How are depth-damage curves and exposure maps used together in risk estimation?

• A. Exposure maps locate assets; depth-damage curves estimate expected damage given flood depth; combined to estimate total risk.
• B. They are interchangeable and redundant.
• C. Depth-damage curves only apply to environmental risk, not monetary.
• D. Exposure maps measure flood depth directly.

Answer: (A)

The main idea is turning a physical flood hazard into a monetary risk by linking asset locations to how badly they would be damaged. Exposure maps show where assets are and often their value, so you know what could be affected. Depth-damage curves describe, for each asset type, how much damage to expect as flood depth increases. When you overlay flood depth information onto the exposure map, you assign a depth to every asset and then apply that asset’s depth-damage curve to estimate its expected monetary damage. Adding up all those damages across assets gives the total risk for that flooding scenario and helps compare risks across scenarios or prioritize protections.

Think of it this way: exposure maps tell you what’s at stake and where, while depth-damage curves translate a flood depth into cost for each asset. They aren’t interchangeable—exposure maps don’t measure flood depth themselves, and depth-damage curves aren’t about identifying asset locations.