The Not-So-Great Lakes: Diseases Still A Problem In Great Lakes
November - December 2008
This is the last in a five-article series on problems in the Great Lakes.
In 1885, a big rainstorm washed huge amounts of Chicago’s stockyard waste and sewage into Lake Michigan—the city’s drinking water source. A typhoid epidemic resulted that killed more than 75,000 people and led to construction of the Chicago Canal. That engineering marvel reversed the river’s flow and took the city’s sewage and livestock waste to the west. A big improvement—unless you happened to live west of Chicago along the Mississippi River system.
Since that health disaster in Chicago, billions have been spent on sewage treatment systems and such massive human disease outbreaks are a thing of the past. But we still load the Great Lakes with human and animal waste when big storms overwhelm combined sewer and stormwater systems, or when pipes break. We still have to close beaches every summer because of the risk of water-borne pathogens, and diseases of Great Lakes wildlife and fish are emerging issues.
Overflows, Bacteria, and Beach Closings
In mid-September of this year, a record rainfall including 6.6 inches of rain on September 13th, filled Chicago’s deep tunnels, surface reservoirs, and waterways. That prompted Metropolitan Water Reclamation District officials to open emergency floodgates and discharge up to 99 billion gallons of storm water and diluted sewage into Lake Michigan. It was the most wastewater to flow into the lake, the drinking water source for 10 million people, since 1985, when Chicago opened the first section of a 109-mile long network of storage tunnels.
Last year, the City of Detroit dumped 23 billion gallons of raw or inadequately treated sewage during combined sewer overflows. Less massive but troublesome overflows also occurred at other cities along the Great Lakes. In August of this year, three beaches—including one at the Bay City State Recreation Area—were closed in Bay County due to high bacteria levels. No one seemed sure where the E. coli bacteria—which come from the guts of animals—originated, but experts found enterococus bacteria and DNA evidence of human waste in beach muck. Failing septic systems, combined sewer overflows, and/or inadequately treated wastewater were all considered possible sources.
In 2007 in Grand Traverse Bay, high bacteria counts prompted health officials to close some beaches and issue broader advisories against swimming. On Lake St. Clair, the Metropolitan and Memorial Beaches in Macomb County were added to the Michigan Department of Environmental Quality’s list of impaired waters because of their long history of frequent beach closings. A recent study by a Grand Valley State University suggested that E. coli can “get trapped” in certain types of algae such as Cladophora and then become concentrated where waves wash up the algae. This all makes shoreline owners and beach-goers nervous because health and water quality officials don’t seem to have a firm handle on where or how much bacteria is likely to show up.
MDEQ is trying to address the problem by using federal funds provided by the Beaches Environmental Assessment and Coastal Health Act for increased monitoring of 594 beaches along 542 miles of Great Lakes shoreline. In the last three years, local health departments have received almost $1 million to monitor 200 “high priority” beaches. The data are made available on the MDEQ’s Beach Monitoring website, along with results of “WaterWatch,” a survey that seeks data on self-reported illnesses believed to be associated with exposure to water or muck. The fact that such programs are necessary to reduce public exposure is testimony that we still have a way to go in reducing water-borne pathogens in the Great Lakes.
Type E Botulism
In late summer and fall of 2006, thousands of fish-eating birds washed up on stretches of the northern shorelines of Lakes Michigan and Huron. The extensive die-offs were particularly evident at the Sleeping Bear Dunes National Lakeshore where the carcasses of about 3,000 gulls, cormorants, grebes, mergansers, loons and white-winged scoters (a species of diving duck) littered more than 10 miles of Lake Michigan beach. Smaller numbers of dead birds were scattered elsewhere, including Delta and Schoolcraft Counties in the Upper Peninsula. In 2007 much greater numbers of water birds (40% of which were loons) were killed on the Upper Peninsula’s Lake Michigan shore. The cause was Type E botulism, a finding not totally unexpected since up to 25,000 birds had been dying of the disease annually in Lakes Erie, Huron and Ontario since 1999.
While government studies to determine causes were underway, birds kept dying. This past July, dead gulls and cormorants were found along Lake Michigan beaches at Ludington State Park, providing evidence that the disease was spreading.
Scientists have recently found that exotic species play a role in this alarming spread of Type E botulism. Zebra and quagga mussels—brought to Michigan in the ballast water of ocean-going ships—are filtering planktonic algae and nutrients, increasing water clarity, and concentrating toxins of Clostridium botulisum bacteria. When the water is warmest, huge colonies of zebra and quagga mussels and growth of Cladophera (favored by increased light penetration to the lake bottom) combine to create nutrient-rich, low-oxygen zones on the lake bottoms. Amongst the rotting carcasses of the exotic mussels and algae, the bacteria population booms. Parts of the ecological mess are fed on by an invasive, exotic fish species—the round goby. Finally, birds eat gobies or the mussels, get sick and die, and are in turn eaten by other scavengers.
Viral Hemorrhagic Septicemia
A new fish-killing virus arrived in the Great Lakes around 2002. Within three years, viral hemorrhagic septicemia (VHS) began killing huge numbers of fish from lower Lake Huron all the way to the St. Lawrence River. Some fish losses to VHS also occurred in northern Lake Huron. Since 2007, VHS outbreaks in fish have occurred in parts of Lake Michigan as well.
We know that VHS causes fish to bleed to death, usually from their eyes, and that the invasive exotic virus is a mutant strain of a saltwater virus found in fish off the coast of the Maritime Provinces in Canada. We know VHS came to us the same way as zebra and quagga mussels, gobies, and a host of other pests—from ship ballast water. What we don’t know is what to do about it. Monitoring indicates the distribution of VHS is still spotty. But it is expected to begin moving up Michigan rivers.
Biologists hope to slow its spread by disinfecting fish eggs at hatcheries as they did to curb bacterial kidney disease in the late 1980s and early 90s. But many have given up hope of keeping it out of all five Great Lakes.
SERIES SUMMARY
The federal government, the Council of Great Lakes Governors, each bordering state, and just about every politician around have all committed to protecting and restoring the Great Lakes. Many have called for a coordinated effort. But the solutions are complicated and difficult, and there is still no common vision or universally supported agenda.
We have made great strides during the past 50 years in reducing most pollutants, but areas of concerns remain. Many of the toxic substances of great concern are dropping into the Great Lakes from the atmosphere, and limiting those substances would require an international effort. Public health threats have been identified and reduced, but too many beaches are still being closed because of bacteria levels. Variability associated with climate cycles and trends, water temperatures, and lake levels make monitoring and predictions extremely difficult.
It is tempting to simply call for a lot more government spending to dredge harbor sediments, regulate outflows of toxic materials, overhaul combined sewer systems, and improve the quality of storm water runoff. But a lot more traditional spending for water quality improvement is likely to yield only marginal results in the Great Lakes in the future. And with money expected to be scarce in the next few decades, we might do more good by stopping the introduction of exotics, and by pulling out all stops to limit those already in Michigan waters, than any other actions. The challenge is to allocate resources optimally. That will require maintaining end-of-the pipe controls, but also emphasizing bold new approaches to restoring this precious international resource.
Dr. Patrick J. Rusz
Director of Wildlife Programs
This is the last in a five-article series on problems in the Great Lakes.
In 1885, a big rainstorm washed huge amounts of Chicago’s stockyard waste and sewage into Lake Michigan—the city’s drinking water source. A typhoid epidemic resulted that killed more than 75,000 people and led to construction of the Chicago Canal. That engineering marvel reversed the river’s flow and took the city’s sewage and livestock waste to the west. A big improvement—unless you happened to live west of Chicago along the Mississippi River system.
Since that health disaster in Chicago, billions have been spent on sewage treatment systems and such massive human disease outbreaks are a thing of the past. But we still load the Great Lakes with human and animal waste when big storms overwhelm combined sewer and stormwater systems, or when pipes break. We still have to close beaches every summer because of the risk of water-borne pathogens, and diseases of Great Lakes wildlife and fish are emerging issues.
Overflows, Bacteria, and Beach Closings
In mid-September of this year, a record rainfall including 6.6 inches of rain on September 13th, filled Chicago’s deep tunnels, surface reservoirs, and waterways. That prompted Metropolitan Water Reclamation District officials to open emergency floodgates and discharge up to 99 billion gallons of storm water and diluted sewage into Lake Michigan. It was the most wastewater to flow into the lake, the drinking water source for 10 million people, since 1985, when Chicago opened the first section of a 109-mile long network of storage tunnels.
Last year, the City of Detroit dumped 23 billion gallons of raw or inadequately treated sewage during combined sewer overflows. Less massive but troublesome overflows also occurred at other cities along the Great Lakes. In August of this year, three beaches—including one at the Bay City State Recreation Area—were closed in Bay County due to high bacteria levels. No one seemed sure where the E. coli bacteria—which come from the guts of animals—originated, but experts found enterococus bacteria and DNA evidence of human waste in beach muck. Failing septic systems, combined sewer overflows, and/or inadequately treated wastewater were all considered possible sources.
In 2007 in Grand Traverse Bay, high bacteria counts prompted health officials to close some beaches and issue broader advisories against swimming. On Lake St. Clair, the Metropolitan and Memorial Beaches in Macomb County were added to the Michigan Department of Environmental Quality’s list of impaired waters because of their long history of frequent beach closings. A recent study by a Grand Valley State University suggested that E. coli can “get trapped” in certain types of algae such as Cladophora and then become concentrated where waves wash up the algae. This all makes shoreline owners and beach-goers nervous because health and water quality officials don’t seem to have a firm handle on where or how much bacteria is likely to show up.
MDEQ is trying to address the problem by using federal funds provided by the Beaches Environmental Assessment and Coastal Health Act for increased monitoring of 594 beaches along 542 miles of Great Lakes shoreline. In the last three years, local health departments have received almost $1 million to monitor 200 “high priority” beaches. The data are made available on the MDEQ’s Beach Monitoring website, along with results of “WaterWatch,” a survey that seeks data on self-reported illnesses believed to be associated with exposure to water or muck. The fact that such programs are necessary to reduce public exposure is testimony that we still have a way to go in reducing water-borne pathogens in the Great Lakes.
Type E Botulism
In late summer and fall of 2006, thousands of fish-eating birds washed up on stretches of the northern shorelines of Lakes Michigan and Huron. The extensive die-offs were particularly evident at the Sleeping Bear Dunes National Lakeshore where the carcasses of about 3,000 gulls, cormorants, grebes, mergansers, loons and white-winged scoters (a species of diving duck) littered more than 10 miles of Lake Michigan beach. Smaller numbers of dead birds were scattered elsewhere, including Delta and Schoolcraft Counties in the Upper Peninsula. In 2007 much greater numbers of water birds (40% of which were loons) were killed on the Upper Peninsula’s Lake Michigan shore. The cause was Type E botulism, a finding not totally unexpected since up to 25,000 birds had been dying of the disease annually in Lakes Erie, Huron and Ontario since 1999.
While government studies to determine causes were underway, birds kept dying. This past July, dead gulls and cormorants were found along Lake Michigan beaches at Ludington State Park, providing evidence that the disease was spreading.
Scientists have recently found that exotic species play a role in this alarming spread of Type E botulism. Zebra and quagga mussels—brought to Michigan in the ballast water of ocean-going ships—are filtering planktonic algae and nutrients, increasing water clarity, and concentrating toxins of Clostridium botulisum bacteria. When the water is warmest, huge colonies of zebra and quagga mussels and growth of Cladophera (favored by increased light penetration to the lake bottom) combine to create nutrient-rich, low-oxygen zones on the lake bottoms. Amongst the rotting carcasses of the exotic mussels and algae, the bacteria population booms. Parts of the ecological mess are fed on by an invasive, exotic fish species—the round goby. Finally, birds eat gobies or the mussels, get sick and die, and are in turn eaten by other scavengers.
Viral Hemorrhagic Septicemia
A new fish-killing virus arrived in the Great Lakes around 2002. Within three years, viral hemorrhagic septicemia (VHS) began killing huge numbers of fish from lower Lake Huron all the way to the St. Lawrence River. Some fish losses to VHS also occurred in northern Lake Huron. Since 2007, VHS outbreaks in fish have occurred in parts of Lake Michigan as well.
We know that VHS causes fish to bleed to death, usually from their eyes, and that the invasive exotic virus is a mutant strain of a saltwater virus found in fish off the coast of the Maritime Provinces in Canada. We know VHS came to us the same way as zebra and quagga mussels, gobies, and a host of other pests—from ship ballast water. What we don’t know is what to do about it. Monitoring indicates the distribution of VHS is still spotty. But it is expected to begin moving up Michigan rivers.
Biologists hope to slow its spread by disinfecting fish eggs at hatcheries as they did to curb bacterial kidney disease in the late 1980s and early 90s. But many have given up hope of keeping it out of all five Great Lakes.
SERIES SUMMARY
The federal government, the Council of Great Lakes Governors, each bordering state, and just about every politician around have all committed to protecting and restoring the Great Lakes. Many have called for a coordinated effort. But the solutions are complicated and difficult, and there is still no common vision or universally supported agenda.
We have made great strides during the past 50 years in reducing most pollutants, but areas of concerns remain. Many of the toxic substances of great concern are dropping into the Great Lakes from the atmosphere, and limiting those substances would require an international effort. Public health threats have been identified and reduced, but too many beaches are still being closed because of bacteria levels. Variability associated with climate cycles and trends, water temperatures, and lake levels make monitoring and predictions extremely difficult.
It is tempting to simply call for a lot more government spending to dredge harbor sediments, regulate outflows of toxic materials, overhaul combined sewer systems, and improve the quality of storm water runoff. But a lot more traditional spending for water quality improvement is likely to yield only marginal results in the Great Lakes in the future. And with money expected to be scarce in the next few decades, we might do more good by stopping the introduction of exotics, and by pulling out all stops to limit those already in Michigan waters, than any other actions. The challenge is to allocate resources optimally. That will require maintaining end-of-the pipe controls, but also emphasizing bold new approaches to restoring this precious international resource.
Dr. Patrick J. Rusz
Director of Wildlife Programs