Why Shrinking Lake Buffer Zones Undermines Bengaluru’s Entire Flood Strategy

Posted on January 5, 2026

Every monsoon, Bengaluru watches the same story repeat itself: neighbourhoods like Bellandur, Yelahanka and Koramangala go under water, despite crores already being spent on drains and lake restoration. In this context, the Karnataka Tank Conservation and Development Authority’s (KTCDA) recent proposal to reduce legal buffer zones around lakes and stormwater drains is deeply contradictory. These buffers were created to protect natural drainage routes and are a foundational part of the city’s flood-management approach. Shrinking them now means weakening the very systems the government is trying to strengthen.

Bengaluru’s flood strategy explicitly relies on preserving ecological buffers. The city’s resilience planning, through projects funded by both the state and the Government of India, focuses on widening stormwater drains, desilting lakes, restoring urban wetlands and maintaining the chain-lake system that historically handled rainwater. Under the Urban Flood Risk Management Programme, the city has already secured roughly ₹275 crore from central and state sources for flood management works, with funds released zone-wise depending on vulnerability assessments. These funds support structural improvements, but they also prioritise nature-based interventions such as recharge wells, stormwater-linked lakes, desilting and long-term lake management. Bellandur and Yelahanka, among the worst flood zones, are specific programme targets.

Government policy documents, including the Bengaluru Climate Action and Resilience Plan, state clearly that maintaining buffers is as critical as building drains, because buffers allow lakes and stormwater channels to function as "sponge spaces." They absorb excess water, enable groundwater recharge, protect natural outlets and moderate rainfall events instead of pushing water across paved surfaces. In fact, the city’s resilience strategy openly emphasises working with traditional water networks rather than relying only on engineering solutions.

Multiple recent studies have quantified the benefits of nature-based solutions. A 2024 analysis showed that implementing green roofs and recharge wells across roughly 25% of the urban area could reduce runoff volume by almost 45% and cut very high flood-risk zones by as much as 77%. These results are significant, because they show that even partial adoption of nature-based strategies has outsized impact. But all such measures depend on one basic principle: water needs space. Without adequate buffers around lakes and drains, overflow has nowhere to go except roads, basements and low-lying neighbourhoods.

The contradiction becomes sharper when you look at the broader funding landscape. Bengaluru is currently receiving hundreds of crores not just from India’s disaster-mitigation budgets but also from major external programmes, including World Bank-supported urban water projects. These are framed around long-term resilience, integrating lake rejuvenation, data-driven flood modelling, early-warning systems and citizen-engagement for solid waste management. The city has also publicly stated that flood prevention must go beyond insurance and short-term compensation, shifting towards systemic resilience with both hard engineering and soft ecological interventions. That shift depends on increasing, not decreasing, protective lake buffers.

Reducing buffers invites more construction closer to waterways, increases runoff and accelerates encroachment, exactly what caused many earlier flood disasters in Bengaluru. It weakens groundwater recharge, undermines water quality, and pushes the city back toward the pattern of rapid surface runoff that overwhelms drains. It also directly contradicts legal guidelines and earlier judicial directions, including National Green Tribunal rulings that stressed the ecological role of buffers and mandated protections for waterbodies and stormwater channels.

More importantly, shrinking buffers doesn’t just worsen flooding; it also aggravates water scarcity. The city’s “natural alignment” strategy of reinforcing interlinked lakes, wetlands and aquifers depends on keeping catchments intact so excess rain is absorbed instead of wasted. Without buffers, lakes lose their wetland zones, and aquifers beneath them cannot recharge effectively. This means Bengaluru becomes more flood-prone and more drought-prone at the same time, a dangerous combination already visible in alternating months of surplus and shortage.

At a deeper level, the proposed buffer reduction undermines the logic and purpose of every existing flood-mitigation project. Bengaluru’s resilience plans, from BBMP’s flood works to climate-resilience roadmaps, are built around restoring blue-green infrastructure, strengthening ecological flows and investing in natural solutions rather than constantly retrofitting drains. These are high-investment, long-term shifts meant to transform the city’s relationship with water. Weakening buffers does the opposite: it pulls Bengaluru back into expensive emergency works, ad-hoc pumping, contaminated lakes and annual flood-response spending.

Ultimately, the city cannot claim to be building resilience while simultaneously dismantling the ecological protections that resilience depends on. If Bengaluru is serious about long-term flood safety, climate adaptation and groundwater security, buffer zones cannot be treated as buildable margins. They are hydrological infrastructure, as essential as drains, pipelines or reservoirs. Shrinking them undermines science, contradicts policy, and erases the ecological room that water requires. In the simplest terms, Bengaluru is spending hundreds of crores trying to prevent floods, and then clearing the way for floods in the very next policy breath.

If the city truly wants to be flood-resilient, protecting buffer zones is not optional, it's the foundation on which every other measure stands.

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