Who cares about construction waste in Bengaluru?

Bengaluru: According to official estimates, Bengaluru produces 2,500-3,000 tonnes of construction waste daily. This includes cement and concrete waste from buildings and roads, mud, wood, ceramic items, tiles and other materials.

The Construction and Demolition (C&D) Waste Management Rules (2016) say that the onus of disposing of construction debris lies with the person or entities generating the waste. The municipal body, Bruhat Bengaluru Mahanagara Palike (BBMP), is responsible for implementing these rules in Bengaluru.

Seven years later, despite interventions and suggestions by a committee monitored by the National Green Tribunal and efforts by NGOs to set the issue right, construction debris is seen lying everywhere in Bengaluru. Mud and concrete waste get dumped on roadside footpaths, lakes, and catchment areas, sometimes causing floods on roads and low-lying areas.

Demolition activities are largely unorganised

Currently, there is no rule or license to be complied with for the demolition of buildings. People surrender electricity and water connections and go ahead with demolition after getting a new plan approved by the BBMP. Even demolition contractors do not need special expertise. Even those who do the masonry work take up demolition works, wherein they reuse as many items as possible, say sources.

Many of the individual buildings demolished now are old, built using bricks and mortar. Therefore, mud forms a large part of the waste. A building demolition contractor, preferring anonymity, told DH that mud is the most problematic element as it cannot be sent to any recycling unit and must be used to fill lands. Though it is non-polluting, he said the lack of designated sites to dump mud is a problem.

The individual buildings being demolished also have tiles and cement. Undamaged usable tiles, blocks and bricks are taken away by those who want to use them and reduce the cost of construction. Even wooden doors and items are taken away. But whatever is damaged gets mixed into the mud waste and goes to landfill. While ceramic toilet commodes can go to the crushers in the C&D recycling plants, their extraction is often not separate; therefore, they do not get recycled, says a demolition contractor.

In the case of concrete buildings, demolition contractors extract steel from the buildings and collect concrete waste and wood separately. This works out more economically for demolition contractors as the recycling value of the waste is higher.

“Over time, the usage of red bricks is decreasing, so 20 years from now, the building waste will involve only concrete, which has higher recycling value,” says Roopesh Kumar, a developer from HSR Layout in Bengaluru.

Recycling status

The city has one C&D recycler authorised by the KSPCB—Rock Crystals, which can process more than 5 lakh tonnes per annum today. At the end of the financial year 202-23, with a capacity to crush 3 lakh tonnes yearly, it could process only 48,000 tonnes. Amid the lack of aggregation centres, the plants are receiving construction waste from the nearby 10 km surroundings, but this arrangement is not working for the rest of the city.

Some developers have their own recycling units to process concrete debris produced by their projects. They also pay retail C&D waste transporters to send it to their facility.

“The government should enforce the law strictly so that people are discouraged from dumping at unauthorised locations. Heavy penalties should be imposed,” says the spokesperson of a prominent real estate firm.

Roopesh Kumar, an entrepreneur living in HSR Layout, has experimented with collecting construction and demolition debris in the past and supplying it to big builders to process and use for backfilling of their projects, etc. He says he got up to Rs 100/tonne for the waste he supplied to big developers.

He is dabbling with a system to collect C&D waste in four areas in south Bengaluru. Retail demolition contractors who handle non-bulk demolitions transport waste into the collection centres he owns. He segregates the debris into mud blocks, concrete and other categories. Rag pickers come and collect what they want from the waste. People looking to build low-cost houses collect all usable items from the debris.

However, the magnitude of the city’s concrete debris has made him think creatively. He plans to construct a recycling plant and make recycled blocks, interlock tiles and other products.

“Even if there are ten more plants like in the city, there is not going to be a shortage of C&D waste,” he says. He also plans to make fuel briquettes out of unusable wood from the construction debris.

“Just 1 per cent of the C&D waste is being processed currently. The biggest hurdle to this is the cost of transportation,” he says. It does not work out for retail demolition contractors to send the waste to a plant lying around outside the city, which leads to violations.

If there is an aggregation centre in every ward, or atleast one for a few wards, it becomes a viable solution, Roopesh feels. It can reduce traffic congestion, time and fuel consumption while generating value for the transporters. Hence, compliance with rules and regulations will improve, and more concrete debris will be recycled, he says.

Using the recycled products

Is there a market for recycled products? The opinion is divided across the spectrum. Roopesh, a developer himself, says there is a good market for recycled blocks, backfilling materials, curbstones and footpath tiles.

Yogananda M R, Mrinmayee Consultants, a firm engaged in research and development of alternative technologies, talks about mud concrete, where mud is used in addition to concrete as a raw material. 

“A mix of soil, fine aggregate, coarse aggregate, cement and lime gives stabilised mud concrete. This can be used in new constructions and all load-bearing structures that do not need reinforced beams and columns. This something we are working on,” he says. He says there is a lot of potential for such reuse, which reduces the stress on nature.

Rajesh Korah, a partner at Rock Crystals, says there needs to be awareness about using recycled materials. Government bodies like BMRCL, BWSSB, and KRIDE do not use stipulated amounts of recycled materials in their construction work. “Big firms engaged in infrastructure works with the best minds from IIT and IIM in the team do not know how to comply with C&D waste management rules and recycling,” he says.

The BBMP has started enforcing the 2015 C&D management rules, where the bulk waste generator (producing more than 20 tonnes per day/ more than 300 tonnes) has to provide a waste management plan approved by the BBMP. This involves calculating how much waste will be produced, how it will be managed or recycled and how much recycled material will be used.

However, the BBMP and pollution control authorities cannot continuously monitor all the vehicles and builders. Government bodies such as BMRCL and KRIDE do not send their waste to authorised recyclers. Many huge construction works that go on inside SEZs disappear unnoticed. Thus, though there is a system, large builders are not complying with it, sources added.

The rules say KSPCB should grant authorisation to the C&D waste processing facility, monitor the implementation of the rules by the local bodies, and submit annual reports to the Central Pollution Control Board and the state government. However, sources in KSPCB say monitoring is complex for the regional officers as there is no mechanism to inform them of where and when work will occur and the approved plan for managing the waste.

New C&D tender soon

Harish Kumar, Chief Executive Officer of Bengaluru Solid Waste Management Limited, says that the tender floated for the overall management of C&D waste in Bengaluru was referred to the committee headed by Justice Rathnakala as the amount exceeded Rs 50 crore. Since it involves the public-private partnership (PPP) model, it will be presented before the PPP Cell in the Infrastructure Development under the chief secretary.

Once the cell approves the tender, it will be floated again. The tender is comprehensive and has a plan for C&D waste aggregation centres. Officials say that individual demolition contractors will not be affected as they can supply to aggregation centres.

An NGT committee headed by Justice Subhash Adi has made many recommendations to the BBMP, including embedding the waste management plan into the plan approval process itself, registering all C&D transport vehicles in the city so that no unauthorised dumping takes place, and coming up with an app to manage the C&D transportation. How much of this will be incorporated into BBMP’s functioning is uncertain.

Circular Realty

Circular Realty is a project by Saahas, an NGO on waste management, funded by Tata Realty groups. The project aims to design a way to manage C&D waste for non-bulk users who produce less than 20 tonnes per day and are not regulated by any rules. Call them on 85100 91213 if you want to dispose of C&D waste responsibly and do not have a way to do it.

Concrete debris dumped beside a road in Koramangala. Such scenes are common across Bengaluru as the city lacks aggregation centres for C&D waste.