Sustainable Strategies in a Megacity
Making Mumbai Liveable
Mumbai’s population is forecast to keep growing for at least the next twenty years. Without action, the housing shortage, polluted air, traffic gridlock and patchy water supply will get worse. The city authorities and central government are pursuing large, top-down projects. Communities and NGOs are running smaller, bottom-up schemes. Both approaches are needed if Mumbai is to become more sustainable.
Top-Down: City-Wide Strategies
Top-down strategies are led by Mumbai’s Municipal Corporation, the Maharashtra state government, and partly funded by the World Bank. They aim to fix problems on a city-wide scale, faster than community projects could.
Transport. The Mumbai Metro is being expanded from one line in 2014 to a planned 14 lines by 2030, with the goal of carrying 12 million passengers a day. The first elevated coastal road opened in 2024, cutting an hour-long drive into 20 minutes. Both projects aim to take pressure off the suburban rail network and the choked road system, reducing journey times and fuel use.
Water. The Middle Vaitarna Dam project boosts the city’s daily water supply by 455 million litres. The Brihanmumbai Municipal Corporation has rolled out smart water meters in pilot wards to detect the leaks that currently waste an estimated 30% of the supply.
Waste & Air. The Deonar landfill, which had been on fire intermittently for years, is finally being closed and converted into a methane-capture plant generating 12 MW of electricity. Mumbai has switched 1,800 BEST-fleet diesel buses to electric to cut roadside pollution. The 2022–27 Mumbai Climate Action Plan sets the city a target of net-zero emissions by 2050.
Housing. The Slum Rehabilitation Scheme rehouses slum dwellers in mid-rise apartment blocks built by private developers, who in return get the right to build profitable luxury towers on part of the cleared land. Around 200,000 families have been rehoused since 1995. The Dharavi Redevelopment Project, restarted in 2023, aims to clear and rebuild the iconic slum at a cost of US$3 billion.
Mumbai’s top-down strategies tackle the city at scale: Metro expansion (14 lines by 2030), the coastal road (2024), Vaitarna water supply (+455 million litres a day), electric buses (1,800 vehicles) and the Slum Rehabilitation Scheme.
Top-Down: Strengths and Weaknesses
Top-down has clear advantages. Big infrastructure projects can shift millions of people quickly — the Metro alone will cut hundreds of thousands of car journeys. Foreign investment and World Bank funding pay for projects too costly for the city alone. National prestige projects (the coastal road) deliver visible results that politicians can point to. But top-down has weaknesses: communities are sometimes evicted with little notice or fair compensation. Slum-rehabilitation tower blocks have been criticised for breaking up the tight-knit neighbourhoods that supported migrant families. Mega-projects also overrun on cost and time — the Mumbai-Ahmedabad bullet train was meant to open in 2022 but is still under construction.
Bottom-Up: Community and NGO Strategies
Bottom-up strategies work at the neighbourhood scale. They use intermediate technology, depend on local labour and are usually run with NGO support.
Housing & sanitation. The Indian NGO SPARC (Society for the Promotion of Area Resource Centres) works with the National Slum Dwellers Federation. Together they have built community toilet blocks in over 250 settlements and trained local women to manage them — a low-cost answer to the city’s open-defecation problem. Where eviction has been threatened, SPARC has negotiated for residents to design and co-finance their own replacement housing instead.
Recycling and the informal economy. Around 250,000 ragpickers in Mumbai recover, sort and resell the city’s waste. NGOs such as Stree Mukti Sanghatana have organised them into cooperatives, securing health insurance, ID cards and protective clothing. This recycles up to 40% of the city’s plastic waste — an environmentally sustainable solution that also raises informal-sector workers’ incomes.
Education and skills. The NGO Pratham runs after-school literacy and numeracy programmes for children of migrant workers, with hundreds of thousands of children supported across Maharashtra each year. Better-educated children are more likely to move into the formal sector, breaking the slum-poverty cycle.
Bottom-up projects are designed around what residents actually need. They cause little or no displacement and are easy to maintain — community toilets are repaired by the people who use them. They also create local jobs. But they are small-scale: SPARC’s 250 settlements are a fraction of Mumbai’s 8–9 million slum residents. They cannot build a Metro line. Funding depends on charity and international donors. And without policy support, gains can be reversed when developers want the land.
The most successful Mumbai schemes combine top-down and bottom-up approaches. The Slum Sanitation Programme, supported by the World Bank, uses NGOs to design and run toilet blocks but state funding to pay for construction. The Dharavi Redevelopment Project is being scrutinised by SPARC and resident committees to ensure rehoused families are not displaced or short-changed. Sustainable development in a megacity rarely works by one strategy alone.
SPARC builds community toilet blocks in over 250 settlements. Stree Mukti Sanghatana organises about 250,000 ragpickers, recycling up to 40% of Mumbai’s plastic waste. Pratham educates children of migrant workers across Maharashtra.