WATER DEMAND AND WATER TANK SIZE & VOLUME CALCULATION
Domestic Water Demand
- The total domestic water consumption usually amounts to 50 to 60% of the total water consumption.
- The I.S. Code lays down a limit of water consumption between 135 to 225 litres per capita per day (/pcd).
- Under ordinary conditions (as per I.S. code) the minimum domestic water demand for a town or a city with a full flushing system Should be taken at 200 lpcd. Although it can be reduced to 135 lpcd for economically weaker sections and LIG colonies depending upon prevailing conditions.
1. Minimum domestic water consumption (Annual average) for Indian towns and cities with Full Flushing systems as per 1172-1993.
2. Minimum domestic water consumption (Annual average) for weaker sections and LIG (Lower Income Group) Colonies in small Indian Towns and Cities.
WATER TANK CAPACITY CALCULATION
For a Small LIG (Lower Income Group) family = 5 Members
Water Consumption in 1 Day = 135 litre
For 5 member in a Day = 135 x 5
For 5 members in a Day = 675 lit.
Assume the water consumption of 1000 lit.
We know water density is 1000 lit/m3
1m3 = 1000 lit.
Water tank volume is = 1m3
WATER TANK SIZE CALCULATION
Water tank volume is = 1m3
Volume of water tank is DxBxL
Assume water tank depth as your required = 0.5m
Depth is water tank is, D= 0.5 m
Area of water tank = 1/0.5 = 2
Area of water tank, L x B = 2 meter squre
Suppose L= 2B
2B X B = 2
B^2 = 2/2
B^2 =1
B = √1
B = 1
Width of water tank is, B= 1 m
Put value of B in assume equation, Suppose L= 2B
L = 2X1
L = 2
Length of water tank is, L = 2 m
Overall water tank site is DxBxL
0.5x1x2 = 1 meter cube
Here is a plan of the water tank and cross-section of the water tank
Excel Sheet For Size Calculation –
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