PATNA, Sept. 13 -- Even as floodwaters begin their gradual retreat across parts of flood-ravaged Bihar, a perilous new threat has emerged along the state's river corridors. The Water Resources Department has issued a critical alert urging heightened vigilance following a sharp decline in river levels. Engineers warn that this sudden drawdown severely amplifies pore-water pressure inside waterlogged riverbanks. Stripped of the stabilizing hydrostatic counterweight of the floodwaters, saturated soil faces abrupt structural failure and acute bank subsidence, imperiling vital flood-protection embankments and adjoining settlements. In response to the escalating Sudden Drawdown Condition, field engineers and monitoring teams have been ordered to institute round-the-clock patrolling across all fragile, erosion-prone, and historically compromised sectors. Field units are vigilantly tracking altered river currents and structural fissures to catch early signs of collapse. To avert breaches, the department has mandated the pre-emptive staging of heavy machinery, emergency labor, and protective flood-fighting assets, directing teams to execute boulder dumping and geo-bag reinforcements immediately upon detecting destabilization. Local populations living along sensitive river stretches are being actively sensitised to the ongoing danger. The alert coincides with early signs of stabilisation across major river basins, offering a cautious glimmer of hope after weeks of severe inundation. The state Disaster Management Department reported receding levels in the Ganga at Sultanganj in Bhagalpur and the Sone at Indrapuri Barrage, while the Kosi at Birpur Barrage and the Gandak at Valmikinagar Barrage have stabilised. Despite these marginal drops, critical stretches along the Ganga, Gandak, and Kosi persist above danger marks at several key gauging stations. The deluge continues to strain 47.92 lakh residents across 574 village panchayats in 15 districts, with Patna, Bhagalpur, Bhojpur, and Saran bearing the brunt. Relief operations remain mobilized on a war footing. Over 1,248 operational community kitchens have dispatched more than 73.30 lakh hot meals, while 13 relief camps provide shelter, rations, and healthcare to 12,260 displaced citizens. Rescue operations are backed by 1,840 government boats alongside 37 deployed teams of the NDRF and SDRF distributing relief packets, tarpaulins, and livestock fodder. In Patna district, District Magistrate Kundan Kumar has enforced a strict zero-tolerance mandate against administrative delays, ensuring swift aid delivery, veterinary services, and transit assistance. Concurrently, medical teams have ramped up interventions across receding pockets to prevent water-borne disease outbreaks, deploying healthcare workers to promote sanitation, hygiene, and clean drinking water while monitoring riverbanks for unexpected structural failures....