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36-413: The name Brakpan comes from a small pan on a farm called Weltevreden, which was filled with very brackish water and was probably referred to as the "brakpan," and it was near this pan that the first settlement started. In 1888, a coal seam was discovered and a coal mine under the name of Brakpan Collieries was started. When a railway line was constructed from Germiston to Springs , Brakpan became one of

72-472: A few miles west of London marks the boundary between the tidal and non-tidal parts of the Thames, although it is still considered a freshwater river about as far east as Battersea insofar as the average salinity is very low and the fish fauna consists predominantly of freshwater species such as roach , dace , carp , perch , and pike . The Thames Estuary becomes brackish between Battersea and Gravesend , and

108-509: A huge casino and entertainment complex, Carnival City, which opened the town to tourists and provided much-needed jobs for the people. The first activity which drew people to the area was the British coal mining in 1888 and the large coal powered power station also built by the British. A tram line to Johannesburg was built at this time to service the power station. The Main Reef Road (today part of

144-610: A natural defense against hurricane and tsunami damage in particular. The Sundarbans and Bhitarkanika Mangroves are two of the large mangrove forests in the world, both on the coast of the Bay of Bengal . Some seas and lakes are brackish. The Baltic Sea is a brackish sea adjoining the North Sea . Originally the Eridanos river system prior to the Pleistocene , since then it has been flooded by

180-459: A salt concentration greater than 30‰ is considered saline . See the salinity table from the Misplaced Pages salinity article . Brackish water condition commonly occurs when fresh water meets seawater. In fact, the most extensive brackish water habitats worldwide are estuaries , where a river meets the sea. The River Thames flowing through London is a classic river estuary. The town of Teddington

216-526: A species only found in deep water in the Baltic, while pike are confined to the less saline surface waters. The Caspian Sea is the world's largest lake and contains brackish water with a salinity about one-third that of normal seawater. The Caspian is famous for its peculiar animal fauna, including one of the few non-marine seals (the Caspian seal ) and the great sturgeons , a major source of caviar . Hudson Bay

252-544: Is a brackish marginal sea of the Arctic Ocean , it remains brackish due its limited connections to the open ocean, very high levels freshwater surface runoff input from the large Hudson Bay drainage basin , and low rate of evaporation due to being completely covered in ice for over half the year. In the Black Sea the surface water is brackish with an average salinity of about 17–18 parts per thousand compared to 30 to 40 for

288-490: Is associated with the melting of ice in the time since the last glacial maximum . Dating of groundwater relies on measuring concentrations of certain stable isotopes, including H ( tritium ) and O ( "heavy" oxygen ), and comparing values with known concentrations of the geologic past . Fossil water can potentially dissolve and absorb a number of ions from its host rock. Salinity in groundwater can be higher than seawater. In some cases, some form of treatment

324-765: Is commonly used as cooling water for power generation and in a variety of ways in the mining, oil, and gas industries. Once desalinated it can also be used for agriculture, livestock, and municipal uses. Brackish water can be treated using reverse osmosis , electrodialysis , and other filtration processes. Fossil water Fossil water , fossil groundwater , or paleowater is an ancient body of water that has been contained in some undisturbed space, typically groundwater in an aquifer , for millennia. Other types of fossil water can include subglacial lakes , such as Antarctica 's Lake Vostok . UNESCO defines fossil groundwater as "water that infiltrated usually millennia ago and often under climatic conditions different from

360-475: Is extracted from these aquifers for many human purposes, notably, agriculture , industry , and consumption. In arid regions , some aquifers containing available and usable water receive little to no significant recharge, effectively making groundwater in those aquifers a non-renewable resource . Extraction rates greater than recharge rates result in lowering of the water table and can lead to groundwater depletion . Extraction of non-renewable groundwater resources

396-472: Is found in arid or semi-arid regions where the climate was significantly more humid in recent geologic history. In some semi-arid regions, the majority of precipitation evaporates before it can infiltrate and result in any significant aquifer recharge . Most fossil groundwater has been estimated to have originally infiltrated within the Holocene and Pleistocene (10,000–40,000 years ago). Some fossil groundwater

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432-399: Is in central southern Africa (Botswana, Namibia, and South Africa). Geology of the area includes significant karst formations. Most of the precipitation in the region evaporates before it can contribute to significant recharge of the aquifers below. Whether or not the region's aquifers receive any significant recharge has long been the subject of debate and research. In the northern region of

468-433: Is located in northeastern Africa, under the nations of Sudan, Libya, Egypt, and Chad, covering about 2,000,000 km . It is largely composed of many hydraulically interconnected sandstone aquifers. Some parts of the system are considered to be confined, if somewhat leaky, due to impermeable layers such as marine shales. The water was deposited between 4,000 and 20,000 years ago, varying by specific locality. The water in

504-410: Is referred to as groundwater "mining" because of their finite nature. Aquifers are typically composed of semi- porous rock or unconsolidated material whose pore space has been filled with water. In the relatively rare cases of confined aquifers, an impermeable geologic layer (e.g. clay or calcrete ) encloses an aquifer, isolating the water within, sometimes for millennia. More commonly, fossil water

540-507: Is required to make these waters suitable for human use. Saline fossil aquifers can also store significant quantities of oil and natural gas . The Ogallala or High Plains Aquifer sits under 450,000 km of 8 states of the United States of America. It is one of the largest freshwater deposits in the world. The aquifer is composed of unconsolidated alluvial deposits. Groundwater in this aquifer has been dated to have been deposited in

576-672: Is the mangrove swamp or mangal . Many, though not all, mangrove swamps fringe estuaries and lagoons where the salinity changes with each tide. Among the most specialised residents of mangrove forests are mudskippers , fish that forage for food on land, and archer fish , perch-like fish that "spit" at insects and other small animals living in the trees, knocking them into the water where they can be eaten. Like estuaries, mangrove swamps are extremely important breeding grounds for many fish, with species such as snappers , halfbeaks , and tarpon spawning or maturing among them. Besides fish, numerous other animals use mangroves, including such species as

612-504: The saltwater crocodile , American crocodile , proboscis monkey , diamondback terrapin , and the crab-eating frog , Fejervarya cancrivora (formerly Rana cancrivora ). Mangroves represent important nesting sites for numerous birds groups such as herons, storks, spoonbills, ibises, kingfishers, shorebirds and seabirds. Although often plagued with mosquitoes and other insects that make them unpleasant for humans, mangrove swamps are very important buffer zones between land and sea, and are

648-500: The R29 ) linked Brakpan to all the other mining towns in the Witwatersrand . Brakpan was a suburb of Benoni from 1914–1919, when it was granted municipal status. The Brakpan miners were involved in the miners' strike of 1922 . The town has gradually lost its importance as a gold mining area as the surrounding mines suffered from low yield over high cost. Many British residents emigrated during

684-638: The M46 holds several names such as Airport Road, Athlone Avenue, Voortrekker Road, Prince George Avenue and Olympia Road. Voortrekker Road is the main street through the Brakpan CBD . Brackish Brackish water , sometimes termed brack water , is water occurring in a natural environment that has more salinity than freshwater , but not as much as seawater . It may result from mixing seawater (salt water) and fresh water together, as in estuaries , or it may occur in brackish fossil aquifers . The word comes from

720-527: The Middle Dutch root brak . Certain human activities can produce brackish water, in particular civil engineering projects such as dikes and the flooding of coastal marshland to produce brackish water pools for freshwater prawn farming . Brackish water is also the primary waste product of the salinity gradient power process. Because brackish water is hostile to the growth of most terrestrial plant species, without appropriate management it can be damaging to

756-660: The N17 gives access to the town via the exits at Heidelberg Road, Denne Road and Ergo Road. Running parallel to the N17, the R554 (Elsburg Road; Springs Road) leads south-westwards to Alberton – 34 km and eastwards to Springs. The R23 (Heidelberg Road) skirts Brakpan to the west, leading northwards to Benoni and southwards to Heidelberg – 35 km. The M45 (Prince George Avenue) leads north-westwards to Benoni and southwards to KwaThema . The M46 leads westwards from Brakpan to Boksburg and eastwards to Springs. In passing through Brakpan,

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792-479: The North Sea but still receives so much freshwater from the adjacent lands that the water is brackish. As seawater is denser, the water in the Baltic is stratified, with seawater at the bottom and freshwater at the top. Limited mixing occurs because of the lack of tides and storms, with the result that the fish fauna at the surface is freshwater in composition while that lower down is more marine. Cod are an example of

828-578: The Nubian Sandstone Aquifer System is of high importance to the people living above it, and has been for millennia. In modern times, as demand increases, avoiding rapid depletion and international conflict will depend on careful cross-boundary monitoring and planning. Libya and Egypt are currently planning development projects to withdraw significant amounts of the aquifer's fossil water for use. Other fossil aquifers have been identified throughout Northern Africa as well. The Kalahari Desert

864-520: The Thames Estuary for this purpose. Estuaries are also commonly used as fishing grounds and as places for fish farming or ranching. For example, Atlantic salmon farms are often located in estuaries, although this has caused controversy, because in doing so, fish farmers expose migrating wild fish to large numbers of external parasites such as sea lice that escape from the pens the farmed fish are kept in. Another important brackish water habitat

900-736: The apartheid era leaving a vacuum in the town which was filled by mostly Afrikaner farmers who had lost interest in farming. Situated between Springs and Benoni , it forms part of the Ekurhuleni Metro . Brakpan is often used in memes in South African online communities, often depicted in a way similar to Southern US locations in US centric memes. Brakpan is mainly located along the N17 highway leading eastwards from Boksburg and Johannesburg to Springs and Secunda (102 km). In passing through Brakpan,

936-455: The changes in salinity. Salmon are anadromous, meaning they live in the sea but ascend rivers to spawn; eels are catadromous, living in rivers and streams, but returning to the sea to breed. Besides the species that migrate through estuaries, there are many other fish that use them as "nursery grounds" for spawning or as places young fish can feed and grow before moving elsewhere. Herring and plaice are two commercially important species that use

972-406: The diversity of freshwater fish species present is smaller, primarily roach and dace; euryhaline marine species such as flounder , European seabass , mullet , and smelt become much more common. Further east, the salinity increases and the freshwater fish species are completely replaced by euryhaline marine ones, until the river reaches Gravesend, at which point conditions become fully marine and

1008-490: The environment (see article on shrimp farms ). Technically, brackish water contains between 0.5 and 30 grams of salt per litre—more often expressed as 0.5 to 30 parts per thousand (‰), which is a specific gravity of between 1.0004 and 1.0226. Thus, brackish covers a range of salinity regimes and is not considered a precisely defined condition. It is characteristic of many brackish surface waters that their salinity can vary considerably over space or time. Water with

1044-531: The field are developing quickly and the scientific knowledge base is growing. In the cases of many aquifers, research is lacking or disputed as to the age of the water and the behavior of the water inside the aquifer. Large, prolific aquifers (notably the Nubian Sandstone Aquifer System and the Ogallala Aquifer ) containing fossil water are of significant socio-economic value. Fossil water

1080-548: The fish fauna resembles that of the adjacent North Sea and includes both euryhaline and stenohaline marine species. A similar pattern of replacement can be observed with the aquatic plants and invertebrates living in the river. This type of ecological succession from freshwater to marine ecosystem is typical of river estuaries. River estuaries form important staging points during the migration of anadromous and catadromous fish species, such as salmon , shad and eels , giving them time to form social groups and to adjust to

1116-566: The humid time following the last glacial maximum. In much of the aquifer's area, an impermeable layer of calcrete prevents precipitation from infiltrating. In other regions of the aquifer, some relatively small rates of recharge have been measured. The aquifer supplies water for the many people who live above it and for widespread agricultural uses. In many areas, the water table has dropped drastically due to heavy extraction. Depletion rates are not stabilizing; in fact, they have been increasing in recent decades. The Nubian Sandstone Aquifer System

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1152-537: The oceans. The deep, anoxic water of the Black Sea originates from warm, salty water of the Mediterranean . Lake Texoma , a reservoir on the border between the U.S. states of Texas and Oklahoma , is a rare example of a brackish lake that is neither part of an endorheic basin nor a direct arm of the ocean, though its salinity is considerably lower than that of the other bodies of water mentioned here. The reservoir

1188-493: The present, and that has been stored underground since that time." Determining the time since water infiltrated usually involves analyzing isotopic signatures . Determining "fossil" status—whether or not that particular water has occupied that particular space since the distant past—involves modeling the flow, recharge , and losses of aquifers, which can involve significant uncertainty. Some aquifers are hundreds of meters deep and underlie vast areas of land. Research techniques in

1224-453: The pyramids of Egypt except the Pyramid of Cheops . From 1905 the village began to grow rapidly, remaining a suburb of Benoni until 1912 when it was granted the status of a municipality and proclaimed as a town. Brakpan's central position makes it a good distribution centre for industry, especially engineering works and foundries. In the late 1990s the municipality approved the construction of

1260-408: The stations along the route. With gold fever running high on the Witwatersrand in the early years of the twentieth century, it was not long before gold was discovered. In 1905, Brakpan Mines Company sunk its first two gold mining shafts. One of its claims to fame was that it had the highest mine dump in the world at that time, 120 metres (390 ft) above ground level. This was higher than any of

1296-510: Was created by the damming of the Red River of the South , which (along with several of its tributaries) receives large amounts of salt from natural seepage from buried deposits in the upstream region. The salinity is high enough that striped bass , a fish normally found only in salt water, has self-sustaining populations in the lake. Brackish water is being used by humans in many different sectors. It

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