How Hyderabad’s lakes manage stormwater: HUL’s new Lake Atlas explained
HYDERABAD: Before Hyderabad was filled with concrete and traffic, natural features and generations of tank irrigation shaped the city’s landscape. Tank builders created an interconnected system of water bodies (known as tanks), channels, and floodplains. These features slowed down stormwater, allowed it to spread, recharged the groundwater, and sent surplus water to the river.
Hyderabad Urban Labs(HUL) now makes this hidden hydrological system visible online. In conversation with HyderabadMail, Researcher Teja Malladi associated with HUL explained that the new tool builds on an earlier Urban Observatory Platform, which only showed elevation and drainage network data. It did not include Hyderabad’s lakes. The new Lake Atlas fills this gap. It models how lakes connect to each other and to the broader stormwater drainage system, both upstream and downstream.
Specifically, the platform answers a simple question that is when rain falls in the city, where does it go? Teja said the tool can trace this path. It shows rain moving from where it lands, into a lake, then overflowing into the next lake, and so on until it reaches a river.
The city’s current drainage is more complicated than nature intended. Box drains and ring bunds, often built without considering the old lake network, now divert water away from lakes added Teja.
Additionally, the platform does more than trace drainage paths. It adds information useful for planning and public awareness. Users can see rainfall data included from automatic weather stations, count the number of buildings in each catchment area, and estimate rooftop rainwater harvesting potential.
Moreover, Teja said the main goal is to build awareness. Unmanaged rooftop runoff could be harvested, but instead it overwhelms stormwater drains and causes urban flooding when blockages occur.
One striking feature of the project is how it was built. Teja said all the platform’s data, including lake boundaries, digital elevation models (DEMs), river boundaries, rainfall records, and building footprints, is publicly available online. The team focused on integrating existing datasets to visualize the city’s hydrological response to rainfall, rather than generating new data.
#Hyderabad’s water systems were designed to store water. #Lakes overflowed into other lakes. Water slowed down, spread out,recharged the ground & eventually reached the river
We built lake atlas to explore this https://t.co/AjLzld27gQ@amaringanti @Amruthkiran94 @hulfoundation pic.twitter.com/XQP0THcyGz
— Teja Malladi (@tejamalladi) June 12, 2026
To illustarte, Teja compared the concept to bathroom design. A bathroom floor slopes so water drains toward one point. Similarly, every street and neighborhood has a slope that directs water. Anyone walking or cycling through Hyderabad has probably felt this slope, even if they didn’t notice its importance.
When people lack this understanding, problems arise in policy and infrastructure decisions. Examples include ring bunds that block inflows to lakes, neglected lake maintenance, and a general lack of attention to stormwater flow paths.
The Lake Atlas is part of a larger effort at Hyderabad Urban Labs. It belongs to the Urban Observatory initiative, a framework with three components including data repositories, research and advocacy, and physical and social interventions in communities.
Each part supports the others. Data repositories inform research and advocacy, which in turn guide interventions. Enable the design of intervention data to create a continuous feedback loop rather than isolated projects.
Further, Teja added that the Lake Atlas is an ongoing project for Hyderabad’s Urban Observatory platform. It serves both public education and technical research. There is no fixed endpoint. It is a public resource that continually evolves.
Commenting on the upcoming projects Teja said that Hyderabad Urban Labs will soon launch a flood incident reporting system for the city. It is expected to go live in a day or two. The system will be an open platform where residents can directly report flood events.
