Bengaluru Rajakaluve Buffer Zones Under Threat: Activists Warn the City Could Become Unlivable

If approved, this move could turn the city’s natural drainage system into a recipe for disaster.

What’s Being Proposed?

Bengaluru has nearly 1,000 km of rajakaluves — the ancient network of natural drains that channel stormwater from one lake to another and eventually to rivers. Historically, these drains were safeguarded by massive buffer zones of 500 to 1,000 metres on either side.

Current rules mandate:

• 50 metres for primary drains
• 35 metres for secondary drains
• 25 metres for tertiary drains

The new Draft Regulation No. UDD 468 MNJ 2025 (E) wants to cut these drastically to:

• 15 metres for primary drains
• 10 metres for secondary drains
• Just 5 metres for tertiary drains

Smaller drains feeding into tertiary ones would get no buffer at all — only whatever is marked in revenue records.

Why This Is a Terrible Idea

Activists and environmentalists are sounding the alarm, calling the proposal “unscientific, unsustainable, and unacceptable.”

Sandeep Anirudhan, Convenor of Bengaluru Town Hall, a prominent citizens’ group, submitted a strong memorandum against the changes. He warns:

“It will most certainly increase flooding risks in an already battered Bengaluru. It poses a grave threat to the barely remaining green cover… could lead to the extinction of the last remaining green cover, pollution of stormwater drains and lake waters, erase biodiversity, deepen climate change impacts, and worsen our groundwater crisis.”

He adds bluntly:

“This will leave Bengaluru a concrete desert, unlivable for all of us.”

A Perfect Storm with Lake Buffer Cuts

This proposal comes right after the controversial KTCDA Amendment Bill 2025, which attempted to weaken buffers around lakes and smaller water bodies. The Governor sent that bill back for review following public outcry.

Environmental researcher Nirmala Gowda (Founder of Mapping Malnad) points out that combining weaker lake and drain buffers creates a dangerous situation. In her detailed open letter, she highlights how these changes contradict:

• The Karnataka Tank Conservation Act’s own requirement to maintain original water body capacity
• CAG audit findings
• Multiple High Court and Supreme Court orders (including a mandatory 30-metre buffer)
• Constitutional environmental protections
• The city’s own Bengaluru Climate Action and Resilience Plan

She emphasises:

“Buffers are not empty spaces — they are living ecological systems that perform vital hydrological functions, including flood moderation, groundwater recharge, and sediment control.”

What Should Happen Instead?

Citizen groups are demanding the government withdraw the notification immediately and actually increase buffer zones rather than shrink them. International research suggests buffers of 100–300 metres or more are needed for healthy stormwater systems, flood control, and water quality.

The Bigger Picture

Bengaluru’s lakes and rajakaluves aren’t just scenic features — they are the city’s lifelines. They manage floods during heavy rains, recharge groundwater, support biodiversity, and provide the only remaining breathing space in a rapidly concretising city.

Weakening their protection for short-term development gains risks long-term pain: more frequent and severe flooding, worsening water shortages, polluted lakes, and a city that becomes increasingly difficult to live in.

The message from activists is clear: Bengaluru doesn’t need more concrete poured over its drains. It needs wiser, science-backed urban planning that respects the city’s natural infrastructure.

What do you think? Should the government listen to citizens and experts on this? Share your views in the comments.

Let’s hope decision-makers choose a livable future for Bengaluru over unchecked concretisation.