Existing Regulatory framework for C&D waste
Construction and demolition (C&D) waste is probably the oldest kind of solid waste known to humankind, but regulation of its management is a recent development. Although waste has always been generated in the construction, but most of countries didn’t formally record it as waste and track its generation until the end of 20th century [14]. The developed world has made great advancement in managing and recycling C&D waste in the last two decades as they have formulated policies targeting waste [9]. India, however, lags severely in this sector as C&D waste management has remained finite in scope and economically non-viable because of policy scramble.
International Standards
European Union (EU): Modern utilisation of C&D waste goes back to history in Second World War for rebuilding cities, when the massive requirement of aggregate was fulfilled by processing of C&D waste. But actual policy to manage C&D waste only started after 1975. Multiple legislations were taken in place that made the development of waste management plans an administrative requirement and led to the establishment of an EU waste catalogue [15].
In 2004, the EU notified new standards for aggregates from ‘natural, recycled and manufactured materials’, which focuses on the robustness and did not discriminate between natural and unnatural sources [16]. In 2008, the Waste Framework Directive (WFD) was issued, which requisite that 70 percent of the C&D waste by weight within the EU was to be recycled by 2020 [17]. The WFD target has been met at the EU level but not individually by all the member states. Sweden, Denmark, Switzerland, Austria and France are being managed to recycle as much as 90 percent of their C&D waste.
United States: United States started formalizing management of C&D waste around the same time as Europe. The Resource Conservation and Recovery Act (RCRA, 1970) called for utilization of recycled construction materials in federal procurements. This resulted in federally funded projects consolidating the requirements for usage of recycled building materials. RCRA was amended in 1976 and recognized the national importance for recycling waste and development of specifications for secondary materials and their incorporation into building construction standards [18]. But a comprehensive national assessment of C&D waste was not done till the 1990s. USA reported 70 percent of recycling rate in 2019 although the RCRA requirement is still not mandatory [9].
Indian Legislation, Rules and Acts
In India the first organized effort to recycle C&D waste was in 1999. A decentralized solution for C&D waste management was developed and promoted by the Youth for Unity and Voluntary Action (YUVA) in Navi Mumbai together with City and Industrial Development Corporation (CIDCO). The collaboration led to recycling of C&D waste over 1,500 tonnes in 2002–06 [19]. However, in 2009, CIDCO - YUVA Building Centre was forced to shut down C&D waste recycling plant as there were no policy or market support to sustain its operation.
On the policy front, the first thorough mention of C&D waste came in the manual on Municipal Solid Waste Management in 2000. This manual of Union Ministry of Urban Development (MoUD), Government of India (GoI) includes a chapter on C&D waste. The manual gives basic non-obligatory guidelines on handling of C&D waste [20]. Meanwhile, in 2012, the Union Ministry of Urban Development (MoUD) suggested that all states should set up environment friendly C&D waste recycling facilities in all cities and towns with population more than 1 million [21]. But, nothing much though happen in the ground reality. In 2015, BIS added an 11th chapter to the National Building Code 2005 titled ‘Approach to sustainability’ which recognised that recycled C&D waste as building material and suggested possible use of it [22]. To build confidence in the performance of recycled C&D waste products, quality certifications were introduced in 2017. Later, the Green Rating for Integrated Habitat Assessment (GRIHA) Product Catalogue added recycled C&D waste products as green and made them eligible for rating points under GRIHA’s green-building rating system [23].
In 2016, the Ministry of Environment, Forest and Climate Change (MoEFCC), GoI notified the ‘Construction and Demolition Waste Management Rules’. This was a significant step forward and addressed most of the significant issues around C&D waste management in the country. This created the much needed legal framework for reuse and recycle of C&D waste in the construction industry. They also provided a timeframe for establishing and implementation of the rules [2].
Table 1
Timeframe for planning and implementation of C&D Waste Management Rules, 2016 [2]
Compliance criteria | Cities with population of < 0.5 million | Cities with population of 0.5–1 million | Cities with population of > = 1 million |
Policy formulation by state government | 1 year | 1 year | 1 year |
Site identification for collection and processing facility | 1.5 year | 1.5 year | 1.5 year |
Commissioning and implementation of the facility | 3 years | 2 years | 1.5 years |
Monitoring by SPCBs | Twice a year, i.e., once in six months | Twice a year, i.e., once in six months | Thrice a year, i.e., once in four months |
In ‘Swacch Survekshan’, a new indicator for C&D waste management was introduced with the aim of rewarding ULBs that have a procedure in place to manage C&D waste as per the C&D Waste Management Rules 2016. The C&D indicator carried 50 points of the total 5,000 points available in 2019 [24]. In 2021 Swachh Survekshan, has recognized non-structural applications of C&D waste that don’t require the specialised processing recycling plant as legitimate reuse, eligible for gaining ranking points. This is the first instance that the reuse of unprocessed waste has been recognise as acceptable utilisation of C&D waste in official documents on C&D waste. This is noteworthy as it opens the door to involve the informal sector in the formal management of C&D waste [25].
Current Scenario and Composition of C&D Waste
Technology Information, Forecasting and Assessment Council (TIFAC), Department of Science and Technology, GoI, estimates that demand for construction material in India for 2021–22 will be 380 MT for cement, 50 MT for steel, 600 billion bricks, 400 million cubic metres (cu.m.) for aggregates and 40 million cu. m. for timber [21]. Without an alternative to these construction materials and in the wake of emerging material crisis, much of demand is bear by virgin materials with huge environmental cost. Sand, soil, stone and limestone are critical natural resources used in the construction sectors that are already facing massive supply disruptions and price hike due to mining bans and restrictions [26]. This has pushed the policy makers towards finding the sustainable alternative materials and substitutes. Construction researchers are now looking at a wide range of viable options that include industrial waste, natural alternatives and reuse of C&D waste. It has now been established across the world that the recycling and reusing C&D waste is a viable alternative to naturally sourced construction material [27]. Most developed countries have already taken advantage of this and are converting it into resource with varying rate of success.
International Scenario
The earliest known usage of recycled C&D waste dates back to days soon after the Second World War, It was then, that large quantities of aggregate required for rebuilding the cities, was not available and recycled aggregate obtained from the debris of demolition was used up to the extent of 20 to 50% in concrete, blocks, pavers, etc. [28]. It is difficult to give exact figures of C&D waste produced in a typical construction site, yet estimates from various research works conducted globally, state that 4–30 percent of the total weight of building materials delivered to a building site becomes waste due to damage, loss, and over-ordering [29]. The composition and quantity of C&D waste may vary according to the type of structure and the scale of construction, demolition, or renovation activities. The streams and composition of on-site wastes are highly variable, depending on the region and the construction techniques used, Overall, C&D waste can be broadly classified into three categories: waste which is: (1) not recycle and have disposal issues like plaster, asbestos, chemicals; (2) not recycle in construction industry but can be recycle elsewhere like timber, plastic, paper; and (3) potentially valuable and can be recycle or reusable like inert waste such as concrete, bricks, stone masonry, tiles and asphalt. In terms of waste streams and weight, the brick masonry and concrete have the largest potential for recycling in the construction industry [30]. The findings of this study are based on comprehensive research studies conducted across the US, the UK, Spain, China, Brazil, Korea, and Hong Kong, which compared the streams and volumes of construction waste in these countries.
The study of the C&D waste management scenario reveals that it has been driven by “constraints” in countries abroad. The C&D waste reuse and recycling rate, in the EU and USA, have reached 79 percent and 70 percent respectively [31]. Some members of the European Union and smaller nations like Singapore have reported over 90 percent recycling and reuse rate [32]. Tokyo enforced the construction waste recycling law in which all construction projects must have a recycling program for C&D waste. A simplified form indicates how the recyclable and fine materials will be dealt with and they track the reuse/ recycling of C&D waste. The current rate of recycling C&D waste in Tokyo is more than 99% [33]. In the years 2018-19 Australia generated 27 million tonnes of C&D waste out of which 20.2 million tonnes of C&D waste is recycled and reused which accounts for a 74.8% rate of recycling C&D waste [34]. In Australia, the Nalawala Hall has the world’s first concrete load-bearing foundation slab in which 95% recycled aggregates have been used [34]. Despite encouraging evidences of reuse of C&D Waste, putting C&D waste in landfills has been the cheapest and most convenient practice in most countries across the globe. In all such places continuous and indiscriminate dumping results in operative landfills getting exhausted and many a times land not being available to create new landfill areas. Reports and studies related to all such cases or other reasons like increasing cost of landfills sites, strict environmental rules, public resistance to landfills, etc. have enforced local bodies / municipalities to adopt recycling and reuse of C&D waste. Also, globally, it is now a well-established fact that modifying the construction process and waste management policies can to a large extent prevent environmental degradation and pressures on land.
Table 2
Percentage of each waste category from the total generated in different countries.
Waste sub-stream | Australia | Canada | China | India | Netherland | Norway | Spain | United Kingdom | United States |
Soil and rocks | 6 | - | - | 35 | - | - | - | - | - |
a) Concrete | 21 | 23.9 | 8–35 | 30 | - | - | - | - | 70 |
b) Ceramic | 16 | 18.7 | 15–50 | 25 | - | - | - | - | 2 |
Mixed concrete and ceramic waste (a + b) | 37 | 42.6 | - | 55 | 64.02 | 67.24 | 85 | 33 | 72 |
Mixed waste | 5 | - | - | - | 4.87 | - | - | - | - |
Wood | 19 | 30.6 | 1–5 | 2 | 6.1 | 14.58 | 11.2 | 27 | 7 |
Paper | 10 | 4.3 | 5–20 | - | 0.22 | 3 | | 18 | - |
Plastic | 4 | 3 | - | - | 0.76 | - | 0.2 | - | - |
Gypsum | 8 | - | - | - | 1.42 | 2.77 | - | 10 | 3 |
Metals | 9 | 8.1 | 1–8 | 5 | 12.88 | 3.63 | 1.8 | 3 | 1 |
Asphalt | - | - | - | 2 | - | 0.38 | - | - | 14 |
Other | - | 1.8 | 10–20 | 1 | 9.35 | 9.44 | 1.8 | 11 | - |
Source | [35] | [36] | [37] | [21] | [38] | [39] | [40] | [41] | [42] |
Indian Scenario
India’s urban population increased from 286 million in 2001 to 377 million in 2011 and it is projected to go over 800 million by 2050 [43]. India’s urban built environment has also been growing rapidly in past few years, and can rightly be expected to continue to do so for the upcoming years first to accommodate the growing urban population and second for aspirations of higher living standards [44]. Many cities under several urban development programs have already undertaken infrastructure development works, construction of new buildings and redevelopment activities [45]. Each of these development or redevelopment activities produce construction and demolition waste (C&D waste) which in all likelihood has its management issues and environmental implications. Currently, landfilling and open dumping along roadsides and in water bodies are the dominant C&D waste management practices [46], none of them being sustainable. On the contrary, recycling and reuse of C&D waste will offer opportunity to save landfill space, reduce consumption of virgin materials, reduce the environmental footprint of cities and help them in being sustainable.
In India, there are very few studies on characterization of C&D waste. The C&D waste characterization study done by TIFAC in 2001 highlighted soil, sand and gravel (fines); brick and masonry; and concrete accounts for 90 per cent of the waste [47]. Similar studies and surveys carried out by other governing bodies in Delhi and India found that the bulky materials jointly make more than 90 per cent of the C&D waste (see FIGURE 2). The remaining 10 percent of C&D waste comprises wood, metal, bitumen, plastics, etc.
In most of the Urban Local Bodies (ULBs) where proper management of C&D waste is not established, it mixes with municipal solid waste which results in increased processing cost and reduced efficiency. A study by Centre for Science and Environment (CSE), New Delhi (India) shows that as many as 53 metropolitan cities were expected to set up recycling facilities to recover and recycle material from C&D waste by 2017 as per C&D waste management rules, 2016. However, only 13 cities could do so by 2020 [48]. There is not much gap between generation of C&D waste and the cities in which recycling plant is being established except Delhi and Hyderabad (FIGURE 3) This is inadmissible when the demand for primary construction material, including minerals, stone, sand, and timber, is growing at an unprecedented rate. Some advanced technologies are available in India, and are already being used in cities such as Delhi and Ahmedabad. Many initiatives had been taken even before the notification of the C&D Waste Management Rules in 2016. A recycling facility plant operates through a combination of processes that can transform the C&D waste into aggregates, sand, silt, and clay, all of which can be reabsorbed and reused as construction material [49]. Additionally, many value-added products such as concrete blocks, kerbstone and paver blocks made up of recycled C&D waste are excellent substitutes for conventional products.
Challenges in C&D waste management
Large scale construction projects for housing, industry & infrastructure development are under implementation across the globe. Development of economic zones, industrial corridors, redevelopment & rehabilitation works, besides repairs & renovation contributes to the large magnitude of C&D waste generated every day. Suitable laws are being framed by the local authorities. However, limitations in the enforcement of such laws have been reported [13]. Quite often C&D waste from individual households finds its way into nearby waste bins making the municipal waste heavy and degrading its quality for treatments such as composting or energy recovery. On the other hand, common practices of private contractors include dumping it in an unauthorized manner along roads or other public areas or in privately owned lands and low-lying areas for a price. The major challenges which are faced to successfully recycle and reuse of C&D waste. It is important to understand the challenges so that objective of managing and reuse of C&D waste can be met and upscaled too.
Challenge in Implementing Policy/ Regulation
Despite the notification of C&D waste management under the ‘Waste Rules, 2016’ and other relevant standards, these haven’t been implemented yet in most of the cites including megacities. As an example, Mumbai is the richest urban local body, but it is still waiting to have an operational C&D waste recycling plant despite of numerous pressures from Bombay High court. It is important that enforcement of rules and execution of recycling units is taken on priority by local governments.
Challenge of Collection and Transportation of C&D Waste
There is a substantial dissimilarity between ULB’s in term of waste transportation practice. C&D waste is transported to disposal site or collection point by contractor or house owner with a minimal fee to transporters. Some ULB’s even have ‘on call- pick up service’. In case of Delhi, the responsibility of transporting the waste is of waste generator with their own expenses and then ULB take it to the disposal site. As reported, most of the private and informal transporters here are not aware of the collection point and sometimes they are asked to pay extra charges for dumping at the designated location [48]. As transporters work with minimum profit, this adds to their cost and often the result is littering of waste on the roadside.
Challenge of Involving State Government Agencies/Departments
State government departments are required to frame policies that support the C&D waste management under the ‘Waste Rules, 2016’ to help in implementation taking local context. In most cases, there engagement is poor. There was some interest generated from the states, after it was found that C&D waste is a major sector for air pollution control intervention under the National Clean Air Programme (NCAP) [50]. Moreover, the active involvement of State agencies is also needed for financial assistance and also in supporting the cities in their struggle to find appropriate land for C&D waste processing facility. The latter is also related to restrictions by outdated zoning guidelines and ‘not in my backyard’ sentiment among citizens.
Challenge of Pricing of Recycled C&D Waste Products
Trust in quality of recycled waste is mandatory for putting it in use in construction projects. Central for Public Work Department (CPWD) has already adopted policy for usage of recycled product in its projects. Use of recycled product of C&D waste in new building of Supreme Court in Delhi [51] is a recent example of recent practices adopted by CPWD. For product promotion, pricing has always remained as another concern. The Ministry of Housing and Urban Affairs (MoHUA), Government of India (GoI) stated in public forum that pricing of recycled product should be less than conventional building material, but in reality, recycled C&D product are being taxed higher. Currently, conventional building material are taxed at 5 percent and recycled C&D product at 18 percent [52]. As a promotion strategy, products obtained from recycled material should be made tax free or be levied with lower tax than the products manufactured using new materials.
IntegratinG Circular Economy Concept in C&D Waste Management
The circular economy concept is gaining momentum worldwide among researchers of diverse fields [53]. Circular economy is primarily a closed cycle similar to our ecosystem where nothing goes waste as every residual material can be utilised for making a new product after removing the toxic constituents [54]. Introduction of circular economy concept in the construction sector creates opportunities for innovations in reducing residual and waste matter, cutting down on requirements for fresh raw materials and cost reduction throughout the lifecycle of structure and its various components without any compromise on their quality. Complete circularity in C&D waste management can be achieved only when a sustainable and comprehensive strategy and action plan is prepared and implemented throughout the lifecycle of construction projects [55]. From the life-cycle’s perspective, waste hierarchy and circular economy, both consider the whole life cycle of a product, including the pre-use phase, use phase, and post phase [56]. Circular economy (CE) can be promoted by material reuse either by direct use or by repair/refurbishment that ensures use of C&D Waste within the construction industry in all the three aforementioned phases of the lifecycle of construction projects. Different approaches for introducing circularity in C&D waste are being shown in TABLE 1.
Table 1
Approaches for introducing Circularity
Construction approach | Waste Management approach | Legislative approach |
Design and construct for recycling and Reuse | Preparing for reuse | Set ambitious targets |
Reducing use of virgin materials | Data collection through ICT based technology | Reduce GST on recycled materials |
Reduction in the overall waste generation by setting construction practices Standards | Decentralized cluster-based approach for recycling waste | Setting green building standards |
Integration of a demolition plan | Downcycling: the current main outlet | Mandate use of certain percentage of recycled waste with the new construction material |
Life of the structure specified | Restrict landfilling | Implement incentive measures |
Over time the waste hierarchy and circular economy have evolved to emphasize the design and use of a product before it turns into waste. Therefore, we can see that circular economy and waste hierarchy share a joint philosophy, aiming to manage waste by rethinking, redesigning, and repurposing in order to improve the resource effectiveness of a product and to reduce the generation and adverse impact of waste [57]. The minor difference is that the waste hierarchy still allows disposal, while the framework of a circular economy does not. The present models for sustainability assessment rarely include all three aspects of sustainability (economic, environmental, social). Also, almost all of the models are based on statistical records on C&D waste quantities which often underestimate the actual C&D waste generated. This paper proposes a conceptual model of efficient C&D waste management for circular economy. This will best require an approach involving economically, environmentally and socially sustainable C&D waste management strategies. A model including all three aspects of sustainability while integrating circular economy concept in C&D waste management is illustrated in FIGURE 4.
Conceptual model of efficient C&D waste management
With the increasing urbanisation a sizeable number of re-development, revitalisation and rehabilitation projects together with new works of housing and infrastructure have become a common sight primarily to meet the increasing demand. Large volume of C&D wastes is generated and in absence of stringent legal and institutional mechanisms, the haphazard dumping and non-utilisation of debris results in momentary air pollution, or dumping alongside roads, open drains, water bodies, vacant plots or mixing up with municipal solid waste. In Australia, Japan, United Kingdom, United States of America, EU nations and other developed countries, the best practices involving the 4R concept i.e., reduce, reuse, recycle, and recover are in place for C&D waste management. On the contrary, in the third world or developing countries like India, Middle-east and South-east Asian nations, the best practices to be applied are still being researched to maximise the rate of recycling and reuse of C&D waste in construction industry. India as a developing country now focuses on construction and demolition waste to reduce the harmful impact on environment.
The literature mentions several parameters which are deterrent while others which act as drivers for utilising C&D waste in an effective and efficient manner. The barriers include collection and transfer of waste, illegal dumping, illegal mining, lack of standardisation, awareness and public trust on recycled products, taxation on recycled products, etc. The critical drivers for successful implementation of C&D waste management are appropriate data reporting of generation of C&D waste, C&D waste management rules and its enforcement, focussed involvement of government and non-government agencies, promotion and standardisation of recycled products, etc., The reported motivators which can help in improvement of management of C&D waste include promoting use of recycled product, green building rating system, setup of C&D waste processing facility, and efficiently handling of C&D waste. The strategies that help in systematic construction waste management are building with eco-design, involvement of informal sector, on-site sorting and demolition practice, and finances of recycling and recovery cost.
A model has been reported as a process to provide appropriate characterisation and indicators which help in developing detailed description and coherent analysis of a research [58]. Using parameters obtained from literature on construction Industry, applicable legislative rules and regulation of C&D waste a conceptual model been developed considering the gaps or challenges faced in C&D waste management and to integrate circular economy. The proposed model is illustrated in FIGURE 5. This intends to investigate the current practices of waste management, barriers, motivators and factor influencing systematic construction waste and to assess the critical drivers, barriers and motivators for implementing good C&D waste practices in developing countries.
The green and red lines indicate positive and negative relationship respectively, with arrows indicating directionality of the component influencing the other. All these factors together show forward and backward linkages with each other and can be seen in FIGURE 5. A conscious approach to minimise and mitigate deterrent factors and integrating the drivers with motivators in an optimal manner will help to improve the current issues on C&D waste management and also result in efficient handling of construction waste.