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122-537: 37°34′11.6″N 121°59′49.18″W / 37.569889°N 121.9969944°W / 37.569889; -121.9969944 The Niles Cone is a groundwater basin in Alameda County, California , United States which is the source of drinking water for a sizeable human urban population in the East Bay . The land area corresponding to this groundwater basin is approximately 103 square miles; (California, 1998)
244-511: A coastline is impossible to measure exactly . Canada borders approximately 5,200 miles (8,400 km) of coastline, while the remaining 5,300 miles (8,500 km) are bordered by the United States. Michigan has the longest shoreline of the United States, bordering roughly 3,288 miles (5,292 km) of lakes, followed by Wisconsin (820 miles (1,320 km)), New York (473 miles (761 km)), and Ohio (312 miles (502 km)). Traversing
366-408: A drop in the ground surface. In unconsolidated aquifers, groundwater is produced from pore spaces between particles of gravel, sand, and silt. If the aquifer is confined by low-permeability layers, the reduced water pressure in the sand and gravel causes slow drainage of water from the adjoining confining layers. If these confining layers are composed of compressible silt or clay, the loss of water to
488-402: A former lake bed, has experienced rates of subsidence of up to 40 centimetres (1 foot 4 inches) per year. For coastal cities, subsidence can increase the risk of other environmental issues, such as sea level rise . For example, Bangkok is expected to have 5.138 million people exposed to coastal flooding by 2070 because of these combining factors. If the surface water source
610-1076: A global level, although priority chemicals will vary by country. There is a lot of heterogeneity of hydrogeologic properties. For this reason, salinity of groundwater is often highly variable over space. This contributes to highly variable groundwater security risks even within a specific region. Salinity in groundwater makes the water unpalatable and unusable and often occurs in coastal areas, for example in Bangladesh and East and West Africa. Municipal and industrial water supplies are provided through large wells. Multiple wells for one water supply source are termed "wellfields", which may withdraw water from confined or unconfined aquifers. Using groundwater from deep, confined aquifers provides more protection from surface water contamination. Some wells, termed "collector wells", are specifically designed to induce infiltration of surface (usually river) water. Aquifers that provide sustainable fresh groundwater to urban areas and for agricultural irrigation are typically close to
732-408: A home and then returned to the ground in another well. During cold seasons, because it is relatively warm, the water can be used in the same way as a source of heat for heat pumps that is much more efficient than using air. Groundwater makes up about thirty percent of the world's fresh water supply, which is about 0.76% of the entire world's water, including oceans and permanent ice. About 99% of
854-533: A large watershed via many rivers and contain approximately 35,000 islands. There are also several thousand smaller lakes, often called "inland lakes", within the basin. The surface area of the five primary lakes combined is roughly equal to the size of the United Kingdom, while the surface area of the entire basin (the lakes and the land they drain) is about the size of the UK and France combined. Lake Michigan
976-519: A long time without severe consequences. Nevertheless, over the long term the average rate of seepage above a groundwater source is the upper bound for average consumption of water from that source. Groundwater is naturally replenished by surface water from precipitation , streams , and rivers when this recharge reaches the water table. Groundwater can be a long-term ' reservoir ' of the natural water cycle (with residence times from days to millennia), as opposed to short-term water reservoirs like
1098-405: A national basis. The total surface area of the lakes is approximately 94,250 square miles (244,100 km )—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), but the length of
1220-456: A nuisance to industries by clogging pipes. The U.S. Fish and Wildlife Service estimated in 2007 that the economic impact of the zebra mussel could be about $ 5 billion over the next decade. 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 beach goers across Lakes Michigan, Huron, and Erie. Periodic mass die-offs result in vast numbers of
1342-722: A permanently reduced capacity to hold water. The city of New Orleans, Louisiana is actually below sea level today, and its subsidence is partly caused by removal of groundwater from the various aquifer/aquitard systems beneath it. In the first half of the 20th century, the San Joaquin Valley experienced significant subsidence , in some places up to 8.5 metres (28 feet) due to groundwater removal. Cities on river deltas, including Venice in Italy, and Bangkok in Thailand, have experienced surface subsidence; Mexico City, built on
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#17327805674801464-681: A possible reason for a decrease in 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). By 1900, commercial fishermen on Lake Michigan were hauling in an average of 41 million pounds of fish annually. By 1938, Wisconsin's commercial fishing operations were motorized and mechanized, generating jobs for more than 2,000 workers, and hauling 14 million pounds per year. The population of giant freshwater mussels
1586-560: A relatively small area of southeast Lake Michigan where savanna or prairie occasionally intruded). Logging, urbanization, and agriculture uses have changed that relationship. In the early 21st century, Lake Superior's shores are 91% forested, Lake Huron 68%, Lake Ontario 49%, Lake Michigan 41%, and Lake Erie, where logging and urbanization has been most extensive, 21%. Some of these forests are second or third growth (i.e. they have been logged before, changing their composition). At least 13 wildlife species are documented as becoming extinct since
1708-489: A season, and can survive poor water quality conditions. The influx of parasitic lamprey populations after the development of the Erie Canal and the much later Welland Canal led to the two federal governments of the United States and Canada working on joint proposals to control it. By the mid-1950s, the lake trout populations of Lakes Michigan and Huron were reduced, with the lamprey deemed largely to blame. This led to
1830-746: A second fault line, the Saint Lawrence rift , formed approximately 570 million years ago, the basis for Lakes Ontario and Erie was created, along with what would become the Saint Lawrence River. The Great Lakes are estimated to have been formed at the end of the Last Glacial Period (the Wisconsin glaciation ended 10,000 to 12,000 years ago), when the Laurentide Ice Sheet receded. The retreat of
1952-712: A single body of water, as they are joined by Straits of Mackinac .) The Great Lakes Waterway enables modern travel and shipping by water among the lakes. The lakes connect to the Atlantic Ocean via the Saint Lawrence River , and to the Mississippi River basin through the Illinois Waterway . The Great Lakes are the largest group of freshwater lakes on Earth by total area and the second-largest by total volume. They contain 21% of
2074-689: A small percid fish from Eurasia, became the most abundant fish species in Lake Superior's Saint 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. 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
2196-414: Is "new" water, originating from rivers, precipitation, and groundwater springs. In the post-glacial period, evaporation , and drainage have generally been balanced, making the levels of the lakes relatively constant. Intensive human population growth began in the region in the 20th century and continues today. At least two human water use activities have been identified as having the potential to affect
2318-399: Is a highly useful and often abundant resource. Most land areas on Earth have some form of aquifer underlying them, sometimes at significant depths. In some cases, these aquifers are rapidly being depleted by the human population. Such over-use, over-abstraction or overdraft can cause major problems to human users and to the environment. The most evident problem (as far as human groundwater use
2440-528: Is also often withdrawn for agricultural , municipal , and industrial use by constructing and operating extraction wells . The study of the distribution and movement of groundwater is hydrogeology , also called groundwater hydrology . Typically, groundwater is thought of as water flowing through shallow aquifers, but, in the technical sense, it can also contain soil moisture , permafrost (frozen soil), immobile water in very low permeability bedrock , and deep geothermal or oil formation water. Groundwater
2562-466: Is also subject to substantial evaporation, a groundwater source may become saline . This situation can occur naturally under endorheic bodies of water, or artificially under irrigated farmland. In coastal areas, human use of a groundwater source may cause the direction of seepage to ocean to reverse which can also cause soil salinization . As water moves through the landscape, it collects soluble salts, mainly sodium chloride . Where such water enters
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#17327805674802684-632: Is an additional water source that was not used previously. First, flood mitigation schemes, intended to protect infrastructure built on floodplains, have had the unintended consequence of reducing aquifer recharge associated with natural flooding. Second, prolonged depletion of groundwater in extensive aquifers can result in land subsidence , with associated infrastructure damage – as well as, third, saline intrusion . Fourth, draining acid sulphate soils, often found in low-lying coastal plains, can result in acidification and pollution of formerly freshwater and estuarine streams. Groundwater
2806-417: Is concerned) is a lowering of the water table beyond the reach of existing wells. As a consequence, wells must be drilled deeper to reach the groundwater; in some places (e.g., California , Texas , and India ) the water table has dropped hundreds of feet because of extensive well pumping. The GRACE satellites have collected data that demonstrates 21 of Earth's 37 major aquifers are undergoing depletion. In
2928-633: Is flat according to the International Joint Commission. Reports about this issue on the U.S. side highlight five large municipal systems (those of Detroit, Cleveland, Buffalo, Milwaukee and Gary ) as being the largest current periodic sources of untreated discharges into the Great Lakes. The fish of the Great Lakes have anti-depressant drugs meant for humans in their brains, which has caused concerns. The number of American adults who take anti-depressant drugs rose from 7.7% of all American adults in 1999–2002 to 12.7% in 2011–2014. As
3050-412: Is fresh water located in the subsurface pore space of soil and rocks . It is also water that is flowing within aquifers below the water table . Sometimes it is useful to make a distinction between groundwater that is closely associated with surface water , and deep groundwater in an aquifer (called " fossil water " if it infiltrated into the ground millennia ago ). Groundwater can be thought of in
3172-557: Is heavy. Pleasure boats can 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, New York ) and at the south side of Lake Ontario (at Oswego, New York ). The lakes were originally fed by both precipitation and meltwater from glaciers which are no longer present. In modern times, only about 1% of volume per year
3294-427: Is hypothesized to provide lubrication that can possibly influence the movement of faults . It is likely that much of Earth 's subsurface contains some water, which may be mixed with other fluids in some instances. Groundwater is often cheaper, more convenient and less vulnerable to pollution than surface water . Therefore, it is commonly used for public drinking water supplies. For example, groundwater provides
3416-545: Is less visible and more difficult to clean up than pollution in rivers and lakes. Groundwater pollution most often results from improper disposal of wastes on land. Major sources include industrial and household chemicals and garbage landfills , excessive fertilizers and pesticides used in agriculture, industrial waste lagoons, tailings and process wastewater from mines, industrial fracking , oil field brine pits, leaking underground oil storage tanks and pipelines, sewage sludge and septic systems . Additionally, groundwater
3538-468: Is rapidly increasing with population growth, while climate change is imposing additional stress on water resources and raising the probability of severe drought occurrence. The anthropogenic effects on groundwater resources are mainly due to groundwater pumping and the indirect effects of irrigation and land use changes. Groundwater plays a central role in sustaining water supplies and livelihoods in sub-Saharan Africa . In some cases, groundwater
3660-560: Is susceptible to saltwater intrusion in coastal areas and can cause land subsidence when extracted unsustainably, leading to sinking cities (like Bangkok ) and loss in elevation (such as the multiple meters lost in the Central Valley of California ). These issues are made more complicated by sea level rise and other effects of climate change , particularly those on the water cycle . Earth's axial tilt has shifted 31 inches because of human groundwater pumping. Groundwater
3782-400: Is the most accessed source of freshwater around the world, including as drinking water , irrigation , and manufacturing . Groundwater accounts for about half of the world's drinking water, 40% of its irrigation water, and a third of water for industrial purposes. Another estimate stated that globally groundwater accounts for about one third of all water withdrawals , and surface water for
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3904-515: Is the only one of the Great Lakes that is entirely within the United States; the others form a water boundary between the United States and Canada. The lakes are divided among the jurisdictions of the Canadian province of Ontario and the U.S. states of Michigan , Wisconsin , Minnesota , Illinois , Indiana , Ohio , Pennsylvania , and New York . Both the province of Ontario and the state of Michigan include in their boundaries portions of four of
4026-456: Is used for irrigation. Occasionally, sedimentary or "fossil" aquifers are used to provide irrigation and drinking water to urban areas. In Libya, for example, Muammar Gaddafi's Great Manmade River project has pumped large amounts of groundwater from aquifers beneath the Sahara to populous areas near the coast. Though this has saved Libya money over the alternative, seawater desalination,
4148-995: The Chicago Sanitary and Ship Canal to the Gulf of Mexico via 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 (a combination of a series of rivers and lakes and canals), to Mobile Bay and the Gulf of Mexico. Commercial tug -and- barge traffic on these waterways
4270-876: The Door Peninsula , the Peninsulas of Michigan , and the Ontario Peninsula . Some of these peninsulas even contain smaller peninsulas, such as the Bruce , Keweenaw , Leelanau , Niagara , and Thumb peninsulas. Population centers on the peninsulas include Grand Rapids , Flint , and Detroit in Michigan along with London , Hamilton , Brantford , and Toronto in Ontario. Although the Saint Lawrence Seaway and Great Lakes Waterway make
4392-529: 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 compound methyl mercury , which has a much greater impact on human health than elemental mercury due to a higher propensity for absorption. 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
4514-690: The Finger Lakes region of New York, as well as in Prince Edward County, Ontario , on Lake Ontario's northeast shore. The Great Lakes have been observed to help intensify storms, such as Hurricane Hazel in 1954, and the 2011 Goderich, Ontario tornado , which moved onshore as a tornadic waterspout . In 1996, a rare tropical or subtropical storm was observed forming in Lake Huron, dubbed the 1996 Lake Huron cyclone . Rather large severe thunderstorms covering wide areas are well known in
4636-521: The Niagara Escarpment precludes all natural navigation, the four upper lakes are commonly called the "upper great lakes". This designation is not universal. Those living on the shore of Lake Superior often refer to all the other lakes as "the lower lakes", because they are farther south. Sailors of bulk freighters transferring cargoes from Lake Superior and northern Lake Michigan and Lake Huron to ports on Lake Erie or Ontario commonly refer to
4758-782: The Niles Cone Basin is bounded on the east by the Diablo Range and on the west by San Francisco Bay . Surface runoff in the Alameda Creek catchment basin accounts for much of the recharge of the Niles Cone. (Niles Cone, 2007) The Alameda County Water District is responsible for management of the Niles Cone aquifer and has developed water treatment plants and pipelines for the conveyance of its waters to urban users. (Earth Metrics, 1990) The Alameda County Water District also performs water quality monitoring of
4880-585: The Punjab region of India , for example, groundwater levels have dropped 10 meters since 1979, and the rate of depletion is accelerating. A lowered water table may, in turn, cause other problems such as groundwater-related subsidence and saltwater intrusion . Another cause for concern is that groundwater drawdown from over-allocated aquifers has the potential to cause severe damage to both terrestrial and aquatic ecosystems – in some cases very conspicuously but in others quite imperceptibly because of
5002-510: The biosphere . Since the 19th century, an estimated 160 new species have found their way into the Great Lakes ecosystem; many have become invasive; the overseas ship ballast and ship hull parasitism are causing severe economic and ecological impacts. According to the Inland Seas Education Association, on average a new species enters the Great Lakes every eight months. Introductions into the Great Lakes include
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5124-442: The hydraulic pressure of groundwater in the pore spaces of the aquifer and the aquitard supports some of the weight of the overlying sediments. When groundwater is removed from aquifers by excessive pumping, pore pressures in the aquifer drop and compression of the aquifer may occur. This compression may be partially recoverable if pressures rebound, but much of it is not. When the aquifer gets compressed, it may cause land subsidence,
5246-405: The vadose zone below plant roots and is often expressed as a flux to the water table surface. Groundwater recharge also encompasses water moving away from the water table farther into the saturated zone. Recharge occurs both naturally (through the water cycle ) and through anthropogenic processes (i.e., "artificial groundwater recharge"), where rainwater and/or reclaimed water is routed to
5368-414: The zebra mussel , which was first discovered in 1988, and quagga mussel in 1989. Since 2000, the invasive quagga mussel has smothered the bottom of Lake Michigan almost from shore to shore, and their numbers are estimated at 900 trillion. The mollusks are efficient filter feeders, competing with native mussels and reducing available food and spawning grounds for fish. In addition, the mussels may be
5490-584: The " snowbelts " receive regular snow fall from this localized weather pattern, especially along the eastern shores of the lakes. Snowbelts are found in Wisconsin, Michigan, Ohio, Pennsylvania, New York, and Ontario. Related to the lake effect is the regular occurrence of fog, particularly along the shorelines of the lakes. This is most noticeable along Lake Superior's shores. The lakes tend to moderate seasonal temperatures to some degree but not with as large an influence as do large oceans; they absorb heat and cool
5612-632: The Canadian side, Toronto , Hamilton and Mississauga . Though the five lakes lie in separate basins, they form a single, naturally interconnected body of fresh water, within the Great Lakes Basin . As a chain of lakes and rivers, they connect the east-central interior of North America to the Atlantic Ocean. From the interior to the outlet at the Saint Lawrence River, water flows from Superior to Huron and Michigan, southward to Erie, and finally northward to Lake Ontario. The lakes drain
5734-497: The Chicago Sanitary and Ship Canal in order to keep several species of invasive Asian carp out of the lakes. These fast-growing planktivorous fish have heavily colonized the Mississippi and Illinois river systems. 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, as well as drastic unprecedented changes in
5856-463: The Great Lakes accessible to ocean-going vessels, shifts in shipping to wider ocean-going container ships —which do not fit through the locks on these routes—have 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 within
5978-459: The Great Lakes during mid-summer; these Mesoscale convective complexes or MCCs can cause damage to wide swaths of forest and shatter glass in city buildings. These storms mainly occur during the night, and the systems sometimes have small embedded tornadoes, but more often straight-line winds accompanied by intense lightning. Historically, the Great Lakes, in addition to their lake ecology , were surrounded by various forest ecoregions (except in
6100-441: The Great Lakes each year. Plastics in the water break up into very small particles known as microplastics . Microplastics can also come from synthetic clothing washed down our drains. Plastic waste found in the lakes include single-use plastics , plastics used in packaging, takeout containers as well as pre-production pellets produced by plastics industry . High concentrations of microplastics were discovered in 100 percent of
6222-438: The Great Lakes region include: Plant lists include: Logging of the extensive forests in the Great Lakes region removed riparian and adjacent tree cover over rivers and streams, which provide shade, moderating water temperatures in fish spawning grounds. Removal of trees also destabilized the soil, with greater volumes washed into stream beds causing siltation of gravel beds, and more frequent flooding. Running cut logs down
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#17327805674806344-561: The Great Lakes. A number of self-operating floating devices called Seabin, were put in the Great Lakes to capture plastic trash as part of the Great Lakes Plastic Cleanup project. The project captured 74,000 pieces of trash using this technology between 2020 and 2021; however, it does not claim to catch up with 22 million pounds (10.0 kt) of plastic that ends up in Great Lakes every year. The production, consumption, and throwing away of plastics seems to remain
6466-495: The Niles Cone Basin for total dissolved solids and other parameters. (California, 2001) This Alameda County, California –related article is a stub . You can help Misplaced Pages by expanding it . Groundwater Groundwater is the water present beneath Earth 's surface in rock and soil pore spaces and in the fractures of rock formations . About 30 percent of all readily available fresh water in
6588-509: The Straits of Mackinac. The straits are five miles (8 km) wide and 120 feet (37 m) deep; the water levels rise and fall together, and the flow between Michigan and Huron frequently reverses direction. 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
6710-427: The U.S. A variety of steps taken to process industrial and municipal pollution discharges into the system greatly improved water quality by the 1980s, and Lake Erie in particular is significantly cleaner. Discharge of toxic substances has been sharply reduced. Federal and state regulations control substances like PCBs . The first of 43 " Great Lakes Areas of Concern " to be formally "de-listed" through successful cleanup
6832-561: The age of groundwater obtained from different parts of the Great Artesian Basin, hydrogeologists have found it increases in age across the basin. Where water recharges the aquifers along the Eastern Divide , ages are young. As groundwater flows westward across the continent, it increases in age, with the oldest groundwater occurring in the western parts. This means that in order to have travelled almost 1000 km from
6954-495: The air in summer, then slowly radiate that heat in autumn. They protect against frost during transitional weather and keep the summertime temperatures cooler than further inland. This effect can be very localized and overridden by offshore wind patterns. This temperature buffering produces areas known as " fruit belts ", where fruit can be produced that is typically grown much farther south. For instance, western Michigan has apple orchards, and cherry orchards are cultivated adjacent to
7076-459: The anti-depressant drugs pass out of human bodies and through sanitation systems into the Great Lakes, this has resulted in fish in the Great Lakes with twenty times the level of anti-depressants in their brains than what is in the water, leading to the fish being exceedingly happy and hence less risk-averse, to the extent of damaging the fish populations. Researchers have found that more than 22 million pounds (10.0 kt) of plastic end up in
7198-405: The aquifer reduces the water pressure in the confining layer, causing it to compress from the weight of overlying geologic materials. In severe cases, this compression can be observed on the ground surface as subsidence . Unfortunately, much of the subsidence from groundwater extraction is permanent (elastic rebound is small). Thus, the subsidence is not only permanent, but the compressed aquifer has
7320-525: The aquifers are likely to run dry in 60 to 100 years. Groundwater provides critical freshwater supply, particularly in dry regions where surface water availability is limited. Globally, more than one-third of the water used originates from underground. In the mid-latitude arid and semi-arid regions lacking sufficient surface water supply from rivers and reservoirs, groundwater is critical for sustaining global ecology and meeting societal needs of drinking water and food production. The demand for groundwater
7442-432: The arrival of Europeans, and many more are threatened or endangered. Meanwhile, exotic and invasive species have also been introduced. While the organisms living on the bottom of shallow waters are similar to those found in smaller lakes, the deep waters contain organisms found only in deep, cold lakes of the northern latitudes. These include the delicate opossum shrimp (order mysida ), the deepwater scud (a crustacean of
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#17327805674807564-598: The atmosphere and fresh surface water (which have residence times from minutes to years). Deep groundwater (which is quite distant from the surface recharge) can take a very long time to complete its natural cycle. The Great Artesian Basin in central and eastern Australia is one of the largest confined aquifer systems in the world, extending for almost 2 million km . By analysing the trace elements in water sourced from deep underground, hydrogeologists have been able to determine that water extracted from these aquifers can be more than 1 million years old. By comparing
7686-510: The atmosphere through evapotranspiration , these salts are left behind. In irrigation districts, poor drainage of soils and surface aquifers can result in water tables' coming to the surface in low-lying areas. Major land degradation problems of soil salinity and waterlogging result, combined with increasing levels of salt in surface waters. As a consequence, major damage has occurred to local economies and environments. Aquifers in surface irrigated areas in semi-arid zones with reuse of
7808-694: The basins they had carved into the land, which then filled with meltwater. The lakes have been a major source for transportation, migration, trade, and fishing, serving as a habitat to many aquatic species in a region with much biodiversity . The surrounding region is called the Great Lakes region , which includes the Great Lakes Megalopolis . Major cities within the region include, on the American side, from east to west, Buffalo , Cleveland , Detroit , Chicago , and Milwaukee ; and, on
7930-427: The core of Great Lakes trash problem. Algae such as diatoms , along with other phytoplankton , are photosynthetic primary producers supporting the food web of the Great Lakes, and have been affected by global warming . The changes in the size or in the function of the primary producers may have a direct or an indirect impact on the food web. Photosynthesis carried out by diatoms constitutes about one fifth of
8052-491: The current population growth rate. Global groundwater depletion has been calculated to be between 100 and 300 km per year. This depletion is mainly caused by "expansion of irrigated agriculture in drylands ". The Asia-Pacific region is the largest groundwater abstractor in the world, containing seven out of the ten countries that extract most groundwater (Bangladesh, China, India, Indonesia, Iran, Pakistan and Turkey). These countries alone account for roughly 60% of
8174-779: The cyanobacteria ... will produce toxins", said Michael McKay, of the University of Windsor. Water quality testing was underway in August 2019. Until 1970, mercury was not listed as a harmful chemical, according to the United States Federal Water Quality Administration. In the 21st century, mercury has become more apparent in water tests. Mercury compounds have been used in paper mills to prevent slime from forming during their production, and chemical companies have used mercury to separate chlorine from brine solutions. Studies conducted by
8296-404: The extended period over which the damage occurs. The importance of groundwater to ecosystems is often overlooked, even by freshwater biologists and ecologists. Groundwaters sustain rivers, wetlands , and lakes , as well as subterranean ecosystems within karst or alluvial aquifers. Not all ecosystems need groundwater, of course. Some terrestrial ecosystems – for example, those of
8418-407: The extent, depth and thickness of water-bearing sediments and rocks. Before an investment is made in production wells, test wells may be drilled to measure the depths at which water is encountered and collect samples of soils, rock and water for laboratory analyses. Pumping tests can be performed in test wells to determine flow characteristics of the aquifer. The characteristics of aquifers vary with
8540-461: The fish that were studied by researchers from the Rochman Lab. About 50 million pounds (23 kt) of fish is harvested each year from Great Lakes which has raised concerns on how this might affect human health. Microscopic pieces of plastic have also been found in drinking water coming from Great Lakes. It is estimated that nearly 40 million people in the region rely on drinking water from
8662-443: The fish 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%. In the late 1960s, the various state and federal governments began stocking several species of salmonids, including the native lake trout as well as non-native chinook and coho salmon; by the 1980s, alewife populations had dropped drastically. The ruffe ,
8784-443: 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. The amount of raw sewage dumped into the waters was the primary focus of both the first Great Lakes Water Quality Agreement and federal laws passed in both countries during the 1970s. Implementation of secondary treatment of municipal sewage by major cities greatly reduced
8906-471: The five Great Lakes have long been called inland seas . Depending on how it is measured, by surface area, either Lake Superior or Lake Michigan–Huron is the second-largest lake in the world and the largest freshwater lake. Lake Michigan is the largest lake, by surface area, that is entirely within one country, the United States. The Great Lakes began to form at the end of the Last Glacial Period around 14,000 years ago, as retreating ice sheets exposed
9028-472: The geology and structure of the substrate and topography in which they occur. In general, the more productive aquifers occur in sedimentary geologic formations. By comparison, weathered and fractured crystalline rocks yield smaller quantities of groundwater in many environments. Unconsolidated to poorly cemented alluvial materials that have accumulated as valley -filling sediments in major river valleys and geologically subsiding structural basins are included among
9150-417: The glaciers "rebounded" as it was uncovered. Since the glaciers covered some areas longer than others, this glacial rebound occurred at different rates. The Great Lakes have a humid continental climate, Köppen climate classification Dfa (in southern areas) and Dfb (in northern parts) with varying influences from air masses from other regions including dry, cold Arctic systems, mild Pacific air masses from
9272-404: The globe includes canals redirecting surface water, groundwater pumping, and diverting water from dams. Aquifers are critically important in agriculture. Deep aquifers in arid areas have long been water sources for irrigation. A majority of extracted groundwater, 70%, is used for agricultural purposes. In India, 65% of the irrigation is from groundwater and about 90% of extracted groundwater
9394-416: The ground surface (within a couple of hundred metres) and have some recharge by fresh water. This recharge is typically from rivers or meteoric water (precipitation) that percolates into the aquifer through overlying unsaturated materials. In general, the irrigation of 20% of farming land (with various types of water sources) accounts for the production of 40% of food production. Irrigation techniques across
9516-410: The historical average level. Although "true tides—changes in water level caused by the gravitational forces of the sun and moon—do occur in a semi-diurnal (twice daily) pattern", such changes are quite small and generally obscured by other forces. The lake levels are affected primarily by changes in regional meteorology and climatology. The outflows from Lakes Superior and Ontario are regulated, while
9638-491: The ice sheet left behind a large amount of meltwater ( Lake Algonquin , Lake Chicago , Glacial Lake Iroquois , and Champlain Sea ) that filled up the basins that the glaciers had carved, thus creating the Great Lakes as they are today. 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
9760-560: The influence of continuous evaporation, the salt concentration of the aquifer water may increase continually and eventually cause an environmental problem. Great Lakes The Great Lakes ( French : Grands Lacs ), also called the Great Lakes of North America , are a series of large interconnected freshwater lakes spanning the Canada–United States border . The five lakes are Superior , Michigan , Huron , Erie , and Ontario . (Hydrologically, Michigan and Huron are
9882-554: 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 (66,000 long tons; 74,000 short tons) [147 million pounds]." By 1801, the New York Legislature found it necessary to pass regulations curtailing obstructions to
10004-612: The lake and causing blooms," said Michael McKay, executive director of the Great Lakes Institute for Environmental Research (GLIER) at the University of Windsor . The largest Lake Erie bloom to date occurred in 2015, exceeding the severity index at 10.5 and in 2011 at a 10. In early August 2019, satellite images depicted a bloom stretching up to 1,300 square kilometres on Lake Erie, with the heaviest concentration near Toledo, Ohio . A large bloom does not necessarily mean
10126-650: The lake shore as far north as the Grand Traverse Bay . Near Collingwood, Ontario , commercial fruit orchards, including a few wineries, exist near the shoreline of southern Nottawasaga Bay . The eastern shore of Lake Michigan and the southern shore of Lake Erie have many successful wineries because of the lakes' moderating effects, as do the large commercial fruit and wine growing areas of the Niagara Peninsula located between Lake Erie and Lake Ontario. A similar phenomenon allows wineries to flourish in
10248-538: The lakes has been observed since records began in 1918. The water level of Lake Michigan–Huron had remained fairly constant over the 20th century. Recent lake levels include record low levels in 2013 in Lakes Superior, Erie, and Michigan-Huron, followed by record high levels in 2020 in the same lakes. The water level in Lake Ontario has remained relatively constant in the same time period, hovering around
10370-470: The lakes' levels: diversion (the transfer of water to other watersheds) and consumption (substantially done today by the use of lake water to power and cool electric generation plants, resulting in evaporation). Outflows through the Chicago Sanitary and Ship Canal is more than balanced by artificial inflows via the Ogoki River and Long Lake/ Kenogami River diversions. Fluctuation of the water levels in
10492-458: The lakes. Only barges can access the Illinois Waterway system providing access to the Gulf of Mexico via the Mississippi River. Despite their vast size, large sections of the Great Lakes freeze over in winter, interrupting most shipping from January to March. Some icebreakers ply the lakes, keeping the shipping lanes open through other periods of ice on the lakes. The Great Lakes are connected by
10614-415: The lakes. The province of Ontario does not border Lake Michigan, and the state of Michigan does not border Lake Ontario. New York and Wisconsin's jurisdictions extend into two lakes, and each of the remaining states into one of the lakes. As 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
10736-640: The largest source of usable water storage in the United States , and California annually withdraws the largest amount of groundwater of all the states. Underground reservoirs contain far more water than the capacity of all surface reservoirs and lakes in the US, including the Great Lakes . Many municipal water supplies are derived solely from groundwater. Over 2 billion people rely on it as their primary water source worldwide. Human use of groundwater causes environmental problems. For example, polluted groundwater
10858-468: 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 current. Lakes Huron and Michigan are sometimes considered a single lake, called Lake Michigan–Huron, because they are one hydrological body of water connected by
10980-494: The launch of the bi-national Great Lakes Fishery Commission . 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
11102-518: The local hydrogeology , may draw in non-potable water or saltwater intrusion from hydraulically connected aquifers or surface water bodies. This can be a serious problem, especially in coastal areas and other areas where aquifer pumping is excessive. Subsidence occurs when too much water is pumped out from underground, deflating the space below the above-surface, and thus causing the ground to collapse. The result can look like craters on plots of land. This occurs because, in its natural equilibrium state,
11224-412: The most productive sources of groundwater. Fluid flows can be altered in different lithological settings by brittle deformation of rocks in fault zones ; the mechanisms by which this occurs are the subject of fault zone hydrogeology . Reliance on groundwater will only increase, mainly due to growing water demand by all sectors combined with increasing variation in rainfall patterns . Groundwater
11346-476: The natural migrations of Atlantic salmon from Lake Erie into their spawning channels. In the early 19th century, the government of Upper Canada 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, but enforcement remained difficult. On both sides of the Canada–United States border,
11468-671: The open deserts and similar arid environments – exist on irregular rainfall and the moisture it delivers to the soil, supplemented by moisture in the air. While there are other terrestrial ecosystems in more hospitable environments where groundwater plays no central role, groundwater is in fact fundamental to many of the world's major ecosystems. Water flows between groundwaters and surface waters. Most rivers, lakes, and wetlands are fed by, and (at other places or times) feed groundwater, to varying degrees. Groundwater feeds soil moisture through percolation, and many terrestrial vegetation communities depend directly on either groundwater or
11590-467: The order amphipoda ), two types of copepods , and the deepwater sculpin (a spiny, large-headed fish). The Great Lakes are an important source of fishing . Early European settlers were astounded by both the variety and quantity of fish; there were 150 different species in the Great Lakes. Throughout history, fish populations were the early indicator of the condition of the Lakes and have remained one of
11712-470: The other two thirds. Groundwater provides drinking water to at least 50% of the global population. About 2.5 billion people depend solely on groundwater resources to satisfy their basic daily water needs. A similar estimate was published in 2021 which stated that "groundwater is estimated to supply between a quarter and a third of the world's annual freshwater withdrawals to meet agricultural, industrial and domestic demands." Global freshwater withdrawal
11834-516: The outflows of Michigan-Huron and Erie are not regulated at all. Ontario is the most tightly regulated, with its outflow controlled by the Moses-Saunders Power Dam , which explains its consistent historical levels. The Great Lakes contain 21% of the world's surface fresh water: 5,472 cubic miles (22,810 km ), or 6.0×10 U.S. gallons, that is 6 quadrillion U.S. gallons, (2.3×10 liters). The lakes contain about 84% of
11956-683: The percolated soil moisture above the aquifer for at least part of each year. Hyporheic zones (the mixing zone of streamwater and groundwater) and riparian zones are examples of ecotones largely or totally dependent on groundwater. A 2021 study found that of ~39 million investigated groundwater wells 6-20% are at high risk of running dry if local groundwater levels decline by a few meters, or – as with many areas and possibly more than half of major aquifers – continue to decline. Fresh-water aquifers, especially those with limited recharge by snow or rain, also known as meteoric water , can be over-exploited and depending on
12078-516: The proliferation of dams and impoundments have multiplied, necessitating more regulatory efforts. Concerns by the mid-19th century included obstructions in the rivers which prevented salmon and lake sturgeon from reaching their spawning grounds. The Wisconsin Fisheries Commission noted a reduction of roughly 25% in general fish harvests by 1875. The states have removed dams from rivers where necessary. Overfishing has been cited as
12200-428: The routine discharge of untreated sewage during the 1970s and 1980s. The International Joint Commission in 2009 summarized the change: "Since the early 1970s, the level of treatment to reduce pollution from waste water discharges to the Great Lakes has improved considerably. This is a result of significant expenditures to date on both infrastructure and technology, and robust regulatory systems that have proven to be, on
12322-423: The same terms as surface water : inputs, outputs and storage. The natural input to groundwater is seepage from surface water. The natural outputs from groundwater are springs and seepage to the oceans. Due to its slow rate of turnover, groundwater storage is generally much larger (in volume) compared to inputs than it is for surface water. This difference makes it easy for humans to use groundwater unsustainably for
12444-436: The shoreline of all the lakes would cover a distance roughly equivalent to travelling half-way around the world at the equator. A notable modern phenomenon is the formation of ice volcanoes over the lakes during wintertime. Storm-generated waves carve the lakes' ice sheet and create conical mounds through the eruption of water and slush. The process is only well-documented in the Great Lakes, and has been credited with sparing
12566-416: The source of recharge in 1 million years, the groundwater flowing through the Great Artesian Basin travels at an average rate of about 1 metre per year. Groundwater recharge or deep drainage or deep percolation is a hydrologic process, where water moves downward from surface water to groundwater. Recharge is the primary method through which water enters an aquifer . This process usually occurs in
12688-602: The southern shorelines from worse rocky erosion. It has been estimated that the foundational geology that created the conditions shaping the present day upper Great Lakes was laid from 1.1 to 1.2 billion years ago, 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
12810-497: The subsurface. The high specific heat capacity of water and the insulating effect of soil and rock can mitigate the effects of climate and maintain groundwater at a relatively steady temperature . In some places where groundwater temperatures are maintained by this effect at about 10 °C (50 °F), groundwater can be used for controlling the temperature inside structures at the surface. For example, during hot weather relatively cool groundwater can be pumped through radiators in
12932-414: The surface freshwater of North America; if the water were evenly distributed over the entire continent's land area, it would reach a depth of 5 feet (1.5 meters). This is enough water to cover the 48 contiguous U.S. states to a uniform depth of 9.5 feet (2.9 m). 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
13054-562: The treatment plant, are temporarily overwhelmed by heavy rainstorms. Local sewage treatment authorities then must release untreated effluent, a mix of rainwater and sewage, into local water bodies. While enormous public investments such as the Deep Tunnel projects in Chicago and Milwaukee have greatly reduced the frequency and volume of these events, they have not been eliminated. The number of such overflow events in Ontario, for example,
13176-532: The tributary rivers into the Great Lakes also dislocated sediments. In 1884, the New York Fish Commission determined that the dumping of sawmill waste (chips and sawdust) had impacted fish populations. The first U.S. Clean Water Act , passed by a Congressional override after being vetoed by U.S. President Richard Nixon in 1972, was a key piece of legislation, along with the bi-national Great Lakes Water Quality Agreement signed by Canada and
13298-408: The unavoidable irrigation water losses percolating down into the underground by supplemental irrigation from wells run the risk of salination . Surface irrigation water normally contains salts in the order of 0.5 g/L or more and the annual irrigation requirement is in the order of 10,000 m /ha or more so the annual import of salt is in the order of 5,000 kg/ha or more. Under
13420-416: The warmer and shallower portions of the system such as Lake Erie, Saginaw Bay , Green Bay , and the southernmost portion of Lake Michigan. By the mid-1980s, most jurisdictions bordering the Great Lakes had controlled phosphate detergents . Blue-green algae, or cyanobacteria blooms, have been problematic on Lake Erie since 2011. "Not enough is being done to stop fertilizer and phosphorus from getting into
13542-430: The west pick up the air and moisture from the lake surface, which is slightly warmer in relation to the cold surface winds above. As the slightly warmer, moist air passes over the colder land surface, the moisture often produces concentrated, heavy snowfall that sets up in bands or "streamers". This is similar to the effect of warmer air dropping snow as it passes over mountain ranges. During freezing weather with high winds,
13664-427: The west, and warm, wet tropical systems from the south and the Gulf of Mexico. The lakes have a moderating effect on the climate; they can also increase precipitation totals and produce lake effect snowfall . The Great Lakes can have an effect on regional weather called lake-effect snow , which is sometimes very localized. Even late in winter, the lakes often have no icepack in the middle. The prevailing winds from
13786-480: The whole, quite effective." The commission reported that all urban sewage treatment systems on the U.S. side of the lakes had implemented secondary treatment, as had all on the Canadian side except for five small systems. Though contrary to federal laws in both countries, those treatment system upgrades have not yet eliminated combined sewer overflow events. This describes when older sewerage systems, which combine storm water with sewage into single sewers heading to
13908-441: The world is groundwater. A unit of rock or an unconsolidated deposit is called an aquifer when it can yield a usable quantity of water. The depth at which soil pore spaces or fractures and voids in rock become completely saturated with water is called the water table . Groundwater is recharged from the surface; it may discharge from the surface naturally at springs and seeps , and can form oases or wetlands . Groundwater
14030-519: The world's liquid fresh water is groundwater. Global groundwater storage is roughly equal to the total amount of freshwater stored in the snow and ice pack, including the north and south poles. This makes it an important resource that can act as a natural storage that can buffer against shortages of surface water , as in during times of drought . The volume of groundwater in an aquifer can be estimated by measuring water levels in local wells and by examining geologic records from well-drilling to determine
14152-472: The world's surface fresh water by volume. The total surface is 94,250 square miles (244,106 km ), and the total volume (measured at the low water datum) is 5,439 cubic miles (22,671 km ), slightly less than the volume of Lake Baikal (5,666 cu mi or 23,615 km , 22–23% of the world's surface fresh water). Because of their sea-like characteristics, such as rolling waves, sustained winds, strong currents, great depths, and distant horizons,
14274-420: The world's total groundwater withdrawal. Groundwater may or may not be a safe water source. In fact, there is considerable uncertainty with groundwater in different hydrogeologic contexts: the widespread presence of contaminants such as arsenic , fluoride and salinity can reduce the suitability of groundwater as a drinking water source. Arsenic and fluoride have been considered as priority contaminants at
14396-567: The world. The second-largest island is Isle Royale in Lake Superior. Both of these islands are large enough to contain multiple lakes themselves—for instance, Manitoulin Island's Lake Manitou is the world's largest lake on a freshwater island. Some of these lakes even have their own islands, like Treasure Island in Lake Mindemoya in Manitoulin Island. The Great Lakes also have several peninsulas between them, including
14518-523: The zooplankton community of the lake. Scientists understand that the micro-aquatic life of the lakes is abundant but know very little about some of the most plentiful microbes and their environmental effects in the Great Lakes. Although a drop of lake water may contain 1 million bacteria cells and 10 million viruses , only since 2012 has there been a long-term study of the lakes' micro-organisms. Between 2012 and 2019 more than 160 new species have been discovered. Native habitats and ecoregions in
14640-558: Was Ontario's Collingwood Harbour in 1994; Ontario's Severn Sound followed in 2003. Presque Isle Bay in Pennsylvania is formally listed as in recovery, as is Ontario's Spanish Harbour. Dozens of other Areas of Concern have received partial cleanups such as the Rouge River (Michigan) and Waukegan Harbor (Illinois). Phosphate detergents were historically a major source of nutrient to the Great Lakes algae blooms in particular in
14762-517: Was eliminated as the mussels were harvested for use as buttons by early Great Lakes entrepreneurs. The Great Lakes: An Environmental Atlas and Resource Book (1972) notes: "Only pockets remain of the once large commercial fishery." Water quality improvements realized during the 1970s and 1980s, combined with successful salmonid stocking programs, have enabled the growth of a large recreational fishery. The last commercial fisherman left Milwaukee in 2011 because of overfishing and anthropogenic changes to
14884-402: Was probably around 600 km per year in 1900 and increased to 3,880 km per year in 2017. The rate of increase was especially high (around 3% per year) during the period 1950–1980, partly due to a higher population growth rate, and partly to rapidly increasing groundwater development, particularly for irrigation. The rate of increase is (as per 2022) approximately 1% per year, in tune with
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