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All Topics | Topic "Calculation of Domestic Water Consumption."
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Author Message
Ms. Humaira Abid

Subject: Calculation of Domestic Water Consumption.   
Posted: 5/8/2024 Viewed: 817 times
Can someone explain how to calculate annual water use rate and consumption for domestic demand, and what data will be needed for this?
Mr. Doug Chalmers

Subject: Re: Calculation of Domestic Water Consumption.   
Posted: 5/28/2024 Viewed: 337 times

I should note that there are two ways to input the demand into WEAP. The first is using the Annual Water Use Rate, Annual Activity Level, and Monthly Variation. Under this method, for domestic demands, you would likely enter the population under the Annual Activity Level and the water use rate per capita (ie. m3/person/year) under the Water Use Rate and the % of the annual amount used in each month under Monthly Variation (assuming your model is a monthly model), where you can specify if the water use is constant throughout the year, or perhaps higher in the summer and lower in the winter. The other method for inputting demands is to input the demand
during timestep directly into WEAP by going to the Data Tree --> Advanced --> Specify Monthly/Daily demand (note- you may have to enter a unit first in the Annual Activity Level to get this option to appear under advanced).

The consumption value represents the amount of water consumed and eliminated from the system, not returning to the river, or to the river via a WWTP system. For example, domestic water used in a kitchen or bathroom which returns to a WWTP without any loss would not have any water consumed while water used to irrigate a garden and lost to ET would be totally consumed.

The values which you should enter for these variables should come from literature studying your particular basin.

Hope this helps! Please let me know if you have further questions.
Topic "Calculation of Domestic Water Consumption."