What designation on an old format FIRM corresponds to Zone C on the newer format FIRM?

The designation on an old format Flood Insurance Rate Map (FIRM) that corresponds to Zone C on the newer format FIRM is Zone X. This is because Zone C was previously used to identify areas of minimal flood risk, which are now included in Zone X, reflecting areas outside of the Special Flood Hazard Areas (SFHAs).

Zone X encompasses areas that are determined to be at a lower risk of flooding, such as areas that are protected from the 100-year flood by levees or those where the annual chance of flooding is less than one percent. This transition in designations helps to maintain clarity and consistency in floodplain management, ensuring that stakeholders understand risk levels associated with different geographical areas.

In contrast, the other designations listed do not correspond to the risk category represented by Zone C. Zone A represents areas subject to inundation by the 100-year flood and does not match the low-risk designation of Zone C. Zone B typically refers to the area between the limits of the 100-year and 500-year floods, which again does not directly align with the minimal risk classification. Zone D indicates areas of undetermined flood hazards, which further distinguishes it from the characteristics of Zone C. Therefore, the choice of Zone X accurately reflects