New Report: Heavy Rain Exacerbating Farm Runoff, Worsening Toxic Algae Blooms In Lake Erie

Global Warming, says report, will only make problem worse

04-29-2013 // Jordan Lubetkin

As the Great Lakes region experiences massive flooding due to weeks of heavy rain, a new report from the National Wildlife Federation examines how intense rain events are exacerbating farm runoff and contributing to record toxic algal blooms in Lake Erie that impact public health, drinking water supplies and wildlife. The report warns that the storms driving harmful algal blooms will only become more common due to global warming.

“Lake Erie is experiencing a one-two punch of heavy rains and farm run-off that is influencing the magnitude of toxic algal blooms,” said report author Melinda Koslow, regional program manager at the National Wildlife Federation’ Great Lakes Regional Center. “Global warming will only exacerbate this urgent problem. Thankfully, there are solutions to help farmers and communities protect our Lakes, environment and economy.”

Read the report at:

“Taken by Storm: How Heavy Rain is Worsening Algal Blooms in Lake Erie” looks at spring rainfall patterns in Ohio and finds that dry years such as 2012 deterred algae growth, while record-breaking rains such as those in 2011 led to historic toxic algal blooms in Lake Erie that covered over 3,000 square miles, could be seen from outer space on NASA photographs and contained toxicity levels more than 1,000 greater than those deemed safe by the World Health Organization.

“Spring rainfall drives summer algal blooms,” said Peter Richards, senior research scientist at the National Center for Water Quality Research at Heidelberg University. “Heavy rains flush farm fertilizers and manure into local waters which drain into Lake Erie, leading to excessive amounts of phosphorus, which fuel the explosive growth of algae.”

Harmful algal blooms can sicken or kill people and pets; harm wildlife; hurt outdoor recreational opportunities; and cost municipalities more money to treat drinking water.  Algal blooms and low-oxygen dead zones contributed to the near-death of Lake Erie in the 1960s. Due to landmark environmental legislation such as the Clean Water Act and an infusion of federal funding to help communities update sewers to better treat human waste and to prevent sewage overflows, algal blooms and dead zones subsided.

The resurgence of harmful blooms and the dead zone in the mid 1990s can be attributed to increasing amounts of dissolved reactive phosphorus entering Lake Erie through the Maumee River and other watersheds that drain to the Western and Central basins of Lake Erie in the United States and Canada. Scientists are concerned with the increasing amounts of dissolved reactive phosphorus in the water because it is more readily available for algae and can fuel rapid growth leading to algal blooms. Particulate phosphorus, on the other hand, tends to settle in stream and lake bottoms where it may no longer be available to algae.

“Taken by Storm” focuses on the Maumee River because it is the largest tributary and carrier of phosphorus into Lake Erie. Since 1995, the report notes, the amount of dissolved reactive phosphorus entering Lake Erie from the Maumee River has increased 218 percent.

“The Maumee River can be viewed as a surrogate for watersheds in the Great Lakes and across the country,” said Don Scavia, director of the Graham Environmental Sustainability Institute at the University of Michigan. “America’s great waters—from the Chesapeake Bay to the Gulf of Mexico—are grappling with expansive dead zones and toxic algal blooms. This is a serious problem that the country needs to confront.”

The report outlines a suite of solutions at the state, regional and national level to help implement strong farm conservation practices; restore the natural landscape and wetlands to reduce runoff; and reduce carbon pollution that causes global warming.