In a house, water is needed for carrying out various activities. The system of drawing water from treatment plant and making it available at all appliances (fixtures) for use is known as domestic water supply system. As per the use, water supply system carries hot and cold water throughout the house. Pipes convey water from source to various appliances. The flow of water to appliances is controlled by valves and faucets (tap). The used water is conveyed to drain.
Based on the coming of water into the house, water supply system is of two types:
- Direct Water Supply system
- Indirect Water Supply system
01. Direct Water Supply System:
In direct water supply system all appliances in a house receives water from the rising main i.e of Municipal supply mains. Water available at all faucets is pressured potable water. No cistern is required to store water first and then making it available for use. Cistern (tank) is required only if hot water system is of storage type. Here also, the cistern stores only hot water. Cold water is from rising main. In order to install direct water supply system, rising main (Main pipe from where water enters house) should have sufficient pressure so that the water reaches fixtures without causing inconvenience in use of fixture even at upper storeys. As rising main pressure is high, a pressure reducing valve may be required to maintain required water flow. This system avoids contamination of water, caused by storing water in underground or overhead tank.
02. Indirect Water Supply System:
Water enters house from the rising main. After entering, it is branched off into kitchen sink and towards storage tank. Storage tank is first filled and then water is supplied to appliances from same. The location of storage tank should be at some height so that water flows down easily under gravity without any external pressure. Only Kitchen sink has portable water available. All other appliances have stored tank water. Indirect water supply system is flexible because when mains run out of water, stored water is a benefit till mains flow return.