The water distribution system must always be designed based on which of the following factors?

Designing a water distribution system is crucial to ensuring reliable and consistent water delivery to various fixtures and points of use within a building. The minimum pressure available is a critical factor in this design process because water must reach all fixtures effectively, and maintaining adequate pressure is essential for functionality.

If the minimum pressure available is not sufficient, it can lead to poor performance in fixture operation, such as low flow rates from faucets or inadequate flushing of toilets. Additionally, pressure affects the ability to deliver water to higher floors in multi-story buildings, making it vital to consider when planning the system.

While maximum flow, average water usage, and total fixture count are also important factors to consider in a well-rounded design, they do not directly ensure that all parts of the system will function correctly if the pressure constraints are not met. Therefore, understanding and designing around the minimum pressure available is fundamental to the success of the water distribution system.