Lake Huron remains healthy despite nearshore algal blooms and a reduction in offshore nutrients by invasive filter-feeding mussels.
Lake Huron continues to be a good source of high-quality drinking water. Toxic chemicals monitored in Lake Huron are assessed as Good and long-term trends indicate that concentrations are declining. Contaminant concentrations in fish filets also continue to decline or are remaining stable. Lake Huron fish continue to be a nutritious food source, although restrictions on consumption of certain species of fish continue to be advised.
Lake Huron’s beaches and nearshore waters are most often clear, clean and provide good opportunities for swimming and other recreational use. Nutrient concentrations are considered to be Fair with a Deteriorating trend over the long-term due to reduced offshore phosphorus levels. Cladophora levels are generally low in Lake Huron, although some areas of the lake are prone to nuisance algal growth issues such as the southern end of Georgian Bay and Saginaw Bay. The current status of harmful algal blooms in Lake Huron is Fair with an Unchanging trend, with most impairments occurring in Saginaw Bay.
Lake Huron coastal wetlands account for approximately 30% of the total wetland area for all five Great Lakes. Coastal wetland conditions range from Fair to Good, with those in the northern regions generally in better condition. Agricultural and land use stressors, such as run-off from farms and urban areas, are more common in the southern part of the basin and contribute to coastal wetland degradation. Populations of fish as well as lower food web organisms such as Diporeia have remained low in the offshore waters since the mid-2000s. These populations continue to decline. Fish populations in the nearshore waters, including Walleye, have not been significantly impacted by the changes in the lower food web. Walleye populations are assessed as Good and Unchanging. Lake Trout are in Fair condition and the trend is Improving with increasing natural recruitment. The impacts of aquatic invasive species, specifically the filter feeding quagga mussel, are generally assessed as Poor. Invasive species are the main cause of lower productivity in offshore waters and nuisance algae growth in some nearshore waters. The status of invasive Sea Lamprey is Fair with adult Sea Lamprey populations above target but Improving. Between-lake spread of aquatic non-native species is assessed as Poor, as eight new non-native species have spread into Lake Huron from other basins over the last decade.
Groundwater quality is assessed as Good based on nitrate and chloride concentrations. Land-based stressors, such as changing land cover from natural lands to developed or agricultural lands, continue to impact the Lake Huron basin. Shifts in long-term climate trends, such as increasing water temperatures and decreasing ice cover, may have ecosystem implications.