Bengaluru: Every monsoon, Bengaluru’s roads turn into rivers, vehicles stall in waterlogged streets and homes are inundated after just a few hours of heavy rain. Ironically, many of the city’s lakes remain dry despite the downpour.
For retired Army officer Captain Santosh Kumar, this contradiction led to a years-long mission to uncover why rainwater was no longer reaching Bengaluru’s lakes. His research has revealed that the city’s forgotten network of Raja Kaluves—ancient stormwater channels built centuries ago—could hold the answer to tackling both floods and water scarcity.
Ancient drainage network buried by urbanisation
After retiring from the Army in 2008, Captain Santosh returned to Muthanallur in Anekal Taluk and began investigating the decline of nearby lakes. Initially, he found that illegal extraction of lake water for tanker supply was contributing to the problem.
However, a detailed study between 2017 and 2019 revealed a much bigger issue. Many of the historic Raja Kaluves that once connected Bengaluru’s lakes had been encroached upon, built over or buried beneath roads and concrete during decades of rapid urbanisation.
Using British-era maps dating back to 1923, Captain Santosh traced the original water channels that had once allowed rainwater to flow naturally from one lake to another, recharging groundwater while preventing flooding.
Restoring forgotten waterways
Working alongside local residents, the Minor Irrigation Department and the Bengaluru Urban Deputy Commissioner, Captain Santosh helped restore nearly four kilometres of an ancient Raja Kaluve linking Muthanallur Lake and Battalakere Lake.
The restored channel revived one of the city’s historic water pathways that had disappeared beneath encroachments over the years.
When the next monsoon arrived, the results were striking. While neighbouring areas experienced flooding, Muthanallur remained largely unaffected as rainwater flowed through the revived channel into interconnected lakes instead of overflowing onto roads.
A model for Bengaluru’s future
Encouraged by the success, Captain Santosh expanded the initiative across Anekal Taluk, helping restore 14 ancient lakes, some believed to date back nearly 1,000 years, including the era of Rajaraja Chola I.
Experts believe Bengaluru’s estimated 800 kilometres of stormwater drains can become far more effective if historic Raja Kaluves are protected and restored instead of being encroached upon.
Captain Santosh says Bengaluru’s long-term resilience lies not in building more concrete drains but in reconnecting the city’s centuries-old water network, allowing rain to follow the natural paths it has travelled for generations.