Water Quality Objectives for the Great Lakes

The United States and Canada signed the Great Lakes Water Quality Agreement in 1972 and renegotiated and strengthened it in 1978. In order to establish criteria for protection and against which to measure water quality status, the Agreement calls for the development of objectives for potentially polluting substances and effects. To develop these objectives, a set of guidelines were developed. The most important of these are: 1) the objectives are intended to protect all beneficial uses of the Great Lakes; 2) they are set at the level of no detectable effect; 3) uncertainties concerning their development are always resolved in favor of protection; 4) all objectives must be scientifically defensible; 5) they are not necessarily practical for direct implementation as regulatory standards; 6) they are not intended to protect all beneficial uses under any conditions; and 7) they are intended to be subject to periodic review.