PIB TrackerClean Ganga turns to 'Nature-based Solutions', piloting constructed wetlands to clean Delhi drains
The National Mission for Clean Ganga is mainstreaming Nature-based Solutions — launching two constructed-wetland pilots on Delhi's Shastri Park and Kailash Nagar drains (~10 MLD) that use plants, rock filters and phytoremediation to treat sewage with low energy before it reaches the Yamuna.
What happened
- The National Mission for Clean Ganga (NMCG) is mainstreaming Nature-based Solutions (NbS) to complement conventional sewage treatment.
- It launched two constructed-wetland pilots on Delhi's Shastri Park and Kailash Nagar drains (~10 MLD), both discharging into the Yamuna.
- The systems use rock filters, aquatic vegetation and phytoremediation to remove solids, nutrients and some heavy metals with low energy.
- They raise dissolved oxygen, cut organic pollution and boost biodiversity at lower operation and maintenance cost.
- The pilots are part of NMCG's Sustainable River Rejuvenation (SRR) programme, alongside sewerage/STPs and environmental flows (E-Flows).
For Prelims
- NMCG: The National Mission for Clean Ganga — the implementing arm of Namami Gange; a body under the Environment (Protection) Act-linked 2016 River Ganga order.
- Nature-based Solutions (NbS): Using natural processes/ecosystems (wetlands, forests) to solve challenges like pollution and flooding at lower energy cost.
- Constructed wetland: An engineered wetland that mimics natural ones to treat wastewater via plants, microbes and filtration.
- Phytoremediation: Using plants to absorb, stabilise or break down pollutants (including nutrients and heavy metals) in water/soil.
- Environmental flows (E-Flows): The minimum flow a river must retain to sustain its ecology — mandated for the Ganga.
- MLD: Million Litres per Day — the standard unit for water/sewage treatment capacity.
For UPSC: Anchor this in river rejuvenation and sustainable water management — NbS/constructed wetlands as low-energy, climate-resilient complements to STPs, and the shift to holistic river-basin management. Link Namami Gange/NMCG, E-Flows, phytoremediation and the circular, ecosystem-based approach to pollution abatement.
What it is NOT: This is a pilot-scale ecological intervention (two ~10 MLD drains), not a replacement for sewage-treatment infrastructure, which NMCG calls the cornerstone. NbS complements STPs and E-Flows; it is not by itself a full solution to river pollution.
For Mains
Syllabus: GS3.14 · Linkage L2
Anchor
Ecosystem-based, low-energy river rejuvenation — Nature-based Solutions complementing engineered treatment for resilient water management.
Substantiation (data)
NMCG's Sustainable River Rejuvenation programme pilots two constructed wetlands on Delhi's Shastri Park and Kailash Nagar drains (~10 MLD) using phytoremediation, into the Yamuna.
Exemplification
Constructed wetlands with rock filters and aquatic plants; E-Flows and STPs as the complementary pillars of holistic river-basin management.
Problematisation
NbS needs land, careful design and maintenance and works best at drain/tributary scale; it complements but cannot replace sewerage for large urban loads.
Way-forward
Scale successful pilots, combine NbS with STPs and E-Flows, and build research and capacity for wider adoption across the Ganga basin.
Position
Government stance: holistic, sustainable river-basin management blending engineering with nature under Namami Gange.
Deploys into: Conservation, environmental pollution and degradation (GS3.14 — river rejuvenation) · Namami Gange/NMCG, Nature-based Solutions, constructed wetlands, phytoremediation and environmental flows · sustainable, climate-resilient water management.
Ministry of Jal Shakti · 2026-07-09 · PRID 2282711 · PIB source ↗