A view of the Great Lakes from space
A view of the Great Lakes from space. In 1972, U.S. and Canada signed the Great Lakes Quality Agreement of 1972. The Agreement, first signed in 1972 and renewed in 1978, expresses the commitment of Canada and the U.S. to restore and maintain the chemical, physical and biological integrity of the Great Lakes Basin Ecosystem. It also reaffirms the rights and obligations of the two countries under the Boundary Waters Treaty.