The Union government eased restrictions governing construction along the Ganga flood plain this week, paving the way for building projects in areas which are only subject to moderate or rare flooding. This has been done by revising the definition of a ‘flood plain’ and deleting a clause in the legislation that expressly prohibited construction, according to an August 10 gazette order from the National Mission for Clean Ganga (NMCG), affiliated to the Jal Shakti Ministry.

A senior government official told The Hindu that the amendments did not represent any “dilution of standards”, but rather, attempted to correct an inconsistency in the law.

The ₹30,000 crore Namami Ganga mission, part of the NDA government’s ambitious venture to stem pollution in the Ganga river and maintain its ecological health, sources its legal teeth from the River Ganga (Rejuvenation, Protection and Management) Authorities Order, 2016.

‘Construction-free zone’

That notification defines the Ganga ‘flood plain’ as “the area of the river or its tributaries which comes under water on either side of it due to floods corresponding to its greatest flow or with a flood of frequency once-in-a-hundred years.”

The 2016 order included a clause saying: “...the bank of River Ganga and its flood plain shall be a construction free Zone to reduce pollution sources, pressures and to maintain its natural ground water recharge functions…” Other clauses banned construction in the “active flood plain” of the Ganga, though there was no definition of what constituted “active.”

Stratified regulation

However, an amendment to the 2016 order, published on August 10, makes two crucial modifications. It removes the “no construction” clause. It also adopts a stratified definition of ‘flood plain’ based on flood frequency: an ‘active flood plain’, which is immediately along the channel that submerges at least once every five years; a middle ‘regulatory zone’, subject to moderate flooding every five to 25 years; and an outer ‘warning zone’ on the periphery that floods only during severe 25- to 100-year events.

While the new order does not grant blanket permission for development, it replaces the total ban on flood plain construction with a regulated, approval-based system. Strict building prohibitions are now confined exclusively to the ‘active flood plain’, with minor exceptions reserved for temporary setups like religious events.

Beyond that five-year flood line, construction in the ‘regulatory’ and ‘warning’ zones is now permissible, subject to official clearances. However, any project, from roads and bridges to riverfront infrastructure, must still secure prior approval from the NMCG and regional authorities, while adhering to baseline environmental safeguards.

‘No dilution’

A senior government official told The Hindu that the intention behind the amendment was to remove a long-standing inconsistency. The 2016 order had used the term ‘active’ floodplain without defining it. “This wasn’t a problem initially but in the last few years there was feedback from several quarters that this was an inconsistency. The Central Water Commission released guidelines in July 2025 defining active, regulatory and warning zones for floodplains. In India, no State has clearly defined ‘flood plain’ zones. The August amendments now make the notification consistent. There is no dilution of standards at all,” said the official, who did not wish to be named.

In recent months, there have been several petitions before the National Green Tribunal (NGT) against construction along the Ganga and its tributaries, most recently the Gomti in Uttar Pradesh. Litigants have routinely cited the blanket “construction-free zone” mandate in the 2016 order in their petitions against riverfront roads and embankments, as well as in earlier cases involving municipal sewage treatment plants and riverfront works. The Hindu has reached out to the NMCG for clarification.

Published - August 11, 2026 08:08 pm IST