Regional spotlight: Desalination & advanced water treatment in India — what's different and why it matters

India faces a water crisis of extraordinary scale. The country holds 18% of the world's population but only 4% of its freshwater resources, and the Central Water Commission projects that demand will exceed available supply by nearly 50% before 2030. Groundwater, which provides drinking water for roughly 85% of the rural population and 50% of urban areas, is depleting at alarming rates across the Indo-Gangetic plain, Rajasthan, and southern peninsular states. The 2024 NITI Aayog Composite Water Management Index ranked 21 major cities at risk of reaching "Day Zero" conditions within the decade. Against this backdrop, desalination and advanced water treatment have moved from peripheral technologies to central pillars of India's water security strategy, but the country's approach differs fundamentally from the Gulf or Mediterranean models that dominate global industry narratives.

Why India's Context Is Distinct

The global desalination industry, valued at approximately $20.1 billion in 2025 according to DesalData, is dominated by Middle Eastern and North African deployments where energy is cheap, coastlines are arid, and per-capita income supports high water tariffs. India's reality inverts nearly every assumption embedded in those models.

First, affordability constraints are severe. India's average household monthly income sits near $450, and willingness to pay for treated water rarely exceeds INR 5-8 per kiloliter in urban settings and far less in rural areas. Compare this with Saudi Arabia, where desalinated water is priced at $0.80-1.20 per cubic meter with heavy government subsidization, or Israel, where Sorek B produces water at $0.40 per cubic meter for a population accustomed to paying market rates. Indian municipalities typically charge INR 4-12 per kiloliter for piped water, often below the cost of conventional treatment, let alone desalination.

Second, energy costs fundamentally reshape project economics. India's industrial electricity tariff averages INR 7-9 per kWh, roughly two to three times higher than the rates available to Gulf desalination plants powered by subsidized natural gas or captive power. Since energy accounts for 35-50% of reverse osmosis desalination operating costs, Indian plants face a structural cost disadvantage that requires creative solutions around renewable energy integration, waste heat recovery, and energy-efficient membrane technologies.

Third, India's coastline of 7,517 kilometers serves predominantly tropical, monsoon-driven regions where intake water conditions differ markedly from arid coast installations. High turbidity during monsoon months, elevated biological oxygen demand, seasonal temperature swings of 15-20 degrees Celsius, and periodic red tide or algal bloom events demand robust pretreatment systems that add 15-25% to capital costs compared with standard Gulf configurations.

Regulatory and Policy Landscape

India's water governance operates across a complex multi-layered framework that creates both opportunities and friction for desalination deployment. Water is constitutionally a state subject, meaning that policy, pricing, and allocation decisions rest with individual state governments rather than the central government. This fragmentation produces wide variation in regulatory environments across coastal states.

Tamil Nadu has emerged as India's desalination leader, driven by the Chennai Metropolitan Water Supply and Sewerage Board (CMWSSB). The state operates two major seawater reverse osmosis (SWRO) plants: the 100 MLD Minjur facility commissioned in 2010 and the 150 MLD Nemmeli plant operational since 2013. A third plant at Perur with 150 MLD capacity reached commissioning in 2024, and a 400 MLD facility at Nemmeli Phase II is under construction with a target completion date of 2027. Tamil Nadu's willingness to absorb desalinated water costs into blended municipal tariffs provides a replicable financing model, though political sensitivity around water pricing remains a persistent challenge.

Gujarat's approach leverages industrial demand as an anchor customer. The Dahej and Mundra coastal industrial corridors consume desalinated water at INR 50-70 per kiloliter, prices that industrial users accept because the alternative is trucked water at INR 80-120 per kiloliter. The Gujarat Industrial Development Corporation (GIDC) has facilitated public-private partnership structures where industrial offtake underwrites plant economics and surplus capacity serves municipal needs at subsidized rates.

Maharashtra's Brihanmumbai Municipal Corporation (BMC) approved a 200 MLD SWRO plant at Manori in 2023, marking Mumbai's entry into desalination after decades of reliance on dam-fed surface water from increasingly stressed Sahyadri reservoirs. The project's estimated capital cost of INR 5,200 crore (approximately $620 million) reflects the premium associated with land acquisition in Mumbai's constrained coastal zone and the stringent environmental clearance requirements under the Coastal Regulation Zone (CRZ) Notification of 2019.

The CRZ framework represents India's most significant regulatory constraint on desalination expansion. The notification classifies the coastal zone into four categories with varying development restrictions, and desalination plants must navigate CRZ-II or CRZ-III clearances depending on location. Environmental impact assessments require evaluation of brine discharge impacts on marine ecosystems, thermal plume modeling, and intake impingement studies. The clearance process typically adds 18-30 months to project timelines, a delay that frustrates urgency-driven procurement but provides environmental safeguards absent in many competing markets.

The National Green Tribunal (NGT) has imposed additional conditions on brine management. A 2023 NGT order mandated that all new desalination plants with capacity exceeding 50 MLD must demonstrate brine dilution to within 5% of ambient seawater salinity within 100 meters of the discharge point, or implement zero liquid discharge (ZLD) systems. This requirement, stricter than regulations in most Gulf states, has driven innovation in brine concentration and mineral recovery but adds 8-15% to project capital costs.

Market Dynamics and Investment Flows

India's desalination installed capacity stood at approximately 1,850 MLD as of late 2025, a fraction of Saudi Arabia's 7,500 MLD or the UAE's 3,200 MLD, but growing rapidly. The Ministry of Jal Shakti's Jal Jeevan Mission, which targets functional household tap connections for all rural households, has catalyzed investment in community-scale desalination for brackish groundwater zones, particularly in Rajasthan, Gujarat, and Andhra Pradesh.

Brackish water reverse osmosis (BWRO) represents a distinctly Indian growth segment largely absent from global desalination narratives. Approximately 60% of India's groundwater contains total dissolved solids (TDS) exceeding 500 mg/L, with large swaths of western and southern India showing TDS levels of 2,000-10,000 mg/L. BWRO systems treating brackish groundwater operate at energy intensities of 0.5-1.5 kWh per cubic meter, compared with 3.0-4.5 kWh per cubic meter for seawater RO, making them economically viable at scales as small as 10-50 kiloliters per day. Under the Jal Jeevan Mission, over 3,200 community BWRO plants have been commissioned since 2020, primarily in Rajasthan and Andhra Pradesh, serving populations of 500-5,000 people per installation.

Foreign investment has concentrated on large-scale SWRO projects. IDE Technologies (Israel) partnered with VA Tech Wabag to deliver the Chennai Nemmeli plant. Acciona Agua (Spain) won the Perur plant contract through a design-build-operate-transfer (DBOT) structure with a 15-year operating concession. Doosan Heavy Industries (South Korea) has bid on multiple Gujarat coastal projects. These international firms bring proven technology platforms but must adapt to Indian procurement frameworks, which typically prioritize lowest cost over lifecycle performance, creating tensions around quality and long-term reliability.

Domestic players occupy an increasingly significant share. VA Tech Wabag, headquartered in Chennai, has grown into one of the world's 15 largest water treatment companies by revenue, with desalination expertise spanning SWRO, thermal desalination, and hybrid configurations. Thermax provides industrial water treatment and ZLD solutions. Ion Exchange India delivers BWRO systems for community and industrial applications. These firms possess local engineering capacity, procurement networks, and regulatory navigation expertise that create meaningful advantages in India's fragmented market.

Private equity and infrastructure fund interest has accelerated since 2023. The India Water Impact works program, supported by the Asian Development Bank and World Bank, has mobilized commitments exceeding $2 billion for water infrastructure including desalination. InfraVia Capital, Macquarie Infrastructure, and Brookfield Asset Management have all evaluated Indian desalination opportunities, though most have paused at the due diligence stage, citing tariff uncertainty, counterparty credit risk with state water utilities, and currency exposure as primary concerns.

Technology Adaptation and Innovation

India's desalination sector has generated several technology adaptations driven by local conditions that are beginning to influence global practice.

Solar-powered desalination has moved beyond pilot stage in India faster than in most markets. The Solar Energy Corporation of India (SECI) collaborated with the Ministry of Jal Shakti to deploy 50 solar-RO community plants across Rajasthan between 2022 and 2025, using photovoltaic arrays directly coupled to BWRO membranes without grid connection. These off-grid systems produce water at INR 30-45 per kiloliter, competitive with tanker-delivered water in remote communities. The model has attracted interest from sub-Saharan African governments facing similar off-grid water challenges.

Membrane bioreactor (MBR) and advanced oxidation process (AOP) combinations for wastewater reclamation represent India's fastest-growing advanced treatment segment. The Bangalore Water Supply and Sewerage Board's 90 MLD tertiary treatment plant at KC Valley, operational since 2022, produces recycled water meeting industrial cooling standards at INR 18 per kiloliter, roughly one-third the cost of desalinated seawater. Delhi, Hyderabad, and Pune have all commissioned or tendered MBR-based reclamation projects exceeding 50 MLD capacity since 2024.

The emphasis on wastewater reclamation reflects a pragmatic recognition that India's most cost-effective path to water security often bypasses desalination entirely. The Central Pollution Control Board estimates that Indian cities generate approximately 72,000 MLD of sewage, of which only 28% receives any treatment. Upgrading existing treatment infrastructure to tertiary standards through MBR, AOP, or ceramic membrane systems can produce reusable water at 30-50% of desalination costs while simultaneously addressing pollution of rivers and groundwater.

What Investors Should Watch

Several indicators will shape India's desalination investment trajectory over the next three to five years.

Tariff reform remains the critical variable. States that implement volumetric water pricing at cost-reflective rates will attract private capital; those maintaining flat subsidies will continue relying on public finance with associated delays and budget constraints. Tamil Nadu's blended tariff model, which cross-subsidizes desalinated water costs across all municipal connections, offers a politically feasible middle path.

The Jal Jeevan Mission's extension beyond its 2024 target date, which the Ministry confirmed in the 2025-2026 Union Budget with an allocation of INR 70,000 crore, ensures continued central government funding for community-scale treatment. Investors focused on BWRO equipment manufacturing, membrane supply, and operations and maintenance services stand to benefit from this sustained demand signal.

Brine valorization represents an emerging opportunity. India's chemical industry consumes significant quantities of sodium chloride, magnesium compounds, and potassium salts that can be extracted from desalination brine. Several pilot projects in Gujarat are demonstrating salt recovery economics that reduce net brine disposal costs by 40-60%, potentially converting a waste management expense into a revenue stream.

Action Checklist

• Evaluate state-level water policy frameworks before site selection, prioritizing Tamil Nadu, Gujarat, and Maharashtra for regulatory maturity
• Model project economics using India-specific energy costs (INR 7-9 per kWh industrial tariff) rather than Gulf benchmarks
• Assess CRZ clearance timelines and brine discharge requirements during feasibility, budgeting 18-30 months for environmental approvals
• Consider hybrid models combining desalination with wastewater reclamation to optimize blended water cost per kiloliter
• Engage with Jal Jeevan Mission procurement channels for community BWRO opportunities in rural markets
• Structure tariff agreements with inflation indexation and currency protection clauses to mitigate long-term revenue risk
• Investigate brine valorization pathways as supplementary revenue streams, particularly for Gujarat coastal installations

Sources

• NITI Aayog. (2024). Composite Water Management Index 3.0: Performance of States and UTs. New Delhi: Government of India.
• Central Water Commission. (2025). National Water Resources Assessment: Supply-Demand Projections to 2030. New Delhi: Ministry of Jal Shakti.
• DesalData. (2025). Global Desalination Market Forecast and Country Analysis: India. Oxford: Media Analytics Ltd.
• Ministry of Jal Shakti. (2025). Jal Jeevan Mission: Annual Progress Report 2024-2025. New Delhi: Government of India.
• Central Pollution Control Board. (2024). National Inventory of Sewage Treatment Plants: Status Update. New Delhi: CPCB.
• Asian Development Bank. (2024). India Water Sector Assessment: Financing Gaps and Investment Opportunities. Manila: ADB Publications.
• VA Tech Wabag. (2025). Annual Report 2024-2025: Desalination and Water Reuse Portfolio. Chennai: VA Tech Wabag Ltd.