2 WATER DISTRIBUTION.pdf

Lecture 2 WATER SUPPLY AND DISTRIBUTION SYSTEM Definition Carries water from the water source, street main or a pump to the building and to various points in the building at which water is used. COLD WATER SUPPLY HOT WATER SUPPLY WATER plays an important part in the plumbing system Providing water i...

Lecture 2 WATER SUPPLY AND DISTRIBUTION SYSTEM Definition Carries water from the water source, street main or a pump to the building and to various points in the building at which water is used. COLD WATER SUPPLY HOT WATER SUPPLY WATER plays an important part in the plumbing system Providing water is one of the most critical utility requirements “Universal Solvent” WATER CYCLE 3 MAJOR STAGES EVAPORATION CONDENSATION PRECIPITATION SOURCES OF WATER 1. RAIN WATER Collected from roofs of buildings and special water sheds and stored in cisterns or ponds. ADVANTAGE Water is soft & pure and is suitable for the hot water supply system DISADVANTAGE Only a source during the wet season Storage becomes a breeding place for mosquitoes Roofs may not be clean 2. GROUND WATER The portion of the rainwater which has percolated into the earth to form underground deposits called aquifers (water- bearing soil formation). ADVANTAGE DISADVANTAGE From springs and wells and is the principal source of water for domestic use in most rural areas. ADVANTAGE Usually has an abundant supply; requires less treatment because of natural filtering. DISADVANTAGE May have organic matter & chemical elements usually treatment is suggested. 3. NATURAL SURFACE WATER A mixture of surface run-off and ground water. Surface sources includes rivers, lakes, ponds and impounding reservoirs. ADVANTAGE Usually easy to acquire and in large quantities. Used for irrigation, industrial purposes and, when treated, for community water supply. DISADVANTAGE Contains a large amount of bacteria, organic, & inorganic substances; Purification & treatment is necessary USES OF WATER NOURISHMENT CLEANSING AND HYGIENE CEREMONIAL USES TRANSPORTATIONAL USES COOLING MEDIUM ORNAMENTAL ELEMENT PROTECTIVE USES PHYSICAL PROPERTIES OF WATER SURFACE TENSION- The ability to stick itself together and pull itself together HEAT ABSOPTION/CAPACITY - The ability to absorb heat without becoming warmer CAPILLARITY - The ability to climb up a surface against the pull of gravity DISSOLVING ABILITY - Known as the “Universal Solvent” Water treatment and purification is any method that will remove one or more materials that make the water unsuitable for a given use AERATION Water is sprayed into the air to release any trapped gases and absorb additional oxygen for better taste. COAGULATION – FLOCCULATION process by which small sediment particles which do not settle well combine together to form larger particles which can be removed by sedimentation COAGULATION chemical process in which the coagulant reacts with the sediment to make it capable of combining into larger particles. FLOCCULATION physical process in which the sediment particles collide with each other and stick together. SEDIMENTATION suspended solids are removed from the water by gravity settling and deposition water is passed through basins so sediments can settle through a period of time FILTRATION water is passed through layers of sand and gravel in concrete basins in order to remove the finer suspended particles. DISINFECTION/ CHLORINATION method of introducing a controlled amount of chlorine to the water in order to attain a desired degree of disinfection. THE WATER TREATMENT PROCESS