Calculators

Water Balance Program

Variable Definitions:

A: Input is Process/Facility Water Supply

B: Water Losses (e.g.; to air, land, and product)

C: Output is Wastewater Discharge

Input A:	Losses B:	Output C:

Water Supply Input

Purchased Water:
Groundwater (Private Wells):
Surface Water:
Captured Water:
Site Level Recycle/Reuse:
Seawater/Brackish:
Steam/Condensate:

Water Process Losses

Cooling Tower Evaporation:
Irrigation:
Boiler Steam:
Leaks:
Retained in Product (Beneficial Consumption):
Consumed in Reaction:
Treatment System Reject (Reverse Osmosis, Retained in Sludge):

Wastewater Discharge

Sanitary:
Process #1 Wastewater:
Process #2 Wastewater:
Process #3 Wastewater:
Cooling Tower Returns:
Metered:

Acceptable margin of error versus additional due diligence

Acceptable margin of error guidance

Water Balance Value:

Margin of Error:

Percent Closure Result:

An acceptable margin of error should be 10 percent or less. The margin of error is calculated by dividing the water balance value found in column B above by the total water input value. If the water balance value is over 20 percent, then the user is encouraged to perform additional investigaton and dig deeper.

The following provides suggested guidance based on volume of water used:

Range 0 to 10,000 gallons (15% acceptable margin of error)
Range 10,000 to 100,000 gallons (10% acceptable margin of error)
Range 100,000 to 1,000,000 gallons (5% acceptable margin of error)
Range greater than 1,000,000 gallons (1 to 2%)

Other Helpful Calculators

To print this calculator or to use it as a standalone file, please download the Excel format below. (Right-click on the link and select "Save Target As" to download it to your computer.)

Download Excel format

GEMI
1155 Fifteenth Street, NW,
Suite 500
Washington, DC 20005
Phone: 202-296-7449
Fax: 202-296-7442
info@gemi.org