The Great Lakes-St. Lawrence Basin has been the focus of a number of studies relating to future climate change, which is expected to affect the water quality and ecology (primary productivity, species diversity, food web dynamics) of the Basin. While the changes are anticipated to be felt basin-wide, the most pronounced effects are likely in tributary streams, bays, near-shore shallows and the central basin of Lake Erie. This could have serious implications for water quality and aquatic biota. Lower lake levels are expected in all lakes, with Lakes Erie and Ontario experiencing reductions of one meter or more. This has implications for hydropower, shipping, salt water intrusion in the St Lawrence River and it raises questions about future policy decisions on water withdrawals and regulation of lake levels.
Eighty percent of China's major rivers are so degraded they no longer support fish.