Flood Mapping

Workflow Goal

Map likely flood extent for an event, compare it with normal surface-water conditions, and prepare outputs that support response, damage review, or recovery planning.

Outline

• Define the event dates, affected area, reporting units, and whether the focus is maximum extent or date-specific inundation.
• Collect suitable radar or optical imagery, permanent water references, elevation data, administrative boundaries, and infrastructure layers.
• Build event and baseline observations using comparable dates, then mask areas that commonly cause false detections.
• Identify likely inundation with water-sensitive thresholds, change detection, terrain constraints, or classification rules.
• Separate temporary flooding from permanent water, wet soil, shadows, vegetation effects, and radar artifacts.
• Summarize mapped flood extent by community, parcel, road segment, crop area, or watershed.
• Produce event maps, exposure tables, QA flags, and notes on data gaps caused by clouds, timing, or sensor limitations.

Later Examples

• Rapid flood extent mapping from radar imagery.
• Exposure summary for roads and critical facilities.
• Agricultural inundation assessment by field boundary.