Grand Traverse Bay is one of the few remaining oligotrophic embayments in the Great Lakes and arguably has the highest water quality of the larger Lake Michigan bays. Oligotrophic is a term applied to lakes that are typically low in accumulated nutrients and high in dissolved oxygen, both of which are characteristics of high quality waters. Lakes such as these are clear and blue and most often cold, like Grand Traverse Bay.

Overall, the prevailing opinion among experts is that water quality in Grand Traverse Bay is excellent, but there are several potential threats to that quality. Excessive nutrients and toxic contaminants from runoff are just two examples of potential threats to the bay. For the most part however, Grand Traverse Bay is typical of other oligotrophic embayments in the Great Lakes; deep, clear, cold, with an overall low productivity.

A summary of specific water quality parameters for Grand Traverse Bay can be found in Section 3.11 of the Grand Traverse Bay Watershed Protection Plan. More information regarding water quality and pollutants to Grand Traverse Bay and its watershed can be found in the Designated Uses, Pollutants and Sources, and Priority Areas sections of our website.