A brief evening downpour on Saturday added an impressive 2.1 million litres of water to two lakes on Bengaluru’s southern outskirts. This was recorded by SayTrees, a city-based NGO, using advanced solar-powered radar sensors installed at Handenahalli and Sollepura lakes.

According to Kapil Sharma, the NGO’s founder, the lakes accumulated this significant volume in just one day. He shared on X that they are preparing 10 lakes in Bengaluru, two in Hyderabad, and 15 in Maharashtra to capture more rainwater during the monsoon.

Lt Cdr Deokant Payasi (Retd.), CEO of SayTrees, revealed that four high-tech sensors were imported from the Netherlands since no Indian company currently offers solar-powered radar-based models. These devices, mounted on poles within the lakes, provide real-time water level data. “If there’s a sudden drop, we can detect leaks and take immediate action,” he explained.

Following Saturday’s rainfall, Handenahalli Lake’s water level rose by 0.02 meters, while Sollepura Lake saw an increase of 0.01 meters. Over the past year, SayTrees has restored these lakes by desilting, clearing inlets and outlets, repairing bunds, and fencing them to prevent pollution.

“The fact that two lakes filled with 2.1 million litres in one rain shows that proper rainwater harvesting can significantly recharge borewells,” Payasi emphasized.