What is the main objective of establishing clear 'trigger levels' for different flood warning stages (e.g., alert, warning, evacuation)?

The main objective of establishing clear 'trigger levels' for different flood warning stages is to provide a standardized, objective, and actionable framework for managing escalating flood risks, thereby ensuring a timely and effective response to protect lives and property. Trigger levels are pre-defined, measurable hydrological thresholds, such as specific river gauge heights in meters or cumulative rainfall amounts, that scientifically indicate when a particular flood warn....