A residence using both potable and grey water systems must provide which of the following?

In a residence that utilizes both potable and grey water systems, it is essential to identify the nonpotable water system to ensure safety and compliance with health regulations. This identification prevents cross-contamination, helps users understand which water is safe for consumption and which is not, and guides proper use of each system.

By clearly marking nonpotable water systems, potential hazards are minimized, and individuals are informed about the proper handling and usage of grey water. This is particularly important in areas where grey water may be reused for irrigation or other non-consumptive purposes, distinguishing it from potable water which is intended for drinking and cooking.

While the other options may seem relevant, they do not hold the same critical importance for safety and regulatory compliance. Color-coded faucets could aid in identification but are not a standardized requirement. Separate plumbing permits are generally not necessary as long as the system complies with local building codes. Lastly, while periodic inspection reports are important for overall system maintenance, they do not directly address the immediate necessity of identifying the nonpotable system to prevent health risks.