Which practice directly helps minimize stagnation in a cold water distribution system?

• A. Shut off fixtures to prevent leaks.
• B. Keep the water surface level high.
• C. Regularly use fixtures and minimize dead legs.
• D. Install extra storage tanks.

Answer: (C)

Stagnation in a cold water system happens when water sits in pipes for extended periods, allowing disinfectant levels to drop and the water to quality to degrade. The most effective way to prevent this is to keep water moving by regularly using fixtures and by minimizing dead legs—short, unused runs of pipe where water can sit and age. Regularly drawing water through the system flushes fresh water into the pipes and helps maintain a protective disinfectant residual, while reducing dead legs eliminates areas where stagnant water can linger. Shutting off fixtures to prevent leaks reduces overall turnover, and adding extra storage tanks can create more long, unused runs rather than solutions to stagnation. So, using fixtures regularly and minimizing dead legs directly promotes continual turnover and better water quality.