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 litre per capita per day (/pcd).
  • Under ordinary condition (as per I.S. code) the minimum domestic water demand for a town or a city with full flushing system Should be taken at 200 lpcd. Although it can be reduced to 135 lpcd  for economical weaker section and LIG colonies depending upon prevailing conditions.

1. Minimum domestic water consumption (Annual average) for Indian town and cities with Full Flushing  systems as per 1172-1993.

water demand

2. Minimum domestic water consumption (Annual average) for weaker section and LIG (Lower Income Group) Colonies in small Indian Towns and Cities.

water demand tutorials tips


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 member in a Day  = 675 lit.

Assume the water consumption 1000 lit.

We know water density is 1000 lit/m3

1m3 = 1000 lit.

Water tank volume is  = 1m3



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 water tank and cross section of water tank


Excel Sheet For Size Calculation –excel sheet

water tank design


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4 Responses

  1. vivek kumar Gupta says:

    Indeed a very good teaching on Water Tank Calculation. You have made all points cleared here.

    I had only one doubt, i.e on your excel sheet when we putting Quantity of Volume its is showing such a 3K + KG of Cement for Tank Size of L= 3 mtr, W= 3 mtr and H= 1.5 mtr
    and Bottom Ramp of 3.5 * 3.5 * .02 (L*B*H) (ALL IN METER)

    Pls take a look, i would be thankful to you.

  2. Azmeraw says:

    Very important site!!

  3. Tauseef says:

    how to calculate steel bar in water tank

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