A missing flush: Yamuna fails to hit warning level this monsoon

The Yamuna river in Delhi has not yet reached even its modest warning level during this year's monsoon season, according to official data. This has raised concerns among experts that the river may have missed its annual monsoon flush, which is crucial for its ecological health and groundwater replenishment in floodplains. Typically, the river swells significantly during the four-month monsoon cycle, but at the Old Railway Bridge (ORB) on Thursday, the water level stood at 202.52 meters.

The Central Water Commission predicts steady levels for the next week, with the warning level set at 204.50 meters and the danger level at 205.33 meters. Bhim Singh Rawat, coordinator of SANDRP, noted that the river has experienced an unusually dry monsoon so far, with no instances of reaching the 204.5-meter level. This, coupled with erratic rainfall in the upper catchment area, may be linked to the diversion of most river water to Eastern and Western Jamuna canals rather than allowing it to flow downstream.

Rawat emphasized that the monsoon is the only period when the river receives enough water to flush pollutants downstream, which is vital for its long-term ecological health. Experts highlight that the river's annual swelling is important for maintaining ecological balance, supporting aquatic life, and recharging groundwater aquifers beneath the floodplains.

Low-level flooding allows water to spread across the floodplain, aiding groundwater recharge. The National Institute of Hydrology has recommended doubling the minimum flow during summer to ensure environmental flow in the river. The Yamuna reached 204.08 meters on August 8, just below the warning level, a level it has only managed to reach twice in the past decade.