Swimming in the Great Lakes
The people of the Great Lakes region are justifiably proud of their beautiful lakeshore beaches. However, these beaches are threatened by a variety of pollution sources and major environmental stresses, which contribute to contaminated beachwater that can make people sick. In 2012, out of all the areas measured, the Great Lakes region had the highest percentage of monitoring samples that exceeded the Environmental Protection Agency's health standards. Approximately 1 in every 10 samples taken in the region last year was more contaminated than EPA's standards allowed.
Climate Change is Hurting The Great Lakes
The impacts of climate change on water systems—changes in precipitation patterns and intensity, greater incidence of drought, increasing evaporation and water temperatures, reductions in lake and river ice, changes in soil moisture and runoff—are increasingly evident in the Great Lakes region. These shifts are magnified by other factors, including aging and failing infrastructure, runoff pollution, and invasive species.
Across the Great Lakes Basin, 2012 began with a mild winter, quickly followed by an early spring and a hot summer of record highs. As a historic drought crippled 65 percent of the country, the first five months of the year were the warmest on record for many Great Lakes cities. Lake Superior, the northernmost, coldest, and deepest of the five Great Lakes, recorded its warmest temperatures in at least a century.
Lakes Michigan and Huron, the hardest-hit of the five lakes, experienced record low levels this past winter. These conditions are troubling to the shipping industry, which spent the last year struggling to move cargo into ports with low water levels—a situation similar to the disruption of barge traffic on the Mississippi River.
The irregular weather, while specific to one year, illustrates a larger trend. Extreme drought and high temperatures have kept water levels in the Great Lakes below their long-term averages for the past 14 years. Over the past 43 years, Michigan has been the second-fastest-warming state in the country, followed by Minnesota and Wisconsin. From 1973 to 2011, annual ice cover on the Great Lakes shrank by 63 percent.
Reduced ice cover can have large impacts on the health of the Great Lakes. Increased light penetration promotes algae growth and the survival of invasive species. Without ice and snow coverage, the lakes suffer from water loss due to increased evaporation. Stable ice that once prevented shoreline and wetland erosion is disappearing—and, with it, parts of our beaches. Known for its signature perched dunes, Michigan's Sleeping Bear Dunes National Park is one of many Great Lakes parks vulnerable to increased erosion. The loss of winter ice and snow cover renders the dunes' sands vulnerable to wind and exposes the bluffs to undercutting waves.
The Great Lakes are also affected by extreme precipitation events. The frequency of extreme storms—those delivering more than 3 inches of precipitation in 24 hours—has increased significantly in recent years. In fact, seven in the past 12 years ranked at the top for the number of extreme storms in the Midwest since 1961. Storms are expected to become not only more frequent but also stronger. In southern Wisconsin, extreme precipitation events are projected to become 10 to 40 percent stronger; in Illinois, heavy downpours are already twice as frequent as they were a century ago; and winters and springs in Ohio are projected to experience 30 percent more precipitation, which could increase flooding risks to floodplain communities. ,,
The Great Lakes region also faces threats from a combination of outdated and failing infrastructure. The American Society of Civil Engineers' 2013 Infrastructure Report Card gave the nation's aging wastewater system a grade of D-plus. In the eight Great Lakes states, $100.6 billion in wastewater infrastructure investment is needed over the next 20 years to achieve a basic level of functionality.
Crumbling and outmoded infrastructure causes several problems that can pollute Great Lakes beaches. For one, aging sanitary sewer systems can leak or allow stormwater to infiltrate, causing overflows or treatment facility bypasses. These system failures often lead to human waste in our waterways. Beyond that, many cities have conventional stormwater systems that simply dump polluted runoff from buildings, streets, and parking lots into nearby water bodies; these systems collect and discharge stormwater that has picked up fecal matter, pesticides, and other pollutants before flowing into sewers. As high-intensity storm events occur more frequently, heavy rainfall will flush even more pollutants into waterways.
In addition, more than 70 percent of all combined sewers in the United States are located in the Great Lakes region. Combined sewers collect sanitary sewage and stormwater runoff within a single pipe system and route the mixture to sewage treatment plants. When heavy rainfall overwhelms these systems, they are designed to send excess flow through wastewater outfall locations into local waterways, including the Great Lakes, to prevent sewage from flooding homes and businesses. Of the five states with the highest number of outfall locations, four of them—Ohio, Indiana, Pennsylvania, and Illinois—have Great Lake shorelines. In 2010, these outfalls, along with outfalls in Michigan, Wisconsin, Minnesota, and New York, released 18.7 billion gallons of combined sewage and storm runoff into the Great Lakes.
As the frequency of extreme rainfall events increases, the instances of combined sewer overflows will also increase. In southern Wisconsin, the frequency of combined sewer overflows is expected to rise 50 to 120 percent by the end of the century. The problem of increasing volumes of combined sewage is so acute in Chicago that runoff has caused the Chicago River to reverse its flow. In the past five years, the river has reversed eight times, sending more than 20 billion gallons of contaminated water into Lake Michigan.
Threats to Human Health
Despite the size of the Great Lakes, pollution pouring into lake waters is a threat to human health. Untreated sewage can contain more than 120 viruses, two of which, Giardia and Cryptosporidium, can cause intestinal illnesses and even death.
These viruses and pollutants don't simply disappear under the lakes' surface. For example, in a study of four Ohio beaches, researchers frequently found Arcobacter, a pathogen associated with human and animal fecal contamination, at each beach. Arcobacter is known to cause gastrointestinal disease in humans.
Pollutants released into surface waters in the Great Lakes Basin increased by 12 percent from 2010 to 2011. Most of these are nitrates and pesticides from municipal wastewater treatment plants and agricultural sources. Primary metals facilities—such as iron and steel mills and smelters—and food and beverage manufacturers also contribute nitrate pollution.
As increasing temperatures reduce lake levels and increasing storm events dump more pollutants into the Great Lakes, it is expected that climate change will increase the concentration of pollutants in the Great Lakes as well as instances of beach contamination and closings in the future.
Algae And Invasive Species
Nitrogen and phosphorus in stormwater runoff, sewage from CSOs and water treatment plants, and agricultural runoff spur the growth of large, harmful algal blooms. These slimy mats of algae foul beaches and the taste of drinking water and produce toxins that are dangerous to humans. In 2011, a toxic algal mat blanketing Lake Erie was so massive it could be seen from space. Though algal blooms in 2012 weren't as extreme, experts fear that another infestation of harmful blooms will occur this year; indeed, there are indications that it is already happening.,
Dissolved reactive phosphorus loads from fertilizer and animal manure have increased 218 percent in Lake Erie since 1995. When algae feed off these excess nutrients, they overproduce. The growth of algae suffocates the Great Lakes by creating a condition called hypoxia, a depletion of oxygen levels in the water caused by their growth and decomposition. Similar to the "dead zone" in the Gulf of Mexico, hypoxia in the Great Lakes' aquatic ecosystem suffocates fish and other organisms.
NRDC and a coalition of top environmental groups are suing the EPA for its refusal to address this critical pollution problem, which it has acknowledged for decades: the contribution of nitrates and phosphorus to the growth of harmful algal blooms. The EPA called on states in 1998 to adopt specific limits on nitrogen and phosphorus pollution for their water bodies and promised to enact its own limits if states did not act by 2003. States have ignored the deadline, as has EPA, forcing the current litigation.
Temperature increases associated with climate change, including both rising overall temperatures and more extreme temperature fluctuations, also contribute to nutrient-fueled algal growth in the Great Lakes Cladophora, a green alga found in the Great Lakes, thrives in warmer temperatures. When toxic clumps of cladophora wash onto beaches, they become smelly breeding grounds for bacteria such as E. coli, enterococcus, and type B botulinum, creating high pathogen counts and triggering beach closures. Cladophora is also a threat to wildlife that depends on the Great Lakes. In the fall of 2012, nearly 900 loons died while migrating south across Lake Michigan. Scientists believe that type B botulinum fostered by the algae-rich environment worked its way up the food chain from tiny worms and invertebrates to the loons. Low water levels and high temperatures intensify these botulism outbreaks.
Cyanobacteria (blue-green algae), which produce the hepatoxin microcystin, pose another health threat. Acute exposure to the toxin can lead to gastrointestinal illness, while chronic exposure can result in liver disease and damage and possible tumor promotion.
Unfortunately, monitoring harmful algal blooms and their toxins is difficult, and methods for doing so are still under development. None of the Great Lakes states currently have harmful algal bloom monitoring in place to protect swimmers.
Another force abetting the growth of algae is the decimating impact of invasive species, such as quagga and zebra mussels and filter-feeding Asian carp. These invasive species relentlessly filter out plankton at the base of the food chain, increasing water clarity and promoting the growth of large mats of green algae on the lake floor. These mats can break free and eventually accumulate on the coast, fouling Great Lakes beaches.
While short-term efforts are under way to stop the Asian carp from moving into the Great Lakes, a longer-term solution is desperately needed. NRDC, along with other states and organizations, have pressed for the construction of a physical barrier between the Great Lakes and Mississippi River Basin to permanently solve this problem. At a recent meeting of the Great Lakes Commission, Illinois Governor Pat Quinn expressed his support for this position.
Great Lakes 2012 Beach Closing/Advisories And Pollution Sources
Total closing/advisory days for 1,683 events lasting six consecutive weeks or less increased 7% to 3,632 days in 2012 from 3,410 days in 2011. In prior years, there were 3,766 days in 2010, 3,300 days in 2009, and 3,437 days in 2008. In addition, there were no extended or permanent events in 2012. Extended events are those in effect more than six weeks but not more than 13 consecutive weeks; permanent events are in effect for more than 13 consecutive weeks. For the 1,683 events lasting six consecutive weeks or less, 91% (3,317) of closing/advisory days were due to monitoring that revealed elevated bacteria levels, 1% (48) were preemptive based on the results of computer modeling, 3% (96) were preemptive due to other reasons, and 6% (211) were preemptive due to heavy rainfall. (Totals exceed total days and 100% because more than one reason was reported for some events.)
Reported Sources of Beachwater Contamination (number of closing/advisory days)
- 2,995 (82%) unknown contamination sources
- 513 (14%) stormwater runoff
- 120 (3%) other contamination sources
- 4 (<1%) wildlife
Great Lakes 2012 Beach Water Quality
In 2012, Great Lakes states reported 1,144 coastal beaches, of which 41 (4%) were assigned a monitoring frequency of daily, 210 (18%) more than once a week, 354 (31%) once a week, 7 (1%) every other week, 1 (<1%) once a month, and 3 (<1%) less than once a month; 528 (46%) were not assigned a monitoring frequency. In 2012, 10% of all reported beach monitoring samples exceeded the national daily maximum bacterial standard of 235 colonies/100 ml. The beaches with the highest percent exceedance rates of the daily maximum standard in 2012 were Jeorse Park Beach I in Indiana (70%), Camp Perry in Ohio (70%), Wisconsin Point Beach 2 in Wisconsin (64%), Arcadia Beach in Ohio (57%), Jeorse Park Beach II in Indiana (52%), Lakeview Beach (52%) and Bay View West (49%) in Ohio, Bender Beach in Wisconsin (48%), Park Point 20th Street/Hearding Island Canal Beach in Minnesota (47%), and Port Clinton (Deep\Lakeview) (47%) and Lakeshore Park in Ohio (44%). Ohio had the highest exceedance rate of the daily maximum standard in 2012 (20%), followed by New York (Great Lakes beaches only, 14%), Wisconsin (14%), Minnesota (12%), Indiana (10%), Illinois (10%), Pennsylvania (9%), and Michigan (6%). NRDC considers all reported samples individually (without averaging) when calculating the percent exceedance rates in this analysis. This includes duplicate samples and samples taken outside the official beach season, if any.
Percent of Samples Exceeding the National Daily Maximum Bacterial Standard for 469 Beaches Reported 2008-2012
2012 Beachwater Quality Summary
Seven of the eight Great Lakes states use the BEACH Act single-sample standard to inform beach closing/advisory decisions. This standard is 235 cu/100 ml of E.coli. Michigan's single-sample standard is 300 cfu/100 ml of E. coli.
Four of the Great Lakes states use a geometric-mean standard based on at least five samples over a 30-day period to inform beach closing/advisory decisions. Michigan applies a geometric mean standard of 130 cfu/100 ml. Wisconsin, Minnesota, Pennsylvania also applies a geometric mean standard of 126 cfu/100 ml at high-priority beaches. In New York, local beach authorities decide whether to apply the geometric mean when making closing and advisory decisions. Illinois, Indiana, and Ohio do not apply the geometric-mean standard when making closing and advisory decisions.
If the Great Lakes St. Lawrence River region (including the U.S. and Canada) were its own country, it would be the fourth largest economy in the world. More than 1.5 million jobs in the U.S. are directly tied to the Great Lakes, with 200,000 jobs supported by recreation and tourism. Clearly, the damage inflicted on the Great Lakes has not only severe environmental and human health impacts, but wide-reaching economic effects as well. Closing all the breach sites on Lake Michigan alone could cost local economies as much as $2.7 billion.
In 2003, spending on boats and boating activities in the Great Lakes states totaled nearly $16 billion and directly supported 107,000 jobs. Yet increased evaporation due to an early spring and hot summer has lowered lake levels to a point where the recreational boating industry is starting to feel the impact of climate change. Low water levels make it difficult to move ships from deeper lake waters to shallow ports as well as shorten the boating season, impacting the livelihood of those who depend on Great Lakes recreation.
Low water also has serious implications for Great Lakes—St. Lawrence Seaway shipping, a $34 billion industry that impacts commodity and manufacturing costs as well as consumer prices. To cope with low water levels, ship owners are forced to lighten the loads on their boats, making each shipment less efficient and less profitable. In December and January, extreme drought reduced water levels on the Mississippi River and nearly halted the shipment of $7 billion worth of grain, coal, crude oil, and other products moving between the Great Lakes and the Gulf of Mexico.
The threats of failing infrastructure, algal blooms and climate change threaten more than regional and national economies—the Great Lakes are the source of 20 percent of the world's freshwater and the drinking water source for more than 30 million people in the U.S. alone.