Coastal and Floodplain Construction Inspector's Practice Exam

The design flood elevation in Zone AO is determined by what?

1. The average height of the structure

2. The highest existing grade plus the depth specified

3. The lowest point of the property

4. The average annual precipitation levels

The correct answer is: The highest existing grade plus the depth specified

The design flood elevation in Zone AO is determined by the highest existing grade plus the depth specified, which reflects the nature of flood hazard in this specific zone. Zone AO is characterized by areas subject to inundation by one or more flood events with a depth of flooding that varies. The flood depth is typically established based on historical data and FEMA regulations for the specific area. By taking the highest existing grade, which is the highest point in the surrounding area before any proposed construction or land alteration, and adding the specified flood depth, the design flood elevation ensures that the structure will be elevated above the anticipated flood levels and thus provide adequate protection against potential flooding. This approach is critical in ensuring that new structures are built in a safe manner that minimizes the risk of damage from flooding. The other options do not relate to the determination of design flood elevation in Zone AO. For instance, the average height of the structure does not account for potential flood levels, the lowest point of the property does not consider the existing grade where water may come from, and average annual precipitation levels do not directly correlate with flood elevation requirements, as they do not provide specific information about flooding potential in a given area.