This is a substantive shift in how India regulates land along its most important river, and it cuts both ways. The government's case is that a blanket prohibition covering the entire floodplain was legally inconsistent and practically unenforceable — settlements, farming and religious activity already exist across that land, and a rule nobody can apply protects nothing. Graded zoning, on this view, makes the strictest protection credible precisely by confining it to the land that genuinely floods often. The counter-concern is equally clear: replacing a prohibition with a clearance requirement moves the decision from a rule to a discretionary process, and floodplains that are built upon do not merely put buildings at risk — they remove the space a river needs to absorb a flood, pushing water elsewhere. For UPSC, the value of this story is that it is a live example of the trade-off between enforceable regulation and strong regulation.