What is the main reason for preventing a direct connection between a potable water pipe and a wastewater pump?

The primary concern with preventing a direct connection between a potable water pipe and a wastewater pump is to avoid cross-connection. A cross-connection occurs when there is a physical connection between a potable (drinking) water system and a non-potable (wastewater) system. This type of connection can lead to contamination of the potable water supply if wastewater backs up into the drinking water system, posing significant health risks to the public.

Keeping these systems separate ensures that there is no possibility for contaminants to flow back into the clean water supply, thus protecting public health and safety. Proper plumbing practices, including the use of backflow prevention devices, are critical in maintaining this separation and preventing cross-connection.

The other options, while related to water system integrity, do not directly address the critical public health issue of contamination that a cross-connection poses.