2023 Delhi floods forecast inaccurate due to Yamuna congestion: Govt to NGT

The Centre has informed the National Green Tribunal the 2023 flood forecast by the Central Water Commission was inaccurate due to the congestion in River Yamuna between Wazirabad and Okhla barrages.

The green body had taken a suo motu cognisance of a newspaper report and sought a response of the Union Ministry of Jal Shakti (MoJS), Central Water Commission (CWC) and others over the failure of the commission to predict Delhi witnessing its worst floods in 2023.

In 2023, Delhi witnessed one of its worst flood-like situations in several pockets due to heavy rains and over 25,000 people were evacuated from inundated areas.

The reply filed by the MoJS and CWC on January 4 said the high discharge downstream of Hathnikund Barrage created a flood situation in River Yamuna near Delhi.

"Due to this, the flow of the Delhi Railway Bridge (DRB) site increased continuously and crossed the previous high flow level (HFL) of 207.49 metre at 13:00 (1 pm) hrs on July 12, 2023, and achieved the highest peak water level of 208.66 metre at 18:00 (6pm) hrs on July 13," it said.

The flood forecast, it said, required the water channel to be in a "free flow state" and changes in flow conditions upstream and downstream of the flood forecasting station could "compromise" accuracy.

It said the free flowing conditions did not exist between Wazirabad and Okhla barrages because of the non-opening of all the gates of ITO Barrage, the formation of islands of silt deposits, trees in the river's course and muck disposal at various locations due to bridge construction activities across the river.

"All these factors resulted in congestion in the river in Delhi reach and if the free flow condition of the channel is compromised, then, the forecast issued will not match with the actual forecast," the reply said.

A committee headed by the CWCs chairperson suggested the departments concerned in Delhi to take corrective measures for the future, it said.