Overview
- Thousands of carcasses have floated for days near Rawta village at the Delhi–Haryana border, with residents reporting darker, foul-smelling water and even fish washing into nearby fields.
- Activists and experts say a sudden drop in dissolved oxygen likely drove the deaths, triggered by untreated residential and industrial waste plus summer heat and low flow.
- Official monitoring backs severe contamination, with the Delhi Pollution Control Committee in March recording biological oxygen demand at 60 mg/l downstream and 115 mg/l at the Mungeshpur confluence, far above the 30 mg/l standard.
- The Najafgarh drain is Delhi’s biggest wastewater source to the Yamuna, responsible for 68.71% of discharges, and similar fish kills were logged in 2022, 2024, and 2025.
- The National Green Tribunal sought a time-bound plan in September 2025 after a separate fish kill, yet there is no clear public update on that directive, fueling calls for rapid testing, source tracing, and immediate cleanup.