Which interval is a typical recommended maintenance frequency for cleaning and inspecting water storage tanks?

• A. Every year
• B. Every 3-5 years
• C. Every 10 years
• D. Never

Answer: (B)

Regular cleaning and inspection of potable water storage tanks helps control sediment buildup, biofilm, and corrosion, while also spotting any structural issues before they affect water quality. The typical interval of every 3 to 5 years reflects a practical balance between maintaining safe, high-quality water and managing costs and downtime. Cleaning more often, like every year, isn't usually necessary unless special conditions exist, and waiting as long as 10 years increases the risk of degraded water quality and more significant repairs. Actual frequency can vary based on tank type, materials, water chemistry, turnover rate, and past inspection findings. The maintenance process generally involves draining or isolating the tank, cleaning interior surfaces and removing sediment, inspecting coatings and gaskets, disinfecting, flushing, and then returning the tank to service.