If an area is prone to flooding, how high must intakes be positioned?

Intake positioning in an area prone to flooding is crucial to prevent water infiltration and ensure the system operates effectively during adverse weather conditions. The correct answer indicates that intakes must be located at or above the design flood level. This is essential because it helps to avoid the risk of contamination from floodwaters, which can lead to significant operational issues and health hazards.

Placing intakes at this height means they will remain above any anticipated floodwaters, providing a protective measure for the HVAC systems. Additionally, local building codes and regulations typically specify that mechanical equipment should be elevated to prevent water damage, align with safety standards, and ensure longevity of the systems.

Other options, such as positioning intakes at ground level or below the design flood level, directly expose them to the risk of flooding, making them likely to fail during heavy rains or storm surges. Elevating intakes to 20 feet above ground level is excessive and not practical unless specific unique local conditions dictate such a height, which isn’t commonly required or feasible for standard installations. Thus, securing the intakes at or above the design flood level strikes a balance between safety and practicality.