In 1972, United States and Canada signed the first Great Lakes Water Quality Agreement (GLWQA). In September 7, 2013, forty years later GLWQA-4, was signed by Canada and the United States.

This new Agreement places an emphasis on studying aquatic ecology to develop solutions to problems of aquatic invasive species and habitat protection. The Agreement also comments on the impact climate change has on the Great Lakes.

Some environmental activists are critical of the GLWQA-4 as being a belated recognition of climate change, that is too soft on detailing the impact of climate change on the hydrogeology of Great Lakes. They believe GLWQA-4 fails to contain sufficient remedial measures and lacks specific goals to combat changing environmental conditions. By contrast prior versions of the Agreement set very specific objectives and measurable goals such as establishing unacceptable concentration levels for mercury, lead and certain pesticides in the lakes.

Proponents of this environmental accord argue that it is an appropriate response to tackling the problems of; invasive species, pollution and climate change. They specifically point to a positive history of improving lake conditions. For example, when GLWQA was initially signed forty years ago, Lake Erie was in a significant state of decline but the lake has vastly improved, which means a reduction in phosphorous levels in Lake Erie.

These bi-national efforts to protect the chemical, physical and biological integrity of the waters of the Great Lakes are overseen by the International Joint Commission (IJC) which advises the U.S. EPA and Environment Canada on establishing policy, science and action. The International Joint Commission shares information and assess progress on their priority issues of protecting nearshore environment, aquatic invasive species, habitat degradation and impact of climate change. These priorities are the focus of IJC’s continuing efforts to limit threats to public health and the environment in the Great Lakes Basin from harmful algae, toxic chemicals and discharges from vessels. Lake conditions will continue to be monitored and studied with progress reports made public every three years, at the direction of the IJC.