Great Lakes

Great Lakes
A rare cloudless satellite view of the entire Great Lakes region, April 24, 2000.
A map showing the Great Lakes.
A map showing the Great Lakes and their watershed, with State, Provincial and International boundaries.
The Great Lakes after a storm in October 2011. The storm brought sediment and algae to the surface of the lakes.

The Great Lakes are a collection of freshwater lakes located in northeastern North America, on the Canada – United States border. Consisting of Lakes Superior, Michigan, Huron, Erie, and Ontario, they form the largest group of freshwater lakes on Earth by total surface, coming in second by volume behind Baikal in Russia.[1][2] The total surface is 94,250 square miles (244,106 km2), and the total volume (measured at the low water datum) is 5,439 cubic miles (22,671 km3).[3] The lakes are sometimes referred to as the North Coast or "Third Coast" by some citizens of the United States. The Great Lakes hold 21% of the world's surface fresh water.[4]

Contents

Geography

Though the five lakes reside in separate basins, they form a single, naturally interconnected body of freshwater. The lakes form a chain connecting the east-central interior of North America to the Atlantic Ocean. From the interior to the outlet at the St. Lawrence River, water flows from Superior to Michigan-Huron (hydrologically a single body of water), southward to Erie, and finally northward to Lake Ontario. The lakes drain a large watershed via many rivers, and are studded with approximately 35,000 islands. The Great Lakes region contains not only the five themselves, but also many thousands of smaller lakes, often called inland lakes. Of the five lakes, Lake Michigan is the only one that is located entirely within the United States; the others form a water border between the United States and Canada.

Bathymetry

Lake Erie Lake Huron Lake Michigan Lake Ontario Lake Superior
Surface area[3] 9,910 sq mi (25,700 km2) 23,000 sq mi (60,000 km2) 22,300 sq mi (58,000 km2) 7,340 sq mi (19,000 km2) 31,700 sq mi (82,000 km2)
Water volume[3] 116 cu mi (480 km3) 850 cu mi (3,500 km3) 1,180 cu mi (4,900 km3) 393 cu mi (1,640 km3) 2,900 cu mi (12,000 km3)
Elevation[5] 571 ft (174 m) 577 ft (176 m) 577 ft (176 m) 246 ft (75 m) 600 ft (180 m)
Average depth[6] 62 ft (19 m) 195 ft (59 m) 279 ft (85 m) 283 ft (86 m) 483 ft (147 m)
Maximum depth 210 ft (64 m) 770 ft (230 m) 923 ft (281 m) 808 ft (246 m) 1,332 ft (406 m)
Major settlements[7] Buffalo, NY
Cleveland, OH
Erie, PA
Toledo, OH
Alpena, MI
Bay City, MI
Owen Sound, ON
Port Huron, MI
Sarnia, ON
Chicago, IL
Gary, IN
Green Bay, WI
Michigan City, IN
Milwaukee, WI
Muskegon, MI
Traverse City, MI
Hamilton, ON
Kingston, ON
Mississauga, ON
Oshawa, ON
Rochester, NY
Toronto, ON
Pickering, ON
Duluth, MN
Marquette, MI
Sault Ste. Marie, MI
Sault Ste. Marie, ON
Superior, WI
Thunder Bay, ON
Relative elevations, average depths, maximum depths, and volumes of the Great Lakes.

Notes: The area of each rectangle is proportionate to the volume of each lake. All measurements at Low Water Datum.
Source: EPA[5]
Great Lakes: System Profile

Because the surfaces of Lakes Superior, Huron, Michigan, and Erie are all approximately the same elevation above sea level while Lake Ontario is significantly lower and because Niagara Falls prevents all natural navigation, the four upper lakes are commonly called the "upper great lakes". This designation, however, is not universal. Those living on the shore of Lake Superior often refer to all the other lakes as "the lower lakes", for they are all lower. Sailors of bulk freighters transferring cargoes from Lake Superior and northern Lake Michigan-Huron to ports on Lake Erie or Ontario commonly refer to the latter as the lower lakes and Lakes Michigan, Huron, and Superior as the upper lakes. This corresponds to thinking of Lakes Erie and Ontario as "down south" and the others as "up north". Vessels sailing north on Lake Michigan are considered "upbound" even though they are sailing toward its effluent.

Water levels

Water levels of Lake Michigan have remained fairly constant over the past century. In fact the variance has only been about two meters during that timeframe. However, according to Science Daily, in the next century, we can expect the variance to be much higher. The Great Lakes are affected by three prominent air systems. There is a very dry and cold arctic system which comes from the North, another dry, but warm Pacific system that comes from the West, and finally, the system that evens it all out, a warm, wet tropical system from the south and the Gulf of Mexico.[8]

Lake Michigan-Huron

Lakes Michigan and Huron are hydrologically a single lake, sometimes called Lake Michigan-Huron; they have the same surface elevation of 577 feet (176 m),[9] and are connected not by a river but by the 295-foot (90 m) deep Straits of Mackinac.[6]

Rivers

Chicago on Lake Michigan is the largest city on the Great Lakes
Toronto on Lake Ontario is the second largest city on the Great Lakes
Detroit is the third largest metropolitan area linking Great Lakes system and the region's central metropolitan area.

Other bodies of water

  • Georgian Bay is a large bay located within Lake Huron, separated by the Bruce Peninsula and Manitoulin Island. It contains the majority of the islands of the Great Lakes, with a count of approximately 30,000. The North Channel, a narrower westerly extension of Georgian Bay, separates Manitoulin Island from mainland Northern Ontario.
  • The Straits of Mackinac connect Lake Michigan to Lake Huron.
  • The Welland Canal connects Lake Erie to Lake Ontario, bypassing the Niagara River which cannot be fully navigated due to the presence of Niagara Falls.
  • Lake St. Clair is the smallest lake in the Great Lake system but efforts have been made for consideration as one of the Great Lakes.
  • Lake Nipigon to the north of Lake Superior was formed by an extension or aulacogen of the Midcontinent Rift System which also formed Lake Superior, so the two lake beds are connected by shared geology.

Islands

Dispersed throughout the Great Lakes are approximately 35,000 islands. The largest among them is Manitoulin Island in Lake Huron, the largest island in any inland body of water in the world. The second-largest island is Isle Royale in Lake Superior. Both of these islands are large enough to contain multiple lakes themselves — Manitoulin Island's Lake Manitou is listed in the Guinness Book of World Records as the world's largest lake located on a freshwater island.

Connection to the ocean

The Saint Lawrence Seaway and Great Lakes Waterway opened the Great Lakes to ocean-going vessels. The move to wider ocean-going container ships — which do not fit through the locks on these routes — has limited container shipping on the lakes. Most Great Lakes trade is of bulk material and bulk freighters of Seawaymax-size or less can move throughout the entire lakes and out to the Atlantic. Larger ships are confined to working in the lakes themselves, only barges can access the Illinois Waterway system providing access to the Gulf of Mexico. Despite their vast size, large sections of the Great Lakes freeze over in winter, interrupting most shipping. Some icebreakers ply the lakes, keeping the shipping lanes open through most of the winter.

The Great Lakes are also connected to the Gulf of Mexico by way of the Illinois River (from the Chicago River) and the Mississippi River. An alternate track is via the Illinois River (from Chicago), to the Mississippi, up the Ohio, and then through the Tennessee-Tombigbee Waterway (combination of a series of rivers and lakes and canals), to Mobile Bay and the Gulf. Commercial tug-and-barge traffic on these waterways is heavy.

Pleasure boats can also enter or exit the Great Lakes by way of the Erie Canal and Hudson River in New York. The Erie Canal connects to the Great Lakes at the east end of Lake Erie (at Buffalo, NY) and at the south side of Lake Ontario (at Oswego, NY).

Boundaries

The lakes are bound by the Canadian province of Ontario and the U.S. states of Michigan, Wisconsin, Minnesota, Illinois, Indiana, Ohio, Pennsylvania, and New York. Four of the five lakes form part of the Canada-United States border; the fifth, Lake Michigan, is contained entirely within the United States. The Saint Lawrence River, which marks the same international border for a portion of its course, is the primary outlet of these interconnected lakes, and flows through Quebec and past the Gaspé Peninsula to the northern Atlantic Ocean.

Name origins

Lake Erie Lake Huron Lake Michigan Lake Ontario Lake Superior
Origins of Name Erie (tribe); shorten form of Iroquoian word Erielhonan or “long tail” Named by French explorers for inhabitants in the area, Wyandot or “Hurons” Likely from the Ojibwa word mishigami meaning “great water” Wyandot (Huron) word ontarío meaning “Lake of Shining Waters” (Ontara = beautiful, Ontario = beautiful lake) English translation of French term “lac supérieur” ("upper lake"), referring to its position above Lake Huron, Ojibwe called it "Gitchigumi"

Statistics

The Great Lakes contain roughly 22% of the world’s fresh surface water: 5,472 cubic miles (22,810 km3), or 6.0×1015 U.S. gallons (2.3×1016 liters). This is enough water to cover the 48 contiguous U.S. states to a uniform depth of 9.5 feet (2.9 m). However, only 2% of this volume is replaced each year, causing water levels to fall in recent years as the water undergoes heavy human use[citation needed]. Although the lakes contain a large percentage of the world's fresh water, the Great Lakes supply only a small portion of U.S. drinking water on a national basis (roughly 4.2%).[citation needed]

Winter 2009–10 was somewhat mild, the precipitation was below normal for the Great Lakes Basin. Mean lake levels are thought to be slightly below or at their levels of 2009. An ice jam in February 2010 dropped the level in Lake St. Clair. Since the jam was removed the level has come back to its average. As of March 2010, the lakes were at the level, or slightly below, where they were in March 2009.[10]

The combined surface area of the lakes is approximately 94,250 square miles (244,100 km2)—nearly the same size as the United Kingdom, and larger than the U.S. states of New York, New Jersey, Connecticut, Rhode Island, Massachusetts, Vermont and New Hampshire combined.

The Great Lakes coast measures approximately 10,500 miles (16,900 km);[6] however, the length of a coastline is impossible to measure exactly and is not a well-defined measure (see Coastline paradox).

Geology

A diagram of the formation of the Great Lakes.

It has been estimated that the foundational geology which created the conditions shaping the present day upper Great Lakes was laid from 1.1 to 1.2 billion years ago,[6][11] when two previously fused tectonic plates split apart and created the Midcontinent Rift, which crossed the Great Lakes Tectonic Zone. A valley was formed providing a basin that eventually became modern day Lake Superior. When a second fault line, the Saint Lawrence rift, formed approximately 570 million years ago,[6] the basis for Lakes Ontario and Erie were created, along with what would become the St. Lawrence River.

The Great Lakes are estimated to have been formed at the end of the last glacial period (about 10,000 years ago), when the Laurentide ice sheet receded. The retreat of the ice sheet left behind a large amount of meltwater (see Lake Agassiz) which filled up the basins that the glaciers had carved, thus creating the Great Lakes as we know them today.[12] Because of the uneven nature of glacier erosion, some higher hills became Great Lakes islands. The Niagara Escarpment follows the contour of the Great Lakes between New York and Wisconsin.

Land below the glaciers "rebounded" as it was uncovered.[13] Because the glaciers covered some areas longer than others, this glacial rebound occurred at different rates.

Climate

Lake effect

The effect of the Great Lakes on weather in the region is called the lake effect. In winter, the lakes often have no ice in the middle. The prevailing winds from the west pick up the slightly warmer air and moisture from the lake surface. As the slightly warmer, moist air passes over the colder land surface, the moisture often produces heavy snowfall. This is similar to the effect of warmer air dropping snow as it passes over mountain ranges. During freezing weather, this "snow belt" receives regular snow fall from this localized weather pattern, especially along the eastern shore. Snow belts are found in Michigan, Ohio, Pennsylvania, Ontario, and New York.

The lakes also moderate seasonal temperatures to some degree, by absorbing heat and cooling the air in summer, then slowly radiating that heat in autumn. It protects against frost during the transitional weather, but it also keeps the summer time temperatures cooler than further inland. This temperature buffering produces areas known as "fruit belts", where fruit typically grown farther south can be produced. Western Michigan has apple and cherry orchards, and vineyards adjacent to the lake shore as far north as the Grand Traverse Bay. The eastern shore of Lake Michigan and the southern shore of Lake Erie have many wineries as a result of this, as does the Niagara Peninsula between Lake Erie and Lake Ontario. A similar phenomenon occurs in the Finger Lakes region of New York as well as Prince Edward County, Ontario on Lake Ontario's northeast shore. Related to lake effect, is the occurrence of fog over medium-sized areas, particularly along the shorelines of the lakes. This is most noticeable along Lake Superior's shores, due to its maritime climate.

The Great Lakes have been observed to help strengthen storms, such as Hurricane Hazel in 1954, and a frontal system in 2007 that spawned a few tornadoes in Michigan and Ontario, picking up warmth from the lakes to fuel them. Also observed in 1996, was a rare subtropical cyclone forming in Lake Huron, dubbed the 1996 Lake Huron cyclone.

Ecology

Ecological challenges

MODIS Satellite imagery of the Great Lakes on Jan. 5th, 2001 showing ice beginning to build up around the shores of each of the lakes, with snow on the ground.

The ecological history of the Great Lakes includes both great losses and enormous recovery; the system today is in the most obvious ways much healthier than it was a half-century ago, while in less apparent ways it remains seriously compromised.

Before the arrival of Europeans, the Great Lakes provided fish to the indigenous groups who lived near them. Early European settlers were astounded by both the variety and quantity of fish; there were 150 different species in the Great Lakes.[6] Historically, fish populations were the early indicator of the condition of the Lakes, and have remained one of the key indicators even in the current era of sophisticated analyses and measuring instruments. According to the bi-national (U.S. and Canadian) resource book, The Great Lakes: An Environmental Atlas and Resource Book, "the largest Great Lakes fish harvests were recorded in 1889 and 1899 at some 67,000 tonnes [147 million pounds]," though the beginning of environmental impacts on the fish can be traced back nearly a century prior to those years.

By 1801 the New York Legislature found it necessary to pass regulations curtailing obstructions to the natural migrations of Atlantic salmon from Lake Erie into their spawning channels. In the early 19th century, Upper Canada's government found it necessary to introduce similar legislation prohibiting the use of weirs and nets at the mouths of Lake Ontario’s tributaries. Other protective legislation was passed as well, but enforcement remained difficult and often quite spotty.

On both sides of the Canada–United States border, the proliferation of dams and impoundments multiplied, necessitating more regulatory efforts. The decline in fish populations was unmistakable by the middle of the 19th century, as the obstructions in the rivers prevented salmon and sturgeon from reaching their spawning grounds. The decline in salmon was recognized by Canadian officials and reported as virtually a complete absence by the end of the 1860s. The Wisconsin Fisheries Commission noted a reduction of roughly 25% in general fish harvests by 1875. Many Michigan rivers sport multiple dams that range from mere relics to those with serious loss of life potential. The state's dam removal budget has been frozen in recent years; in the 1990s, the state was removing one dam per year.

Overfishing was cited as responsible for the decline of the population of various whitefish, important because of their culinary desirability and, hence, economic consequence. Moreover, between 1879 and 1899, reported whitefish harvests declined from some 24.3 million pounds (11 million kg) to just over 9 million pounds (4 million kg). The population of giant freshwater mussels was eliminated as the mussels were harvested for use as buttons by early Great Lakes entrepreneurs.

There were other factors in the population declines besides overfishing and the problems posed by water obstructions. Logging in the Great Lakes region removed tree cover near stream channels which provide spawning grounds; this affected necessary shade and temperature-moderating conditions. Removal of tree cover also destabilized soil, allowing soil to be carried in greater quantity into the streambeds and even brought about more frequent flooding. Running cut logs down the Lakes’ tributary rivers also stirred bottom sediments. In 1884 the New York Fish Commission determined that the dumping of sawmill waste (chips and sawdust) was impacting fish populations.

In the development of ecological problems in the Great Lakes, it was the influx of parasitic lamprey populations after the development of the Erie Canal and the much later Welland Canal that led to the two federal governments attempting to work together. Despite a variety of efforts to eliminate or minimize the lamprey, by the mid-1950s the lake trout populations of Lakes Michigan and Huron were reduced by about 99%, with the lamprey deemed largely to blame. This led to the launch of the bi-national Great Lakes Fishery Commission.

The authoritative but now outdated 1972 book The Great Lakes: An Environmental Atlas and Resource Book noted that "only pockets remain of the once large commercial fishery." In the meanwhile however the great water quality improvements realized during the 1970s and 1980s, combined with successful salmonid stocking programs, have enabled the growth of a large recreational fishery.

Pollution

Major contributors to ecological problems in the Lakes and their surroundings have stemmed from urban runoff and sprawl, sewage disposal, and toxic industrial effluent. These, of course, also affect aquatic food chains, fish populations, and human health. Some of these glaring problem areas are what attracted the high-level publicity of Great Lakes ecological troubles in the 1960s and 1970s. Evidence of chemical pollution in the Lakes and their tributaries now stretch back for decades. In the 1960s Ohio’s Cuyahoga River (or more precisely a combination of oil, chemicals and trash floating atop it in Cleveland, which created a very flammable brown, oily film) ignited and smoldered, creating international headlines. Witnesses claimed that there was not much that could have stopped the fire, the only thing that could have prevented would have been for these companies to not dump toxic waste.

The Cuyahoga, and a TIME Magazine cover story about the "death" of Lake Erie, helped focus public and policymaker attention and inspire the first Earth Day events in 1970. New advocacy organizations such as the Lake Michigan Federation, founded in 1970 by Lee Botts, brought new public pressure to bear. The first U.S. Clean Water Act, signed by Pres. Richard Nixon in 1972, was a key step forward as was the innovative[14] bi-national Great Lakes Water Quality Agreement signed by Canada and the U.S. Thanks to a variety of steps taken to reduce industrial and municipal pollution discharges into the system, basic water quality had by the 1980s improved sharply and Lake Erie in particular was significantly healthier. The ongoing discharge of toxic substances has also been sharply reduced thanks to federal and state bans of substances like PCBs and DDT, though historic toxics remain embedded in harbor and rivermouth sediments in dozens of "Great Lakes Areas of Concern".

Mercury

A prime example of a very harmful chemical that comprises the majority of pollutants in the water is the metal, mercury. Up until 1970, mercury was not listed as a harmful chemical to watch out for, according to the United States Federal Water Quality Administration. Within the past 10 years mercury has become more apparent in water tests, which has led to increased illness issues. Mercury compounds were used in many paper mills to prevent slime from forming during their production, and chemical companies, such as Dow Chemical, used mercury to separate chlorine from brine solutions. Studies conducted by the Environmental Protection Agency have shown that when the mercury comes in contact with many of the bacteria and compounds in the fresh water, it forms the very toxic, inorganic methyl mercury. This form of mercury is not detrimental to a majority of fish types, but is very detrimental to people and other wildlife animals who consume the fish. Mercury has been known for health related problems such as birth defects in humans and animals, and the near extinction of eagles in the Great Lakes region.[15]

Raw sewage

The amount of raw sewage dumped into the waters poses a much larger threat. Sewage treatment plants have many recommendations and requirements on how they are supposed to filter chemicals and sewage through them, but a huge majority of the waste never actually goes through the treatment centers. The flow of sewage into the Lakes once was slightly useful to natural processes, but with the current development and population increases it has only been overwhelming these processes. Many decades ago the population in a variety of areas was very minimal, so pumping sewage directly into the water seemed like a very workable solution. However when the population continued to grow, the sewage problem only got worse. As the sewage mixes with the natural processes in the Lakes and surrounding areas, algae grows which results in rotting matter on the beaches, and good organic matter falling to the bottom. The more blockages there are in the water results in an oxygen deprivation, which pauses the natural processes of the Lakes.

Invasive species

Since the 19th century an estimated 160 species have invaded the Great Lakes ecosystem, with ship ballast being a primary suspected pathway,[16] causing severe economic and ecological impacts.[17] According to the Inland Seas Education Association, on average a new invasive species enters the Great Lakes every eight months.[17]

A zebra mussel-encrusted Vector Averaging Current Meter from Lake Michigan.

Two such infestations in the Great Lakes are the introduction of the zebra mussel, which was first discovered in 1988,[18] and quagga mussel in 1989. The mollusks are efficient filter feeders, competing with native mussels, and also reduce available food and spawning grounds for fish. Additionally the mussels hurt utility and manufacturing industries by clogging or blocking pipes. The U.S. Fish and Wildlife Service estimates that the economic impact of the zebra mussel will be about $5 billion over the next decade.[19]

The alewife first entered the system west of Lake Ontario via 19th-century canals. By the 1960s the small silver fish had become a familiar nuisance to beachgoers across Lakes Michigan, Huron and Erie as periodic mass dieoffs resulted in vast numbers of them washing up on shore; estimates by various governments have placed the percentage of Lake Michigan's biomass which was made up of alewives in the early 1960s as high as 90%. The various state and federal governments began stocking several species of salmonids in the late 1960s, including the native lake trout as well as non-native chinook and coho salmon; by the 1980s alewife populations had dropped drastically. Ironically, today the sharply lower numbers of alewives is seen as a problem by those involved in the large recreational fishing sector that has grown up particularly on Lake Michigan. [20] The ruffe, a small percid fish, became the most abundant fish species in Lake Superior's St. Louis River within five years of its detection in 1986. Its range, which has expanded to Lake Huron, poses a significant threat to the lower lake fishery.[21] Five years after first being observed in the St. Clair River, the round goby can now be found in all of the Great Lakes. The goby is considered undesirable for several reasons: it preys upon bottom-feeding fish, overruns optimal habitat, spawns multiple times a season and can survive poor water quality conditions.[22]

Several species of exotic water fleas have accidentally been introduced into the Great Lakes, such as the spiny waterflea, Bythotrephes longimanus, and the fishhook waterflea, Cercopagis pengoi, potentially having an effect on the zooplankton population. Several species of crayfish have also been introduced that may contend with native crayfish populations. More recently an electric fence has been set up across the Chicago Sanitary and Ship Canal in order to keep several species of invasive Asian carps out of the area. These fast-growing planktivorous fish have heavily colonized the Mississippi and Illinois river systems.[23] The sea lamprey is another example of a marine invasive species in the Great Lakes. [24] It has been suggested that invasive species, particularly zebra and quagga mussels, may be at least partially responsible for the collapse of the deepwater demersal fish community in Lake Huron,[25] as well as drastic unprecedented changes in the zooplankton community of the lake.[26]

History

A woodcut of Le Griffon

The brigantine Le Griffon, which was commissioned by René Robert Cavelier, Sieur de La Salle, was built at Cayuga Creek, near the southern end of the Niagara River, and became the first sailing ship to travel the upper Great Lakes on August 7, 1679.

During settlement, the Great Lakes and its rivers were the only practical means of moving people and freight. Barges from middle North America were able to reach the Atlantic Ocean from the Great Lakes when the Erie Canal opened in 1825. By 1848, with the opening of the Illinois and Michigan Canal at Chicago, direct access to the Mississippi River was possible from the lakes. With these two canals an all-inland water route was provided between New York City and New Orleans.

The main business of many of the passenger lines in the 19th century was transporting immigrants. Many of the larger cities owe their existence to their position on the lakes as a freight destination as well as for being a magnet for immigrants. After railroads and surface roads developed, the freight and passenger businesses dwindled and, except for ferries and a few foreign cruise ships, has now vanished.

The immigration routes still have an effect today. Immigrants often formed their own communities and some areas have a pronounced ethnicity, such as Dutch, German, Polish, Finnish, and many others. Since many immigrants settled for a time in New England before moving westward, many areas on the U.S. side of the Great Lakes also have a New England feel, especially in home styles and accent.

Since general freight these days is transported by railroads and trucks, domestic ships mostly move bulk cargoes, such as iron ore, coal and limestone for the steel industry. The domestic bulk freight developed because of the nearby mines. It was more economical to transport the ingredients for steel to centralized plants rather than try to make steel on the spot. Ingredients for steel, however, are not the only bulk shipments made. Grain exports are also a major cargo on the lakes.

In the 19th century and early 20th century, iron and other ores such as copper were shipped south on (downbound ships), and supplies, food, and coal were shipped north (upbound). Because of the location of the coal fields in Pennsylvania and West Virginia, and the general northeast track of the Appalachian Mountains, railroads naturally developed shipping routes that went due north to ports such as Erie, Pennsylvania and Ashtabula, Ohio.

Because the lake maritime community largely developed independently, it has some distinctive vocabulary. Ships, no matter the size, are called boats. When the sailing ships gave way to steamships, they were called steamboats—the same term used on the Mississippi. The ships also have a distinctive design (see Lake freighter). Ships that primarily trade on the lakes are known as lakers. Foreign boats are known as salties.

One of the more common sights on the lakes is the 1,000‑by‑105 foot (305-by-32 m), 78,850-long-ton (80,120-metric-ton) self-unloader. This is a laker with a conveyor belt system that can unload itself by swinging a crane over the side.[27] Today, the Great Lakes fleet is much smaller in numbers than it once was because of the increased use of overland freight, and a few larger ships replacing many small ones.

Economy

MV Paul R. Tregurtha is the last of the 1,000 ft vessels built, and is the current largest vessel on the Great lakes system, making her the current Queen of the Lakes.

The Great Lakes are today used as a major mode of transport for bulk goods. In 2002, 162 million net tons of dry bulk cargo were moved on the Lakes. This was, in order of volume: iron ore, grain and potash.[citation needed] The iron ore and much of the stone and coal are used in the steel industry. There is also some shipping of liquid and containerized cargo but most container ships cannot pass the locks on the Saint Lawrence Seaway because the ships are too wide. The total amount of shipping on the lakes has been on a downward trend for several years.

The Great Lakes are used to supply drinking water to tens of millions of people in bordering areas. This valuable resource is collectively administered by the state and provincial governments adjacent to the lakes.

Recreational boating and tourism are major industries on the Great Lakes. A few small cruise ships operate on the Great Lakes including a couple of sailing ships. Sport fishing, commercial fishing, and Native American fishing represent a U.S.$4 billion a year industry with salmon, whitefish, smelt, lake trout and walleye being major catches. In addition, all kinds of water sports can be found on the lakes. Unusually for inland waters, the Great Lakes provide the possibility of surfing, particularly in winter due to the effect of strong storms and waves.

Great Lakes Circle Tour

The Great Lakes Circle Tour is a designated scenic road system connecting all of the Great Lakes and the St. Lawrence River.[28]

Great Lakes passenger steamers

From 1844 through 1857, palace steamers carried passengers and cargo around the Great Lakes. Throughout the 20th century, large luxurious passenger steamers sailed from Chicago all the way to Detroit and Cleveland. These were primarily operated by the Detroit & Cleveland Navigation Company. Several ferries currently operate on the Great Lakes to carry passengers to various islands, including Isle Royale, Pelee Island, Mackinac Island, Beaver Island, Bois Blanc Island (Ontario), Bois Blanc Island (Michigan), Kelleys Island, South Bass Island, North Manitou Island, South Manitou Island, Harsens Island, Manitoulin Island, and the Toronto Islands. As of 2007, three car ferry services cross the Great Lakes, two on Lake Michigan: a steamer from Ludington, Michigan, to Manitowoc, Wisconsin, and a high speed catamaran from Milwaukee to Muskegon, Michigan, and one on Lake Erie: a boat from Kingsville, Ontario, or Leamington, Ontario, to Pelee Island, Ontario, then onto Sandusky, Ohio. An international ferry across Lake Ontario from Rochester, New York, to Toronto ran during 2004 and 2005, but is no longer in operation.

Some passenger steamers

Ship's name Year built Nationality Ship's name Year built Nationality Ship's name Year built Nationality
Niagara 1856 United States SS Christopher Columbus 1892 United States SS Eastland 1902 United States
Milwaukee Clipper 1904 United States SS Keewatin 1907 Canadian Comet 1857 United States

Shipwrecks

The large size of the Great Lakes increases the risk of water travel; storms and reefs are common threats. The lakes are prone to sudden and severe storms, particularly in the autumn, from late October until early December. Hundreds of ships have met their end on the lakes. The greatest concentration of shipwrecks lies near Thunder Bay (Michigan), beneath Lake Huron, near the point where eastbound and westbound shipping lanes converge.

The Lake Superior shipwreck coast from Grand Marais, Michigan, to Whitefish Point became known as the "Graveyard of the Great Lakes". More vessels have been lost in the Whitefish Point area than any other part of Lake Superior.[29] The Whitefish Point Underwater Preserve serves as an underwater museum to protect the many shipwrecks in this area.

The first shipwreck was Le Griffon, the first ship to sail the Great Lakes. Caught in a storm while trading furs between Green Bay and Michilimacinac, it sank during a storm[30] and has possibly been found.[31] The last major freighter wrecked on the lakes was the SS Edmund Fitzgerald, which sank on November 10, 1975, just over 17 miles (30 km) offshore from Whitefish Point. The largest loss of life in a shipwreck out on the lakes may have been that of the Lady Elgin, wrecked in 1860 with the loss of around 400 lives. In an incident at a Chicago dock in 1915, the SS Eastland rolled over while loading passengers, killing 841.

In August 2007, the Great Lakes Shipwreck Historical Society announced that it had found the wreckage of Cyprus, a 420-foot (130 m) long, century-old ore carrier. Cyprus sank during a Lake Superior storm on October 11, 1907, during its second voyage while hauling iron ore from Superior, Wisconsin, to Buffalo, New York. The entire crew of 23 drowned, except one, a man named Charles Pitz, who floated on a life raft for almost seven hours.[32]

In June 2008 deep sea divers in Lake Ontario found the wreck of the 1780 Royal Navy warship HMS Ontario in what has been described as an "archaeological miracle".[33] There are no plans to raise her as the site is being treated as a war grave.

In June 2010 the L.R. Doty was found in Lake Michigan by an exploration diving team led by Dive Boat Captain Jitka Hanakova from her boat the Molly V after sinking in October 1898.[34] The ship sank, probably rescuing a small schooner the Olive Jeanette, during a terrible storm. There are no plans to raise the ship as it would quickly deteriorate in open air.

Still missing are the two last warships to sink in the Great Lakes, Inkerman and Cerisoles Minesweepers, which vanished in Lake Superior during a blizzard in 1918. 78 lives were lost making it the largest loss of life in Lake Superior and the great unexplained loss of life in the Great Lakes.

Related articles

Political issues and legislation

Great Lakes water use and diversions

The International Joint Commission was established in 1909 to help prevent and resolve disputes relating to the use and quality of boundary waters, and to advise Canada and the United States on questions related to water resources. Concerns over diversion of Lake water are of concern to both Americans and Canadians. Some water is diverted through the Chicago River to operate the Illinois Waterway but the flow is limited by treaty. Possible schemes for bottled water plants and diversion to dry regions of the continent raise concerns. Under the U.S. "Water Resources Development Act",[35] diversion of water from the Great Lakes Basin requires the approval of all eight Great Lakes governors through the Great Lakes Commission, which rarely occurs. International treaties regulate large diversions. In 1998, the Canadian company Nova Group won approval from the Province of Ontario to withdraw 158,000,000 U.S. gallons (600,000 m3) of Lake Superior water annually to ship by tanker to Asian countries. Public outcry forced the company to abandon the plan before it began. Since that time, the eight Great Lakes Governors and the Premiers of Ontario and Quebec have negotiated the Great Lakes-St. Lawrence River Basin Sustainable Water Resources Agreement [36] and the Great Lakes-St. Lawrence River Basin Water Resources Compact [37] that would prevent most future diversion proposals and all long-distance ones. The agreements also strengthen protection against abusive water withdrawal practices within the Great Lakes basin. On December 13, 2005, the Governors and Premiers signed these two agreements, the first of which is between all ten jurisdictions. It is somewhat more detailed and protective, though its legal strength has not yet been tested in court. The second, the Great Lakes Compact, has been approved by the state legislatures of all eight states that border the Great Lakes as well as the U.S. Congress, and was signed into law by President George W. Bush on 3 October 2008.[38]

Coast Guard live fire exercises

In 2006, the United States Coast Guard (USCG) proposed a plan to designate 34 areas in the Great Lakes, at least five miles (8 km) offshore, as permanent safety zones for live fire machine gun practice. In August 2006 the plan was published in the Federal Register. The USCG reserved the right to hold target practice whenever the weather allowed with a two hour notice. These firing ranges would be open to the public when not in use. In response to requests from the public, the Coast Guard held a series of public meetings in nine U.S. cities to solicit comment. During these meetings many people voiced concerns about the plan and its impact on the environment.[39]

A preliminary health risk assessment stated that the "proposed training will result in no elevated risks for a freshwater system such as the Great Lakes using 'realistic worst case' assumptions, and further investigation is not recommended ... if typical rather than worst case assumptions were used, the predicted risk would be even less."[40] However, the assessment was based on lead levels after five years, and so one could infer that lead levels could meet or exceed EPA safe levels for lead after fifteen years.[41]

On December 18, 2006, the Coast Guard announced its decision to withdraw the entire proposal.[42] Officials said they would look into alternative ammunition, modifying the proposed zones and have more public dialogue before proposing a new plan.[43]

Great Lakes Collaboration Implementation Act

During the 109th United States Congress in 2006, the Great Lakes Collaboration Implementation Act (Bill HR5100) was introduced to enact the recommendations of the Great Lakes Regional Collaboration, an effort established in 2004 to produce a strategy for restoring and maintaining the Great Lakes. The bill was introduced by U.S. senators Mike DeWine and Carl Levin, along with representatives Vern Ehlers and Rahm Emanuel.[44]

The bill states that "the Great Lakes are on the brink of an ecologic catastrophe" and that "if the pattern of deterioration is not reversed immediately, the damage could be irreparable". It cites the closing of over 1,800 beaches in 2003, the 6,300-square-mile (16,300 km2) dead zone in Lake Erie, and the U.S.$500 million damage each year due to the zebra mussel as evidences that "a comprehensive restoration of the system is needed to prevent the Great Lakes from collapsing".[44]

A press release states that the bill aimed to stop the introduction and spreading of invasive species, prevent the Asian carp from invading the Great Lakes, phase out mercury, restore animal habitats, and prevent sewage contamination.[45]

The bill did not pass, and was subsequently introduced in the 111th United States Congress as Senate Bill 237, where it did not proceed past the committee stage; no such legislation as a whole is planned to be introduced in the 112th Congress.[46]

Additions to the five Great Lakes

Lake Champlain, a lake on the border between upstate New York and northwestern Vermont that is part of the Saint Lawrence-Great Lakes Watershed, briefly became labeled by the U.S. government as the sixth "Great Lake of the United States" on March 6, 1998, when President Clinton signed Senate Bill 927. This bill, which reauthorized the National Sea Grant Program, contained a line penned by Senator Patrick Leahy (D-VT) declaring Lake Champlain to be a Great Lake. Not coincidentally, this status allows neighboring states to apply for additional federal research and education funds allocated to these national resources. The claim was viewed with some amusement by other countries, particularly in the Canadian media, and the lake is small compared to other Canadian lakes (such as Great Bear Lake which has over 27 times more surface area). Following a small uproar (and several New York Times and Time Magazine[47] articles), the Great Lake status was rescinded on March 24, 1998 (although Vermont universities continue to receive funds to monitor and study the lake).

Similarly, there has been interest in making Lake St. Clair a Great Lake. In October 2002, backers planned to present such a proposal at the Great Lakes Commission annual meeting,[48] but ultimately withheld it as it appeared to them to have too little support.[49]

See also

Notes

  1. ^ "LUHNA Chapter 6: Historical Landcover Changes in the Great Lakes Region". Biology.usgs.gov. 2003-11-20. http://biology.usgs.gov/luhna/chap6.html. Retrieved 2011-02-19. 
  2. ^ Ghassemi, Fereidoun (2007). Inter-basin water transfer. Cambridge, Cambridge University Press. ISBN 0-52-186969-2. 
  3. ^ a b c "Great Lakes: Basic Information: Physical Facts". U.S. Government. May 25, 2011. http://www.epa.gov/glnpo/physfacts.html. Retrieved 19:05, Wednesday November 9, 2011 (UTC). 
  4. ^ "Great Lakes – U.S. EPA". Epa.gov. 2006-06-28. http://www.epa.gov/glnpo/basicinfo.html. Retrieved 2011-02-19. 
  5. ^ a b "Great Lakes Atlas: Factsheet #1" (in English and French). United States Environmental Protection Agency. March, 9th, 2006. http://www.epa.gov/glnpo/atlas/gl-fact1.html. Retrieved 2007-12-03. 
  6. ^ a b c d e f Grady, Wayne (2007). The Great Lakes. Vancouver: Greystone Books and David Suzuki Foundation. ISBN 9781553651970. 
  7. ^ See List of cities on the Great Lakes for a complete list.
  8. ^ "Great Lakes Water Levels Sensitive To Climate Change". Science Daily. January, 14th, 2009. http://www.sciencedaily.com/releases/2009/01/090113101122.htm. Retrieved 2010-04-14. 
  9. ^ Wright, John W. (ed.); Editors and reporters of The New York Times (2006). The New York Times Almanac (2007 ed.). New York, New York: Penguin Books. p. 64. ISBN 0-14-303820-6. 
  10. ^ "Water Levels of the Great Lakes". NOAA Great Lakes Environmental Research Laboratory. 2007. http://www.glerl.noaa.gov/pubs/brochures/lakelevels/lakelevels.pdf. Retrieved 2011-02-19. 
  11. ^ Van Schmus, W. R.; Hinze, W. J. (May 1985). "The Midcontinent Rift System". Annual Review of Earth and Planetary Sciences 13 (1): 345–83. doi:10.1146/annurev.ea.13.050185.002021. https://kuscholarworks.ku.edu/dspace/bitstream/1808/104/1/fac6cit13.pdf. Retrieved 2008-10-06. 
  12. ^ Larson, Grahame; Schaetzl, R. (2001). "Origin and evolution of the Great Lakes". Journal of Great Lakes Research (Internat. Assoc. Great Lakes Res.) 27 (4): 518–546. doi:10.1016/S0380-1330(01)70665-X. http://www.geo.msu.edu/schaetzl/PDFs/Larson-Great_lakes.pdf. Retrieved 2009-03-04. 
  13. ^ "Lake levels report weighs Great Lakes basin’s glacial legacy". Great Lakes Echo. 2009-06-08. http://greatlakesecho.org/2009/06/08/lake-levels-report-weighs-great-lakes-basins-glacial-legacy/. Retrieved 2011-02-19. 
  14. ^ "Evolution of the Great Lakes Water Quality Agreement", Paul Muldoon and Lee Botts, Michigan State University Press, 2005
  15. ^ "Mercury Spills". Idph.state.il.us. http://www.idph.state.il.us/envhealth/factsheets/mercuryspills.htm. Retrieved 2011-02-19. 
  16. ^ "New EPA rules to target invasive species; Invaders have plagued Great Lakes for years". The Blade. http://proquest.umi.com/pqdweb?did=1514525481&sid=1&Fmt=3&clientId=8991&RQT=309&VName=PQD. Retrieved 2009-01-25. 
  17. ^ a b "Our Threatened Great Lakes". Inland Seas Education Association. http://www.greatlakeseducation.org/about_isea/?id=204. Retrieved 2007-11-30. 
  18. ^ Baxter Bulletin – www.baxterbulletin.com[dead link]
  19. ^ "Great Lakes Aquatic Nuisance Species". Great Lakes Commission. 2007-03-27. http://www.glc.org/ans/. Retrieved 2007-11-30. 
  20. ^ Smith, Paul (2009-02-24). "Gobies up, alewives down in Lake Michigan". Journal Sentinel. http://www.jsonline.com/blogs/sports/40240287.html. Retrieved 6 August 2010. 
  21. ^ "Predicting Invasive Species in the Great Lakes". U.S. Environmental Protection Agency. http://www.epa.gov/ord/sciencenews/scinews_great_lakes.htm. Retrieved 6 August 2010. 
  22. ^ Glassner-Shwayder, Katherine (July, 2000). "Briefing Paper: Great Lakes Nonindigenous Invasive Species". Great Lakes Nonindigenous Invasive Species Workshop. http://www.glc.org/ans/pdf/briefpapercomplete.pdf. Retrieved 6 August 2010. 
  23. ^ "Asian Carp Risk Assessment for Canada by Fisheries and Oceans Canada". CSAS. http://www.dfo-mpo.gc.ca/csas/Csas/DocREC/2004/RES2004_103_E.pdf. Retrieved 6 August 2010. 
  24. ^ [Petromyzon marinus Linnaeus 1758 "Petromyzon marinus Linnaeus 1758"]. USGS. Petromyzon marinus Linnaeus 1758. Retrieved 6 August 2010. 
  25. ^ Riley, S. C. et al. 2008. Deepwater demersal fish community collapse in Lake Huron. Transactions of the American Fisheries Society 137: 1879–1890
  26. ^ Barbiero, R. P. et al. 2009. Recent shifts in the crustacean zooplankton community of Lake Huron. Canadian Journal of Fisheries and Aquatic Sciences 66: 816–828
  27. ^ Wharton, George. "Great Lakes Fleet Page Vessel Feature – Burns Harbor". Boatnerd. http://www.boatnerd.com/pictures/fleet/burnsharbor.htm. Retrieved 6 August 2010. 
  28. ^ "Great Lakes Circle Tour". Great-lakes.net. 2005-07-05. http://www.great-lakes.net/tourism/circletour/. Retrieved 2011-02-19. 
  29. ^ Stonehouse, Frederick (1985, 1998). Lake Superior’s Shipwreck Coast, p. 267, Avery Color Studios, Gwinn, Michigan, U.S.A. ISBN 0-932232-43-3.
  30. ^ Matile, Roger (April 11, 2004) "Has a famed Great Lakes mystery been solved?" Ledger-Sentinel, Oswego, Illinois.
  31. ^ France claims historic Great Lakes wreck, Randy Boswell, Canwest News Service, February 17, 2009.
  32. ^ "Century-old shipwreck discovered". Associated Press. 2007-09-10. http://www.msnbc.msn.com/id/20679934/from/RS.1/. Retrieved 2007-12-03. 
  33. ^ "Divers find 1780 British warship". BBC News. 2008-06-14. http://news.bbc.co.uk/1/hi/uk/7454578.stm. Retrieved 2008-06-15. 
  34. ^ "L.R. Doty, ship that sank in Lake Michigan 112 years ago, found largely intact near Milwaukee". Minneapolis-St. Paul, Minnesota, Star Tribune. 2010-06-24. http://www.startribune.com/local/97084514.html. Retrieved 2010-06-28. [dead link]
  35. ^ [1][dead link]
  36. ^ "Great Lakes—St" (PDF). http://www.cglg.org/projects/water/docs/12-13-05/Great_Lakes-St_Lawrence_River_Basin_Sustainable_Water_Resources_Agreement.pdf. Retrieved 2011-02-19. 
  37. ^ http://www.cglg.org/projects/water/docs/12-13-05/Great_Lakes-St_Lawrence_River_Basin_Water_Resources_Compact.pdf
  38. ^ [2][dead link]
  39. ^ Meg Jones (2006-11-08). "Trading shots on bullets". Milwaukee Journal Sentinel. http://www.jsonline.com/story/index.aspx?id=529028. Retrieved 2007-12-02. 
  40. ^ Representative Phil English (PA03) – English Praises Coast Guard’s Decision on Proposed Live Fire Zones[dead link]
  41. ^ "Preliminary Health Risk Assessment for Proposed U.S. Coast Guard. Weapons Training Exercises" (PDF). engineering-environmental Management, Inc.. January 2006. p. 89. http://dmses.dot.gov/docimages/pdf97/413051_web.pdf. Retrieved 2007-12-02. 
  42. ^ Kari Lydersen (2006-12-19). "Coast Guard Target-Practice Plan Misfires". Washington Post. http://www.washingtonpost.com/wp-dyn/content/article/2006/12/18/AR2006121800596_pf.html. Retrieved 2007-12-02. 
  43. ^ Deborad Weisberg (2006-12-24). "Fishing: Coast Guard reloads on firing range". Pittsburgh Post-Gazette. http://www.post-gazette.com/pg/06358/748661-358.stm. Retrieved 2007-12-02. 
  44. ^ a b "Great Lakes Collaboration Implementation Act", HR5100, U.S. Government, April 5, 2006
  45. ^ Emanuel, Ehlers (April 5, 2006) "Emanuel, Ehlers Introduce Great Lakes Regional Collaboration Implementation Act", Press Release
  46. ^ Brownback, Abby (2011-03-23). "Great Lakes bills die, funding decreases". PolitiFact.com. http://www.politifact.com/truth-o-meter/promises/obameter/promise/265/restore-the-great-lakes/. Retrieved 2011-03-30. 
  47. ^ Adams, Kathleen (1998-03-16). "Congress's attempt to dub Lake Champlain a 'Great Lake'". Time.com. http://www.time.com/time/magazine/article/0,9171,987998,00.html. Retrieved 2011-02-19. 
  48. ^ "Does size matter? Lake St. Clair advocates believe that it deserves to be called 'great'", The Plain Dealer, October 14, 2002.
  49. ^ "Great Lakes panel wants monster fish to stay away", The Plain Dealer, October 16, 2002.

Further reading

External links

Coordinates: 45°45′N 84°0′W / 45.75°N 84°W / 45.75; -84


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