Yamuna: Clean River or Clean Report?

New Delhi: The Delhi Pollution Control Committee (DPCC) recently released a report claiming a significant breakthrough in the fight to clean the Yamuna River — a reported 90%+ drop in fecal coliform levels. At first glance, this seems like a major success for the government’s multi-crore rejuvenation projects. But a closer look at the data reveals a puzzling contradiction.

Despite this apparent improvement in bacterial contamination, other critical pollution parameters show no sign of recovery. Key indicators such as Biochemical Oxygen Demand (BOD), Chemical Oxygen Demand (COD), and Total Suspended Solids (TSS) — all crucial markers of water quality — remain unchanged. This discrepancy has raised eyebrows among environmentalists and legal activists who have long tracked the capital’s pollution woes.

One such voice is that of activist Pankaj Kumar, who has publicly questioned the credibility and interpretation of the data. “How can fecal coliform levels drop so drastically when BOD and COD levels remain high? These indicators are interrelated. If the river is truly getting cleaner, all parameters should show consistent improvement,” he remarked. His concerns hint at a deeper issue: whether this selective improvement reflects an actual change on the ground or a selective reporting strategy aimed at showcasing partial success.

Supporting his skepticism, the February and March 2025 performance reports of Sewage Treatment Plants (STPs) tell a different story. Out of 36 STPs operational in Delhi, only 12 were found to be complying with the prescribed discharge norms in March. A significant number of these plants still release effluents with high levels of BOD and COD, pollutants that directly affect aquatic life and human health.

Fecal coliform, a type of bacteria commonly found in human and animal waste, is often treated as a key indicator of recent sewage contamination. A sharp decline in its levels could mean better disinfection or less untreated sewage entering the river. But without improvements in organic and chemical load (reflected in BOD and COD), the water can still remain unfit for most uses.

So, what could explain this selective improvement?

One possibility is the temporary efficacy of disinfection methods like chlorination, which can reduce bacterial presence but do little to address chemical and organic pollution. Another is that fecal coliform levels were specifically targeted for reduction to create an impression of progress. Or it could indicate deeper structural inefficiencies in the sewage treatment process — where bacteria are eliminated but chemical loads continue to bypass treatment due to overburdened or malfunctioning plants.

The gap between bacterial and chemical treatment efficiency raises serious questions about how pollution control efforts are being measured, reported, and communicated to the public. If only certain metrics improve while others stagnate, it can lead to a misleading narrative of success.

As legal and environmental watchdogs continue to scrutinize these developments, one thing is clear: a cleaner Yamuna cannot be built on selective data. Transparency, comprehensive treatment, and consistent monitoring across all pollution parameters are essential for genuine progress.