To estimate consumptive use, the states and provinces apply various consumptive use coefficients as summarized in the table below.

Developing more accurate consumptive use information is a regional priority. The following reports on consumptive use is available from U.S. Geological Survey Great Lakes Basin Pilot Publications page:

• Consumptive Water Use Coefficients for the Great Lakes Basin and Climatically Similar Areas
• Fact Sheet: Consumptive Water Use in the Great Lakes Basin
• Variations in Withdrawal, Return Flow and Consumptive Use of Water in Ohio and Indiana, with Selected Data from Wisconsin, 1999-2004