Delhi govt to study impact of barriers, preventive steps for Yamuna flood

The Delhi government will undertake a five-month study to analyse the impact of obstructions like bridges, embankments, weirs, and river islands on the flow of Yamuna, officials familiar with the matter said on Monday, adding that the report will also suggest measures to prevent flooding in the river that inundated the Capital in July last year.

The Delhi government’s Irrigation and Flood Control Department (I&FC) has joined hands with the Central Water and Power Research Station (CWPRS) – an organisation under the Ministry of Jal Shakti – for the study, which will also assess the proposals by MLAs, MP and the I&FC department to create new embankments and retaining walls on the banks of the river. The study is estimated to cost ₹42.43 lakh.

“There are three proposals, one of which has also been moved by the local representatives. These include construction of another embankment (or bund) on the left bank of Yamuna from Wazirabad to Shastri Park parallel to the existing bund in continuity of left forward embankment up to the LM embankment near Shastri Nagar. Further, local MPs and MLAs have forwarded the demand for widening of left forward bund from Badarpur Khadar village to Nanaksar T-point in Wazirabad on the road,” a senior I&FC official said.

The third proposal pertains to the construction of an embankment or a retaining wall on the right bank of the river between Old Railway bridge and Wazirabad barrage.

This assessment of various long-term interventions is being undertaken in the wake of July 2023 flood when the river level had reached 208.66m mark – an all-time highest flood level recorded in the city – which was 1.17m higher than the previous record in 1978.

Flooding was witnessed at various locations between Wazirabad barrage and Okhla; the barrage on the right bank of the river near Chandi Ram Akhara, ISBT Kashmere Gate, Nigam Bodh Ghat, Shanti Van, Raj Ghat; and ITO among other places in the Capital.

The official said that the study will also help determine the new warning and danger levels that should be fixed as an early warning system in the Capital. The danger mark at the Old Railway Bridge, considered representative of Delhi, is 204.5m. High alerts are issued after this mark is crossed and evacuations are triggered after the danger level of 205.33m is touched in low-lying areas.

Another official explained that the exercise will include an assessment of topographical and cross-sectional data of the river which will be utilised to develop a one-dimensional and two-dimensional mathematical model.

“Major existing structures in the study area like bridges, barrages, and weirs, will be reproduced through mathematical models. Water levels and velocities will be computed with the help of the model,” the estimate submitted by the institute mentioned.

The scope of the study comprises nine points – three pertaining to embankments – and the rest on study of islands formed in river and corrective measures; assessment of location and extent for clearing the mud and sand mining in river bed between Wazirabad and Okhla to increase the river’s carrying capacity; corrective actions in solid approach roads of various bridges; review of danger and warning levels at Old Railway Bridge, and strengthening and raising of existing regulators and pumphouses.