Dirty Water With Foam Swiftly Flows From One Tank to Another, a Stage of Water Purification For Its Repeated Use, a Big Pool With Muddy Water, a Stream of Mud, Foam From the Formation of Gas, the Process of Decomposition of Bacteria, Fermentation in Water, Modern Methods of Cleaning. Process of Water Purification With the Formation of a Large Amount of Foam, Outdoor Pool on the Street, Red, Brown, Gray, Muddy, Dirty Water, Large Bubbles Burst, Gas Evolution, Bacterial Sediment, the Use of Filters of Different Degrees of Purification, the Requirements For Water Purification Standards, Drinking Water Quality in the Faucet, the Water Settles, the Modern Structure For Water Purification in the City, the System of Pipes and Pools