Real-time data collected by researchers from IIT-Madras on water discharged at several critical places along the Adyar during Cyclone Nivar is expected to help in a crucial way in flood forecasting and mitigation in the future, a statement issued by the institution said.

According to the statement, a team of students and researchers led by Balaji Narasimhan, professor, IIT-M, measured river currents and flow depths across the width of the waterbody to get the integrated flow rate of the river.

K. Phanindra Reddy, Commissioner of Revenue Administration, Tamil Nadu, was quoted in the statement as saying that the data collected by IIT-M, in close coordination with the Tamil Nadu State Disaster Management Authority (TNSDMA), would be useful in operationalising the Real Time Flood Forecasting (RTFF) and Spatial Decision Support System (SDSS) being coordinated under the World Bank-assisted Tamil Nadu Sustainable Urban Development Project (TNSUDP).

The statement highlighted that the data collection project began after the Chennai floods in December 2015. Through this, a network consisting of 15 automatic weather stations, rain gauges and six water level recorders were established in 2017. However, as the years since 2017 witnessed below normal monsoon, sufficient data in terms of river discharge could not be collected.

Highlighting the outcome of the project, Mr. Narasimhan said this was an important exercise in calibrating and validating the developed flood forecasting models.

This could be used to forecast the discharge at the river based on rainfall predictions by the India Meteorological Department (IMD) with different lead times (from three hours to 72 hours or even longer), he said.

“The ground truth collected during this field campaign during Cyclone Nivar showed that certain parts of the Adyar contributed to up to almost 70% of the flow realised at Anakaputhur with the rest contributed by the release from the Chembarambakkam reservoir,” he added.

“Even more critical is that the collected data will be incredibly useful to manage and moderate the reservoir releases from Chembarambakkam, giving sufficient lead time for the TNSDMA to issue a warning to the public and coordinate flood mitigation and relief measures,” he said.