LECTURE NOTES PREPARED BY D.ASHOK KUMAR, M.Tech GKMCET Page1 UNIT 1 - PLANNING FOR WATER SUPPLY SYSTEM Public water supply system The primary objective of water treatment for public supply is to take the water from source , treat the water which are free from unpleasant taste and odour. Municipal water systems consist of the following units. 1. Collection works. 2. Transmission works. 3. Purification works. 4. Distribution works.

1.Collection works Collection works are meant for the development of surface water or ground water resources. 2. Transmission works These form the connecting link between the collection works and the purification works. 3. Purification works Filtration plants to remove objectionable colour, turbidity, bacteria and other harmful organisms. Deferrization and demanganization plants to remove excessive amounts of scale forming, soap consuming ingredients like calcium and magnesium ions. Softening plants to remove excessive amounts of scale forming, soap consuming ingredients like calcium and magnesium ions.

4. Distribution Works There are two patterns of water distribution Branching pattern with dead ends. Grid iron pattern. LECTURE NOTES PREPARED BY D.ASHOK KUMAR, M.Tech GKMCET Page2 Design period & population forecasting. Design period Generally ,water supply projects are designed for a design period of 20 40 years, after the completion. The time lay between the design and completion should not be more than 2 years.

Design period for project components Component Design period (Years)

1. Storage by dams 50

2. Infiltrations works 30

3.Pump sets (i) All prime movers except electric motors (ii) Electric motors and pumps 30 15

4.water treatments units 15

5.pipe connections to the several treatment units and other small appurtenances 30

6. Raw water and clear water converging mains 30

7. Clear water reservoirs at the head works, balancing tanks and service reservoirs. 15

8. Distribution system 30