POOR DRAINAGE, RAISED RIVER BED ADDED TO DELHI'S FLOOD WOES

This time, Yamuna saw a sharp rise in its water level due to incessant rains in the upper catchment areas.

- INDRANI GHOSH

Yamuna inundating its banks in Delhi is not new, it has happened on several occasions, an official of the Delhi Irrigation and Flood Control Department has said. In fact, floods or floodlike situations have been witnessed in Delhi and surrounding areas in 1924, 1977, 1978, 1995, 2010 and 2013, he said.

Analysis of flood data between 1963 and 2010 indicates there are more chances of flooding in September than in July. However, this time, Yamuna saw a sharp rise in its water level due to incessant rains in the upper catchment areas as a combination of key factors contributed to record precipitation in the Himalayas.

Delhi witnessed the highest rainfall (153 mm) in a single day in July since 1982 in a 24-hour period ending at 8.30 am on 9 July.

The city received 107 mm of more rain in the next 24 hours, further worsening the situation.

This caused a large amount of discharge from the Hathnikund barrage in Haryana. On 11 July alone, 3.59 lakh cusecs were released. Generally, what earlier used to take about two to three days for the water released to reach Delhi from the barrage in Yamunanagar, Haryana, around 180 km from the national capital, this time it "took less time to reach Delhi compared to previous years, due to encroachment and siltation. Earlier where there used to be more space for the water to flow, now, it passed through a restricted cross-section," said a senior official of the Central Water Commission (CWC).

International Union for Conservation of Nature (IUCN) country representative Yashvir Bhatnagar has attributed the record water level in the Yamuna to intense rainfall across the entire upper catchment area and called the excessive rainfall in a short period of time as the main reason for the Yamuna raging in Delhi.