Water demand

1. Water demand

2. WATER DEMAND • Domestic demand This includes the water required in private building for drinking ,bathing, gardening, sanitary purpose, etc. As per IS : 200 l/c/d (with fully flushing system) 135 l/c/d (for weaker sections and LIG) • Public demand • it represents the water demand for public utility purpose. • like washing of public parks, gardening, washing on roads, public • fountain. 20 l/c/d • Industrial demand It represents the water demand of industries which are earlier existing or are likely to be started in future. As per IS : 50 l/c/d (for normal industries ) 450 l/c/d (industrial cities)

3. WATER DEMAND • Commercial demand Water requirement for institutions , hotels , schools, colleges, offices. As per IS : 20 l/c/d (for normal commercial area) 50 l/c/d (highly commercial area) • Fire demand • in populated or industrial area fires generally breakout and may lead to • serious problem. For control that situation require sufficient quantity • water that is called fire demand. • Water demand require for thefts and wastes This includes the water lost in leakage and stolen water due to unauthorised water connection.

4. Water requirement for different uses Domestic demand 135 l/c/d Public demand 20 l/c/d Industrial demand 50 l/c/d Commercial demand 20 l/c/d Fire demand 15 l/c/d Loss and waste 50 l/c/d 270 l/c/d

5. FACTORE AFFECTING THE WATER DEMAND • Size of the city Small towns Big city Example: Delhi 244 l/c/d Vijayawada 135 l/c/d • Climate condition less in winter more in summer • Cost of water demand rate rate demand

6. Distribution System demand demand Pressure high Pressure low • Supply system Good supply Bad Supply demand demand

7. Industry industry industry demand demand • Quality of water good bad demand demand • Habit of people (Living style) EWS demand MIG demand

8. Per Capita Demand The demand of water per person per day. yearly water demand per capita demand : • population x 365 An average Indian town per capita consumption varies from 150 to 300 liters.

9. Fire Fighting Required Calculation Total amount of water required : no. of fires X discharge X time of each fire Amount of water required per person: amount of water/total population Kuichling ‘s formula : Q= 3182√P [ Q = amount of water required in liters/minute] [ P = population in thousands] Freeman formula : Q= 1136[(P/10)+10 ] Buston’s formula : Q= 5,663√P (Quantity of water required in liters per day) (Kuichling formula, Freeman formula and buston formula give higher results. Because water for fire fighting is required for few times in a year.) Q = 100√P (water is kiloliter per day)

10. Fire Fighting Required Calculation • National board of fire under writers formulas : • When population is less than or equal to 2,00000 • Q= 4,637 √ P[1-0.01 √P ] • When the population more than 2,00000 a provision for 54,600 liters/minute may be made with an extra additional provision of 9,100 to 36,400 liters/minute for a second fire. • For a residential city • Small or low buildings = 2200 litres/minute • Larger or higher buildings = 4500 litres/minute. • High value residence ,apartments, tenements= 7650 to 13500 litres/minute