On an annual basis, the Great Lakes Commission - the repository for the Great Lakes – St. Lawrence River Water Use Database - sends an e-mail request for the pervious year’s water use data in the fall to states and provinces. All data are submitted to the repository in a Microsoft Excel or Access format then compiled into a single Microsoft Access database. All data are in one of two unit measures—millions of . gallons per day (mgd) or millions of liters per day (mld)—and values are initially set to zero. Numeric values are required for all.
