Buffering Karnataka’s waterbodies

In the precocious concluded monsoon session, the Karnataka authorities introduced the Karnataka Tank Conservation and Development Authority (Amendment) Bill, 2025, which amends the 2014 Act to specify graded buffer zones astir tanks based connected their size, from 0 m for tanks nether 0.05 acres to 30 m for tanks implicit 100 acres. Following this, the Urban Development Department issued a draught notification reducing the buffer zones of storm-water drains.

While determination is nary universally accepted explanation of buffer zones, successful galore countries they are designated areas astir waterbodies intended to minimise the antagonistic impacts of quality settlements. From an ecological perspective, buffer zones are considered “protected zones” that assistance mitigate the effects of quality enactment and onshore disturbance, portion besides providing captious habitats for food and different wildlife.

Earlier versions of the Karnataka Tank Conservation and Development (KTCD) Act did not explicitly notation buffer zones, alternatively referring to the areas astir waterbodies arsenic “no-construction zones”. Essentially, buffer zones tin beryllium understood arsenic no-construction areas oregon greenish belts that enactment captious ecological functions, including nutrient absorption, wildlife situation preservation, and attraction of h2o quality.

The amended Bill

The amended KTCDA Bill was debated successful some Houses. It passed the archetypal hurdle, but it failed to person assent from Governor Thaawar Chand Gehlot aft a civic radical filed objections, highlighting the antagonistic outcomes of the “unscientifically” drafted Bill. Following this, some moves by the authorities attracted wide criticism, with activists calling the amendment “pro-real estate” and a systematic demolition of h2o bodies astatine a clip erstwhile lakes are becoming a portion of history.

N.S. Boseraju, Minister of Minor Irrigation and Science and Technology, told The Hindu that the State has 41,800 waterbodies, 90% of which are small. About 22,000 waterbodies nether panchayat raj attraction span little than 5 to 10 acres, helium said.

“As astir of these waterbodies are successful agrarian areas, farmers person suffered from the buffer portion rule, particularly those who ain fractional an acre oregon adjacent smaller plots adjacent lakes,” Boseraju said. “Even the absorption has travel from municipality civic groups successful Bengaluru, wherever determination are 220 existing lakes, astir of them larger ones, and the buffer portion remains the aforesaid for them, fundamentally meaning nary impact,” helium added.

However, preliminary appraisal of waterbodies information successful Western Ghats districts by Nirmala Gowda, activist-researcher, Mapping Malnad, revealed that reducing buffer zones volition disproportionately interaction smaller lakes owed to broad simplification of harmless spaces.

“In the Western Ghats, wherever developmental projects are successful afloat swing, determination is simply a precocious hazard of lakes filling with silt. These areas person much kattes and kuntes (smaller lakes), which play a important relation successful recharging groundwater levels. If they vanish, it volition airs a nonstop menace to the affluent excavation of taxon and to farmers successful the area,” Nirmala told The Hindu, adding that it is unclear however the section volition forestall encroachments erstwhile humanities patterns amusement that h2o bodies are highly vulnerable.

Adding to Nirmala’s findings, V. Ramprasad of Friends of Lakes questioned whether buffer zones adjacent beryllium anymore. He specifically pointed retired encroachments of stormwater drains successful Bengaluru.

Ramprasad’s observations are reflected successful records of the erstwhile BBMP Lakes Department and the 2021 Comptroller and Auditor General of India (CAG) report, which reprimanded the civic assemblage for neglecting stormwater drains successful the city.

“Bengaluru witnessed large-scale encroachment of lakes and drains and depletion of earthy drainage systems. Changes successful onshore use, specified arsenic a alteration successful vegetation screen and unfastened spaces and an summation successful built-up areas, resulted successful nonaccomplishment of interconnectivity betwixt waterbodies, impacting effectual groundwater recharge and expanding stormwater runoff,” the CAG study said.

To illustrate, according to archetypal 1976 documents referred to by the BBMP, Kacharakanahalli Lake spanned 56 acres, but lone 16 acres remained erstwhile rejuvenation began. Over the years, a temple spot and a sports analyzable had encroached connected the lake, portion astir 1,200 migrant workers lived successful 435 makeshift houses built connected the water area, who are present being relocated to antithetic places.

In addition, the State Economic Survey 2025 highlighted the dependence connected underground h2o for agriculture. In 2015, astir 37% of cultivation activities relied connected groundwater accessed done borewells. By 2025, this fig astir doubled to 60%, highlighting the grade of earthy assets depletion.

Moreover, Karnataka is among the apical 9 States successful the state that gully heavy connected underground water. On average, 68% of h2o utilized successful the State comes from underground sources, compared to the nationalist mean of 60%. This underscores the dependency connected and value of maintaining groundwater levels, which is intimately linked to the preservation of h2o bodies and, indirectly, to buffer zones.

What is the caller rule?

By reducing the buffer zone, the caller Act permits the operation of nationalist inferior infrastructure specified arsenic roads, bridges, h2o proviso lines, electrical poles, pump houses, and sewage attraction plants wrong vessel areas, including the abstraction betwixt afloat and maximum vessel levels, provided that h2o travel and capableness are not affected. Commercial, recreational, and concern activities, however, stay mostly restricted.

Earlier, Karnataka had a azygous buffer portion of 30 m for lakes and different waterbodies, portion storm-water drains (SWDs) had a 50-m buffer, careless of size. The amendment present introduces antithetic buffer zones based connected the size of the lakes.

Minister Boseraju described the Bill arsenic “progressive”, noting that it establishes amended buffer portion rules compared to neighbouring States.

“Irrespective of the size of a lake, Tamil Nadu has acceptable a buffer portion of 3 m, and it is 9 m successful Telangana. In contrast, we antecedently had 30 m, and present we person a size-based matrix, which ensures ecological conservation portion allowing development,” helium told The Hindu.

B.K. Pavitra, Secretary to the Government, Department of Minor Irrigation and Ground Water Development, explained that the amendment was prompted by concerns raised by MLAs from agrarian areas regarding the “irrational rules” of the erstwhile azygous 30-m buffer for each waterbodies, which hindered imaginable development.

“An MLA from the Kundapura loop flagged that adjacent Kuntes (smaller h2o bodies) of 2 acres had a 30-m buffer zone, restricting farmers with adjacent onshore and limiting improvement opportunities. We compared buffer zones successful different states and realised our rules were irrational,” Pavitra said.

He added that pursuing these concerns, Chief Minister Siddaramaiah acceptable up a committee led by Chief Secretary Shalini Rajneesh and heads of enactment departments, including municipality section bodies and civic authorities.

“During the committee meeting, each technological points were discussed, and buffer zones successful antithetic States were compared. We concluded that buffer zones tin beryllium reduced based connected the size of h2o bodies,” helium said, adding that the simplification of storm-water drain buffer zones was discussed during this meeting.

Minister Boseraju further emphasised that the departments volition not authorise immoderate operation successful the buffer zones without strict oversight, ensuring vigilance against amerciable construction.

Activists rise concern

However, activists reason that this is simply a anemic justification to walk the Bill, arsenic the State has historically been inactive against encroachments.

Nirmala points to a cardinal occupation successful the government’s mentation of the law. She stresses that the instrumentality should beryllium interpreted successful airy of its purpose—protecting and conserving lakes—but successful this case, it has not been. Public infrastructure projects that bash not straight service the lake, specified arsenic its restoration, maintenance, oregon ecological health, should not autumn nether the Act.

“For instance, if you’re gathering a span that has thing to bash with the lake, however does the Act let it? Provisions indispensable beryllium interpreted successful airy of the law’s halfway objective, which is water conservation. Otherwise, these interpretations hazard undermining the precise intent of the legislation,” Nirmala explained.

Experts constituent retired that earlier the authorities compares States oregon draws legislative parallels, due interaction assessments are needed. They reason that a just examination requires systematic studies of on-the-ground conditions, which the KTCD Act is designed to conduct, but nary person been carried retired truthful far.

A authorities root confirmed that isolated from humanities documents and interstate comparisons, the section has not conducted immoderate technological tract studies.

Ecological importance

Buffer zones astir lakes and waterbodies supply aggregate captious functions. They service arsenic habitats for birds, amphibians, and semi-aquatic species, supporting feeding, nesting, and resting. These greenish belts assistance power contamination by filtering aboveground runoff, trapping sediments, and reducing nutrients and toxins earlier they participate the water. They mitigate floods by absorbing storm-water surges, assistance successful groundwater recharge, and forestall ungraded erosion by stabilising banks. Additionally, buffer zones lend to microclimate regularisation by sequestering c and moderating section temperatures.

Scientific studies bespeak that the signifier and carnal features of buffer zones tin adjacent foretell which lakes oregon rivers are astatine hazard of nutrient overload, often starring to harmful algal growth.

A reappraisal of technological lit by this newsman revealed a important spread successful studies conducted successful India connected water buffer zones and their influencing factors. In contrast, Western countries person extensively studied however expanding and improving buffer zones lend to water wellness and trim sedimentation.

“Although sediment-trapping capacities are site- and vegetation-specific, and galore factors power sediment-trapping efficiency, the width of a buffer is important successful filtering cultivation runoff. Sediment-trapping ratio is affected by slope,” noted a insubstantial titled ‘A Review of Effectiveness of Vegetative Buffers connected Sediment Trapping successful Agricultural Areas’.

“Reviewing the narration betwixt sediment trapping and buffer width showed that wider buffers supply a longer residence clip for runoff h2o and are frankincense much effectual successful reducing sediment,” stated Major Factors Influencing the Efficacy of Vegetated Buffers connected Sediment Trapping.

In a survey titled ‘Tree-climbing Mangrove Crabs of Karwar, West Coast of India’, researcher Pradnya D. Bandekar collected samples from creeks, inlets, and the buffer zones oregon marginal strips of the Karwar coastline. This underscores the value of buffer zones, arsenic galore aquatic taxon trust connected these strips regularly.

Scientific perspectives

Priyanka Jamwal, elder fellow, Water and Society, explained, “The vegetation successful buffer zones serves respective important purposes. It enhances biodiversity by attracting birds and different taxon and helps chill the section microclimate. Research has shown that vegetated areas tin importantly little surrounding temperatures.”

“Buffer zones play a captious relation successful reducing non-point root pollution,” she added. “When rainwater flows into a water from aggregate directions, it passes done these vegetated buffers, which enactment arsenic earthy filters. Through biologic and chemic processes, they sorb nutrients and trap pollutants earlier the h2o enters the lake. Removing these buffer zones volition inevitably degrade h2o quality, truthful maintaining steadfast buffers astir lakes and streams is perfectly essential”.

Shivakumar Magada, prof of Aquatic Biology and limnologist, explained that erstwhile excess nutrients participate a water successful the lack of an extended buffer zone, it disrupts the water ecosystem, perchance sidesplitting aquatic life.

Regarding drains, Inayathulla M., prof and manager of the Water Institute astatine UVCE, said, “Urbanisation has importantly altered earthy drainage patterns, reducing the capableness of storm-water systems to grip floods. Reducing drain buffer zones volition person a akin effect.” He added that floods are already occurring successful the city, and the concern volition worsen if buffer zones are reduced.

“Even tiny modifications to drain systems tin change h2o volume, travel patterns, and semipermanent trends. Concrete surfaces astir buffer zones summation imperviousness, limiting infiltration and groundwater recharge,” helium explained. “Maintaining the earthy strategy is indispensable for sustainable flood and groundwater management”.

Veena Srinivasan, enforcement director, WELL Labs, noted that cities similar Bengaluru person already mislaid astir of their greenish cover, arsenic shown successful maps wherever areas that were erstwhile predominantly greenish are present marked red.

“Buffer zones astir lakes are among the past remaining greenish spaces successful the city, providing important habitats for birds and different species. When these zones are reduced, particularly crossed galore tiny lakes, we’re efficaciously cutting down trees, urbanising delicate areas, and further shrinking the city’s greenish infrastructure,” she added.

Tata Nagar: A lawsuit study

Tata Nagar successful bluish Bengaluru provides an illustration of these concerns.

Tata Nagar has experienced yearly flooding, chiefly owed to its topography, poorly planned storm-water drains, and deficiency of maintenance. Even during this reporter’s tract sojourn to Tata Nagar, Kodigehalli, Vidyaranyapura, and Bhadrappa Layout, it was observed that the storm-water drain infrastructure remains beneath standard.

The Master Plan of Bengaluru 2015 shows lone 1 large storm-water drain successful the area, whereas determination are really two, and 1 of them connects Doddabommasandra Lake and Hebbal Lake. The Tata Nagar drain connects to 1 of these large drains, which has been encroached upon by houses and flat complexes. In fact, 1 of the main roads is built straight implicit a stormwater drain. Over the years, aggregate non-natural drains person been constructed to code flooding successful Tata Nagar, but these person lone created choke points, exacerbating flooding some locally and elsewhere. Unfortunately, maps of these hasty drain connections are unavailable, and astir of these drains deficiency due endpoints.

These issues are besides highlighted successful the 2021 CAG report, which emphasises the substandard storm-water drain web successful the city. The study further notes that civic bodies specified arsenic BDA, BWSSB, and BBMP themselves person encroached upon storm-water drain networks.

Amidst these challenges, the World Bank is backing the Bengaluru Water Resilience Project, which aims to physique a robust storm-water drain web and mitigate floods. Implementing this project, however, volition beryllium analyzable if the buffer portion instrumentality is notified, arsenic determination volition beryllium nary mechanics to code historical encroachments.

Meanwhile, the authorities is pushing to walk the Bill. On Wednesday, Minister Boseraju affirmed that the buffer portion amendment was based connected a technological study, and the documents and clarifications requested by the Governor pursuing the ailment are being finalised and volition beryllium submitted soon.