Lake Erie Water Quality

Lake Erie has often been held up as an environmental success story as corrective measures reduced phosphorus loading from the 1960s through the 1980s and transformed the shallowest of the Great Lakes from dead to alive and vibrant again. But then something happened – in 2011, Lake Erie experienced its worst algal bloom ever. The 2011 algal bloom was so large that it was visible from space.

Why had previous corrective measures worked so well for so long but now we seem to be back to square one?

IJC assessment of Lake Erie

Trying to figure out what happened is what the International Joint Commission (IJC) set out to do when they undertook their study. The resulting February 2014 report, “A Balanced Diet for Lake Erie, Reducing Phosphorus Loading and Harmful Algal Blooms,” points to some potential causes and offers some suggested remedies. For those in this watershed that may be identified as contributing sources of phosphorus, expect near term action plans to reduce phosphorus.

Source of phosphorus

So what is the source of this phosphorus loading? According to the report, “Agriculture operations are a major source of phosphorus loadings into Lake Erie. These loadings result primarily from fertilizer application and manure. The bulk of this input occurs during spring snowmelt and heavy rainstorms, when significant amounts of phosphorus can be transported by runoff water.”

While the report provides great detail about the various agricultural sources of phosphorus, they point specifically to the Maumee River (Ohio) watershed as an area of significance. But they mention a less well known source as well: the large concentration of greenhouses in Essex County (Ontario, Canada).  A 2011 study by the Ministry of the Environment concluded that many of the greenhouses discharge wastewater with high phosphorus concentrations into creeks that flow to Lake Erie.

This focus on watersheds, especially as it relates to agriculture, is a larger trend that we expect to continue in the coming years. This focus may consider the use of new best management practices and perhaps other incentive-based measures (as opposed to traditional “command and control” or regulatory).

Solutions must be based on science

Certainly, we support efforts to find a solution to issues of impaired watersheds. But we do so with this one caveat: make sure they are based on science rather than conjecture. What we know and what we think we know are not always the same. For example, in 1979, when Dr. Michael Sklash (Dragun senior hydrogeologist) published “The Role of Groundwater in Storm Runoff Generation,” most everyone was certain that groundwater played an insignificant role in storm runoff. They were wrong.

Then, and perhaps now, there are those that ignore how groundwater discharge plays a more significant role in surface water quality. And depending on the chemical, focusing on surface water may not lead to meaningful solutions.

Identifying the cause of the algal blooms in Lake Erie is very important, environmentally and economically. But let’s make sure we truly understand the causes before we start applying (practical) solutions.

To learn more about groundwater’s role in storm runoff, contact Dr. Michael Sklash at 248-932-0228. To read the IJC report click here.