers, and scrap dealers. Dynamic breakers and crushers are used to demolish the masonry and structure, finishing the job earlier than what would have been possible by manual demolition. The entire process is wired to be time and labour efficient. Materials – not so much.
The responsibility of transporting this material lies with the generators. Small generators are expected to bring the materials to designated collection points and bulk generators are expected to bring the waste to disposal or processing facilities, both at their own expense. In addition, the generators are charged for the processing of the waste. A study of the tipping and processing fees, and faraway dumping locations across the three cities sheds light on the inevitability of illegal dumping. Usually carried out by informal transport contractors running on shrinking profit margins, this is not an economically viable exercise. Further, ULBs (Urban Local Bodies) often lack financial resources to ensure last mile connectivity from collection points to processing facilities and are often reluctant to pay the tipping fees to recycling facilities. A mix of concrete, masonry, and broken plastic waste, then reaches one of three fates: illegally dumped in empty city plots, roadside or worse, wetlands; maliciously used for encroachment and reclamation of environmentally sensitive land; or rarely, dumped in government designated landfills or recycling facilities. End of life scenarios Dumping Ground/ Landfills: The landfills like Shastri Park in Delhi or the Deonar dumping ground in Mumbai receive solid, medical, wet, and C&D waste, all dumped indiscriminately. This leaves very little scope for material recovery because of high incidence of contamination. The segregation and cleaning alone would be a costly affair, making the exercise an unfavourable undertaking. However, ragpickers which form the informal underbelly of the construction industry still manage to salvage textiles, plastics, and steel for recycling.
The Rules largely ignore the involvement of these stakeholders. Nevertheless, landfills help with an important exercise – estimation of waste. Albeit, certain interventions need to be made to account for waste that lies on scattered around the city, each landfill performs the important role of keeping an account of the waste that is brought in. The three cities, set in politically and geographically different contexts, have each had varying levels of success in dealing with C&D waste, especially evident from the different tiers of recycling infrastructure setup – Delhi, being the political centre of India was the first to set up a recycling initiative and has scaled to over 4 decentralised plants to cater to different parts of the city; Bangalore, away from the political landscape of Delhi, with ample land in the outskirts, has facilitated two recycling plants but with weak implementation; on the other hand, Mumbai, the financial capital of the country with a land scarcity issue, boasts of zero recycling facilities for C&D waste.
All of the existing and upcoming recycling plants are operated under Public Private Partnerships, to leverage the expertise of the private sector to solve for this civic problem. At the recycling facilities, the waste undergoes sorting, cleaning, crushing, and processing into products for sale. Most facilities process the waste into building aggregates of various sizes based on demand, used for non-structural applications like backfilling and levelling of roads. Sand is manufactured in the highest quantity owing to the existing ecological stress on and subsequent high cost of river sand. Also based on demand and further incentivized by buy back policies of the government, the recycling plants across Delhi manufacture paver and structural concrete blocks using the aggregates obtained from the waste. Despite being certified fit for structural applications, the cement blocks face many policy and perception roadblocks.
The Rules mandate the use of 10-20% recycled material in government infrastructure projects but do not specify the application. No such requirement is made of private projects. To add to this, the Goods and Services Tax (GST) levied on recycled materials is 18% as opposed to the 5% levied on virgin materials. The aspirational desire to use new materials and lack of trust in recycled materials furthers the slow uptake of these materials.
Concrete, bricks, and rubble – all inert waste do not seem to pose an immediate threat unlike municipal solid waste to a nation which still grapples with toxic waste strewn about roads, problems of manual scavenging, and polluted water bodies. However, it is now important to stay ahead of the issue before it silently depletes pristine and ecologically sensitive natural resources and makes the problem critical. First-hand investigation of the C&D waste management industry has left me with an optimism that many small interventions can help solve this seemingly intractable problem. The Rules are a good first step in establishing good practices for all stakeholders but much more needs to be done.
Awareness: The efforts start with awareness. Early-stage, easy-to-use design tools for architects and builders could be helpful in limiting emission impact and optimizing construction for resource recovery. It also becomes important for the government to increase visibility of recycled products in use in government structures. The Supreme Court building in Delhi is one such example. Citizen awareness is a critical next step. Similar to the initiatives around municipal solid waste, circular economy awareness drives and citizen groups should be initiated. The same needs to be done for state government officials, who often decide on design and implementation of guidelines. Here, however, the initiative needs to go beyond awareness and move into developing a good business case for the exercise.
Business case: Financial infeasibility qualifies many of the waste management guidelines from being implemented throughout the supply chain. Most ULBs struggle to execute The Rules and implementation strategies designed by state governments because the small market of recyclables coupled with high cost of land needed to build this infrastructure makes this exercise a financial liability for them. A stronger prosecution of defaulters in the form of fines could be used to relieve some of the financial ‘burden’. Recycled materials need to be made financially attractive to the public. Additionally, the Rules currently compete with the informal sector that forms the backbone of the C&D recovery, reuse, and recycling industry. The existing informal infrastructure could be leveraged to increase resource recovery efficiency and generate livelihoods. It becomes important for the ULBs to consider the long-term financial benefits of investing in these short-term waste management measures.
Technology Integration: Currently, there exists a dearth of capacity and expertise in this sector. While the government is on the right path with public private partnerships, these efforts need to be democratized to bring in individual experts rather than big entities that can afford to work with dipping profit margins. The Malba Project, by Shamita Chaudhary is one such effort to map and clear out C&D waste hotspots across the country with the use of crowd sourced information. Similar technological interventions could be made to correctly estimate quantities of waste by using AI and GIS technologies. IITs and other public educational institutions of good research repute should be invited to fill the informational gaps around environmental data and ramifications of indiscriminate waste spread in the cities. Further, one could also examine new ways of building that allow for easy recovery. Imagine mortarless stacked brick construction!
I am grateful for the support of the Mittal Institute, Harvard GSD, and my mentor, Matan Mayer, who have enabled this study. This two-month on-ground study has paved the way for many research opportunities and collaborations. I am now considering the possibility of centering sustainability literacy as part of my research work, an avenue that I haven’t explored yet. This could translate into a workshop, a game, an early-stage design tool, or even a podcast – the possibilities are endless! Design is intrinsically optimistic. It is this optimism that leads me to believe that I can shoulder the onus of leaving this planet a better place than I inherited. Buildings generate roughly 40% of the annual global CO2 emissions, with building operations (heating, cooling, etc) comprising 28% of that, and embodied carbon – the energy stored in materials from manufacturing to construction – responsible for 11% emissions. Architecture 2030, an advocacy group for carbon-neutral buildings, states that embodied carbon will be responsible for almost half of new construction emissions between now and 2050. It becomes imperative toreassess how we build, and even more imperative to reassess how we demolish.
Construction in India. Images courtesy Aakrity Madhan.