The Ministry of Municipal and Rural Affairs and Housing in the Kingdom of Saudi Arabia sets strict health regulations and conditions to ensure the quality of drinking water in tanks. These standards include: Periodic Cleaning: It is recommended to clean overhead tanks every 4-6 months, while ground tanks may require less frequent cleaning but no less than once a year. Use of Safe Materials: Cleaning and disinfection materials that are approved and harmless to human health, such as chlorine at specific concentrations, must be used. Systematic Cleaning Steps: Specific steps must be followed to ensure thorough and effective cleaning. Disinfection After Cleaning: Disinfection is an essential step to eliminate any remaining bacteria or germs after the cleaning process. Importance of Periodic Tank Cleaning: Impurities and sediments accumulate inside tanks over time, especially in areas with high temperatures like Makkah Al-Mukarramah, where surface temperatures can reach 60°C, accelerating the growth of bacteria and fungi. This accumulation leads to: Water Contamination: The water becomes unfit for drinking and use, and may contain pathogens. Spread of Diseases: Intestinal and skin diseases can be transmitted as a result of using contaminated water. Change in Water Properties: The smell, taste, and color of the water are affected, making it unacceptable for use. Tank Damage: Sediments can cause corrosion of the tank walls and damage it in the long run.