India, Sept. 6 -- Two years after the Yamuna breached danger marks and inundated central Delhi in one of the worst floods in decades, the city has scrambled to plug the gaps that left it vulnerable in 2023. Dysfunctional gates have been repaired, embankments raised, and regulators reinforced as part of a shift from reactive firefighting to anticipatory flood management.

The urgency stems from history. The last comparable crisis came in 1978, when floodwaters devastated vast parts of the Capital. That disaster spurred Delhi to build stronger embankments, regulators, and bunds, which for decades kept major floods at bay. But experts said the 2023 floods exposed how both complacency and poor planning undid those gains.

Since 2023, the Delh...