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62-601: Its main objective is to reduce erosion, which includes future sea level rise and storm surges. On the Lagos Bar Beach, coastal erosion has long been an issue, happening at a rate of 30 m year in particular. Wave tides, littoral movements, and sediment characteristics are examples of natural causes. Around 1960, man began adding nourishments to the Bar Beach in an effort to stop the significant loss of beach width caused by erosion. Despite being fed with enormous amounts of material,

124-402: A dragline . This technique is often used in excavation of bay mud . Most of these dredges are crane barges with spuds , steel piles that can be lowered and raised to position the dredge. A backhoe/dipper dredger has a backhoe like on some excavators . A crude but usable backhoe dredger can be made by mounting a land-type backhoe excavator on a pontoon . The six largest backhoe dredgers in

186-482: A capacity of 6,000 cubic metres per hour (59,000 cu ft/ks). An even larger dredger, retired in 1980, was the U.S. Army Corps of Engineers Essayons , which was 525.17 feet (160.07 m) long. The Mallard II , a clamshell dredger that maintains levees in San Francisco Bay , has operated continuously since being built in 1936. Dredgers are often equipped with dredge monitoring software to help

248-439: A few different types of dredge hoses that differ in terms of working pressure, float-ability, armored or not etc. Suction hoses, discharge armored hoses and self-floating hoses are some of the popular types engineered for transporting and discharging dredge materials. Some even had the pipes or hoses customised to exact dredging needs etc. Other times, it is pumped into barges (also called scows ), which deposit it elsewhere while

310-478: A long tube like some vacuum cleaners but on a larger scale. A plain suction dredger has no tool at the end of the suction pipe to disturb the material. A trailing suction hopper dredger (TSHD) trails its suction pipe when working. The pipe, which is fitted with a dredge drag head , loads the dredge spoil into one or more hoppers in the vessel. When the hoppers are full, the TSHD sails to a disposal area and either dumps

372-496: A mass migration of businesses over the last twenty-five years. Today, Victoria Island is one of Nigeria's busiest centres of banking and commerce, with most major Nigerian and international corporations headquartered on the Island. The Island has continued to rapidly develop and along with Ikoyi , is a favourite spot for Nigerians and foreigners to live and play. However, the influx of banks and other commercial ventures has changed

434-496: A process known as dewatering. Current dewatering techniques employ either centrifuges, geotube containers, large textile based filters or polymer flocculant /congealant based apparatus. In many projects, slurry dewatering is performed in large inland settling pits, although this is becoming less and less common as mechanical dewatering techniques continue to improve. Similarly, many groups (most notable in east Asia) are performing research towards utilizing dewatered sediments for

496-681: A separate municipality. It will have an offshore banking zone and permit investors to transfer money freely. When the city is finished, it will have 3,000 buildings and 400,000 homes for residential, business, financial, and tourist lodging purposes. Ten districts will make up the city, including: The cost of a plot of land is dependent on its size and location. Land is sold per m. Plot sizes in Phases 1 and 2 start from approximately 2,200 m and prices per square meter within this phase start from $ 1,150. In Phase 3, land within this phase starts from approximately 1,200 m mainly for low-rise residential houses where

558-411: A shipping channel through coral reefs . A bucket dredger is equipped with a bucket dredge, which is a device that picks up sediment by mechanical means, often with many circulating buckets attached to a wheel or chain . A grab dredger picks up seabed material with a clam shell bucket , which hangs from an onboard crane or a crane barge , or is carried by a hydraulic arm, or is mounted like on

620-515: Is a bar or blade which is pulled over the seabed behind any suitable ship or boat. It has an effect similar to that of a bulldozer on land. The chain-operated steam dredger Bertha , built in 1844 to a design by Brunel and as of 2009 was the oldest operational steam vessel in Britain, was of this type. This is an early type of dredger which was formerly used in shallow water in the Netherlands. It

682-475: Is also being criticized for failing to involve the people in the project. In August 2012, the Atlantic Ocean surged and overflowed its banks, sweeping 16 people into the Atlantic Ocean, killing several, and flooding Kuramo Beach , Victoria Island and other areas. According to an environmental expert, "the ocean surge occurred as a result of the failure of the contractors handling the sandfilling activities of

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744-479: Is expected to rise as the next generation of property on the African continent; having a total of 10 districts, spread across a land area of approximately 10 square kilometres (3.9 sq mi), the city will satisfy needs for financial, commercial, residential and tourist accommodations. Eko Atlantic development is being carried out as a public–private partnership (PPP) with private companies and investors providing

806-424: Is mainly used in harbours and other shallow water. Excavator dredge attachments The excavator dredge attachment uses the characteristics of cutter-suction dredgers, consisting of cutter heads and a suction pump for transferring material. These hydraulic attachments mount onto the boom arm of an excavator allowing an operator to maneuver the attachment along the shoreline and in shallow water for dredging. This

868-567: Is part of the Silverbird cinema chain and should not be confused with the cinemas of the same name in other parts of Lagos. Victoria Island hosts most of the diplomatic presence in Lagos, many of which were previously the embassies to Nigeria prior to the move of the capital to Abuja . The now consulates , embassy branch offices, or Deputy High Commissions on Victoria Island include Benin, Brazil, Canada, China, Germany, India, Indonesia, Italy, Lebanon,

930-409: Is the excavation of material from a water environment. Possible reasons for dredging include improving existing water features ; reshaping land and water features to alter drainage , navigability , and commercial use; constructing dams , dikes , and other controls for streams and shorelines; and recovering valuable mineral deposits or marine life having commercial value. In all but a few situations

992-410: Is usually sucked up by a wear-resistant centrifugal pump and discharged either through a pipe line or to a barge. Cutter-suction dredgers are most often used in geological areas consisting of hard surface materials (for example gravel deposits or surface bedrock) where a standard suction dredger would be ineffective. They can, if sufficiently powerful, be used instead of underwater blasting. As of 2024,

1054-479: The Leiv Eriksson are: 46,000 cubic metre hopper and a design dredging depth of 155 m. Next largest is HAM 318 ( Van Oord ) with its 37,293 cubic metre hopper and a maximum dredging depth of 101 m. A cutter-suction dredger's (CSD) suction tube has a cutting mechanism at the suction inlet. The cutting mechanism loosens the bed material and transports it to the suction mouth. The dredged material

1116-675: The Chagoury group , was specifically created to undertake the development. Testing of the sea defence system took place at the DHI Institute in Copenhagen , Denmark , where models were successfully tested for one-in-a-hundred-year ocean surges , and one-in-120-year, one-in-150-year and one-in-1,000-year storms. Eko Atlantic will satisfy needs for financial, commercial, residential and tourist accommodations, with infrastructure in line with modern and environmental standards. These standards will offer

1178-699: The Lagos City Marathon and Copa Lagos. Eko Atlantic City has secured an EDGE certification from the International Finance Corporation (IFC), a member of the World Bank Group . The Eko Atlantic project has been criticized by residents living nearby, who say that ongoing construction works have caused coastal erosion and ocean surges. Ocean water surges through living areas, flooding access roads and taking down electricity poles and forcing residents to relocate. The Lagos State Government

1240-581: The Lagos Lagoon . It is the main business and financial centre of Lagos State , Nigeria. Victoria Island is one of the most exclusive and expensive areas to reside in Lagos. The town and island lie within the boundaries of the Eti-Osa Local Government Area (LGA). A large part of the Island was originally part of jurisdiction of the Oniru chieftaincy family of Lagos with tenants inhabiting

1302-771: The Lagos State Government and its private sector partners on the Project, South Energyx, received the Clinton Global Initiative Commitment Certificate. In addition to providing a state-of-the-art business district for West Africa, the city aims to restore land lost to coastal erosion over the past century, offer a long-term solution to the erosion problem along Lagos' coastline, shield Victoria Island from ocean surge, and create job opportunities. Seven kilometers of revetment will also be built. The city will have its own bureaucracy and be regarded as

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1364-477: The Nile were channelled and wharfs built at the time of the pyramids (4000 BC), there was extensive harbour building in the eastern Mediterranean from 1000 BC and the disturbed sediment layers gives evidence of dredging. At Marseille , dredging phases are recorded from the third century BC onwards, the most extensive during the first century AD. The remains of three dredging boats have been unearthed; they were abandoned at

1426-518: The East Mole. A revetment with a length of around 8.4 km surrounds the newly recovered area to prevent erosion. Among other things, Royal Haskoning provides advisory services for Eko Atlantic City's marine construction. The city adjoins Victoria Island district of Lagos city , and the Phase 1 area of Lekki to the north, while the entire Western, eastern and southern borders is a coastline. Eko Atlantic

1488-463: The Island complained about this problem, leading the military Governor of the State, Raji Rasaki , to forcibly remove the residents on 14 July 1990, resulting in numerous injuries. Governor Rasaki and his armed security forces caused the eviction of as many as 300,000 residents, some of whom had legal title to their property. This new area established after the evictions was called Victoria Island Annex. It

1550-545: The Lagos-Calabar Coastal Highway, Nigeria’s biggest public infrastructure project. Discussions around the ownership of the coast; Eko Atlantic and Landmark's claim to this contentious and premium waterfront. Victoria Island (Nigeria) Victoria Island ( VI ) is an affluent area that encompasses a former island of the same name neighbouring Lagos Island , Ikoyi and the Lekki Peninsula by

1612-894: The Netherlands, Russia, South Africa, the United Kingdom, and the United States. The British International School Lagos , and the Lycée Français Louis Pasteur de Lagos are on Victoria Island. Also located on Victoria Island is the American International School of Lagos , 6°25′50″N 3°25′20″E  /  6.43056°N 3.42222°E  / 6.43056; 3.42222 See also: List of schools in Lagos See also: List of hospitals in Lagos See also: List of festivals in Lagos See also: Architecture of Lagos Dredger Dredging

1674-632: The Nigerian justice system, without success. In 2008, a human rights organization, Social and Economic Rights Action Centre (SERAC), filed a complaint with the African Commission on Human and Peoples' Rights on behalf of the Moroko people. Activists and displaced Maroko residents continue to hold Maroko Remembrance Day each year on 14 July. There are many galleries on Victoria Island. Guaranty Trust Bank and Access Bank plc have their headquarters on

1736-562: The beach continued to erode. The city of Lagos's expanding population is another issue, as it increases the need for space for residential, commercial, and recreational activities. The private project developer South Energyx Nigeria Ltd. (SENL) has started the Eko Atlantic City Development Project to address this space shortage as well as the land loss caused by the erosion of the Bar Beach. This project involves reclaiming 9 km² of ground in front of Bar Beach, just east of

1798-520: The beds of streams. During the renaissance Leonardo da Vinci drew a design for a drag dredger. Dredging machines have been used during the construction of the Suez Canal from the late 1800s to present day expansions and maintenance. The completion of the Panama Canal in 1914, the most expensive U.S. engineering project at the time, relied extensively on dredging. These operate by sucking through

1860-600: The bottom of the harbour during the first and second centuries AD. The Banu Musa brothers during the Muslim Golden Age in while working at the Bayt-Al-Hikmah (house of wisdom) in Baghdad, designed an original invention in their book named ‘ Book of Ingenious Devices ’, a grab machine that does not appear in any earlier Greek works. The grab they described was used to extract objects from underwater, and recover objects from

1922-577: The city's residents water, waste management, security and transportation systems. The city will also have an independent source of energy generated specifically for the city. Eko Atlantic is situated on land reclaimed from erosion and is protected by a coastal revetment designed by Royal Haskoning colloquially known as the Great Wall of Lagos, a planned 8.5 km long barrier constructed primarily of rock and faced with concrete accropode armour. The Eko Atlantic City project received global attention in 2009, as

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1984-605: The construction industry. Dredging is a four-part process: loosening the material, bringing the material to the surface (together extraction), transportation and disposal. The extract can be disposed of locally or transported by barge or in a liquid suspension in pipelines. Disposal can be to infill sites, or the material can be used constructively to replenish eroded sand that has been lost to coastal erosion , or constructively create sea-walls, building land or whole new landforms such as viable islands in coral atolls . Ancient authors refer to harbour dredging. The seven arms of

2046-465: The construction of a highway connecting Victoria Island to Epe. This activity, along with the rapid commercialization of Victoria Island, served to stimulate residential development along the Lekki-Epe corridor, starting with Lekki Phase 1. The area of the land bridge, composed of the former swampland, became a large slum called Maroko Town which housed many of the new migrants to Lagos State. Residents of

2108-492: The dredge continues its work. A number of vessels, notably in the UK and NW Europe de-water the hopper to dry the cargo to enable it to be discharged onto a quayside 'dry'. This is achieved principally using self discharge bucket wheel, drag scraper or excavator via conveyor systems. When contaminated (toxic) sediments are to be removed, or large volume inland disposal sites are unavailable, dredge slurries are reduced to dry solids via

2170-482: The dredge operator position the dredger and monitor the current dredge level. The monitoring software often uses Real Time Kinematic satellite navigation to accurately record where the machine has been operating and to what depth the machine has dredged to. In a "hopper dredger", the dredged materials end up in a large onboard hold called a "hopper." A suction hopper dredger is usually used for maintenance dredging. A hopper dredge usually has doors in its bottom to empty

2232-425: The dredged materials, but some dredges empty their hoppers by splitting the two-halves of their hulls on large hydraulic hinges. Either way, as the vessel dredges, excess water in the dredged materials is spilled off as the heavier solids settle to the bottom of the hopper. This excess water is returned to the sea to reduce weight and increase the amount of solid material (or slurry) that can be carried in one load. When

2294-487: The environment, including the following: The nature of dredging operations and possible environmental impacts requires that the activity often be closely regulated and requires comprehensive regional environmental impact assessments alongside continuous monitoring. For example, in the U.S., the Clean Water Act requires that any discharge of dredged or fill materials into "waters of the United States," including wetlands,

2356-550: The excavation is undertaken by a specialist floating plant , known as a dredger. Usually the main objectives of dredging is to recover material of value, or to create a greater depth of water. Dredging systems can either be shore-based, brought to a location based on barges , or built into purpose-built vessels. Dredging can have environmental impacts: it can disturb marine sediments , leading to both short- and long-term water pollution , damage or destroy seabed ecosystems , and can release legacy human-sourced toxins captured in

2418-519: The form of a scoop made of chain mesh, and are towed by a fishing boat . Clam-specific dredges can utilize hydraulic injection to target deeper into the sand. Dredging can be destructive to the seabed and some scallop dredging has been replaced by collecting via scuba diving . As of June 2018, the largest dredger in Asia is MV  Tian Kun Hao , a 140-metre (460 ft) long dredger constructed in China, with

2480-591: The formerly serene atmosphere of the Island. Longtime residents complain about the increase in traffic and influx of street traders who cater to local bank employees and businessmen. A new project being developed by the Chagoury Group includes the Eko Atlantic City , located next to Victoria Island. The project is being built on reclaimed land that has been lost to coastal erosion . The displaced former residents of Maroko Town have pursued redress within

2542-409: The funding, whilst the Lagos State Government (LASG) is a strategic partner, with the support of the federal government. The contractors are China Communications Construction Group LTD (CCCC), a company that works in the field of marine dredging and landfill operation. Consultants are Royal Haskoning (traffic and transport expertise) and ar+h Architects. South Energyx Nigeria Ltd., a subsidiary of

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2604-447: The hopper is filled with slurry , the dredger stops dredging and goes to a dump site and empties its hopper. Some hopper dredges are designed so they can also be emptied from above using pumps if dump sites are unavailable or if the dredge material is contaminated. Sometimes the slurry of dredgings and water is pumped straight into pipes which deposit it on nearby land. These pipes are also commonly known as dredge hoses , too. There are

2666-576: The island, Halliburton and IBM operate offices on Victoria Island. Akin Adesola Street and the Adeola Odeku Street that runs into it on Victoria Island are the hot spot in terms of Lagos' better nightclubs.[6] Travel vlogger Drew Binsky raves about the city's vibrant nightlife with its "swanky bars, rowdy clubs, chill lounges and beach parties." The Silverbird Galleria is a shopping and entertainment centre on upmarket Victoria Island. It

2728-471: The land prices are at $ 1,050. There is no maximum cap on the amount of land that can be purchased. Each plot of land can be used for a residential or commercial development or a mix of both as Eko Atlantic is designed to be a mixed-use city. The plots in Phases 1 and 2 have been created to accommodate mid to high-rise buildings. In Phase 3, some plots have been created to accommodate single residential dwellings and low-rise developments. As of May 2009, while

2790-533: The land. In 1948, the Lagos Executive Development Board paid 250,000 pounds as compensation for the land acquired from the Oniru family and an additional 150,000 pounds as compensation for the inhabitants and shrines destroyed. The inhabitants were later resettled at Maroko village . Victoria Island was originally surrounded entirely by water. It was bordered by the Atlantic Ocean on the south,

2852-469: The material could well suit the building industry, or could be used for beach nourishment. Dredging can disturb aquatic ecosystems , often with adverse impacts. In addition, dredge spoils may contain toxic chemicals that may have an adverse effect on the disposal area; furthermore, the process of dredging often dislodges chemicals residing in benthic substrates and injects them into the water column . Dredging can have numerous significant impacts on

2914-460: The material through doors in the hull or pumps the material out of the hoppers. Some dredges also self-offload using drag buckets and conveyors. As of 2008 the largest trailing suction hopper dredgers in the world were Jan De Nul 's Cristobal Colon (launched 4 July 2008 ) and her sister ship Leiv Eriksson (launched 4 September 2009 ). Main design specifications for the Cristobal Colon and

2976-462: The most powerful cutter-suction dredger in the world is DEME 's Spartacus , which entered service in 2021. The auger dredge system functions like a cutter suction dredger, but the cutting tool is a rotating Archimedean screw set at right angles to the suction pipe. Mud Cat invented the auger dredge in the 1970s. These use the Venturi effect of a concentrated high-speed stream of water to pull

3038-623: The mouth of the Lagos Lagoon on the West, the Five Cowrie Creek to the North, and swamps on the East. The colonial government began the process of filling in the eastern swamps to reduce mosquito breeding areas. This created a land bridge between Victoria Island and Lekki Peninsula ending its existence as a true island. After independence, successive state governments expanded this development, culminating in

3100-426: The nearby water, together with bed material, into a pipe. An airlift is a type of small suction dredge. It is sometimes used like other dredges. At other times, an airlift is handheld underwater by a diver . It works by blowing air into the pipe, and that air, being lighter than water, rises inside the pipe, dragging water with it. Some bucket dredgers and grab dredgers are powerful enough to rip out coral to make

3162-667: The production of concretes and construction block, although the high organic content (in many cases) of this material is a hindrance toward such ends. The proper management of contaminated sediments is a modern-day issue of significant concern. Because of a variety of maintenance activities, thousands of tonnes of contaminated sediment are dredged worldwide from commercial ports and other aquatic areas at high level of industrialization. Dredged material can be reused after appropriate decontamination. A variety of processes has been proposed and tested at different scales of application ( technologies for environmental remediation ). Once decontaminated,

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3224-407: The project was still in its dredging phase, about 3,000,000 cubic metres (3,900,000 cu yd) had been sand-filled and placed in the reclamation area, while about 35,000 tonnes of rock had been delivered to the site. In certain parts of Bar Beach, the land being reclaimed can already be seen. Dredgers work round the clock to sand-fill the site. On 21 February 2013, a ceremony was held to mark

3286-625: The proposed Atlantic Ocean City, to put in place measure that would reduce the effect of the surge on the environment". The Lagos State chapter of the People's Democratic Party issued an official statement, blaming the ACN (now APC)-led state government's sand filling for the ocean surge. The party called for a stop to the Eko Atlantic project and immediate compensation for the bereaved families. In April 29th 2024, demolition of Landmark beach began; to give way to

3348-608: The reclamation of land of Eko Atlantic, with Goodluck Jonathan , former U.S. president Bill Clinton , Babatunde Fashola, Bola Tinubu , Aminu Tambuwal, and Ibikunle Amosun attending. In March 2014, David Frame, managing director of South Energyx Nigeria Ltd., the firm responsible for the development, confirmed that "The first residential tower will open in 2016". By November 2020, a few buildings, most notably Eko Pearl Towers , had been completed, with several more under construction and at planning stages. The city had become an active venue for popular afro-concerts and sports events like

3410-476: The seabed to bring the sediment in suspension, which then becomes a turbidity current , which flows away down slope, is moved by a second burst of water from the WID or is carried away in natural currents. Water injection results in a lot of sediment in the water which makes measurement with most hydrographic equipment (for instance: singlebeam echosounders) difficult. These dredgers use a chamber with inlets, out of which

3472-461: The seabed with its hull out of the water. Some forms can go on land. Some of these are land-type backhoe excavators whose wheels are on long hinged legs so it can drive into shallow water and keep its cab out of water. Some of these may not have a floatable hull and, if so, cannot work in deep water. Oliver Evans (1755–1819) in 1804 invented the Oruktor Amphibolos, an amphibious dredger which

3534-628: The sediment. These environmental impacts can reduce marine wildlife populations in some cases, contaminate sources of drinking water and interrupt economic activities such as fishing. Dredging is excavation carried out underwater or partially underwater, in shallow waters or ocean waters . It keeps waterways and ports navigable, and assists coastal protection, land reclamation and coastal redevelopment, by gathering up bottom sediments and transporting it elsewhere. Dredging can be done to recover materials of commercial value; these may be high value minerals or sediments such as sand and gravel that are used by

3596-427: The water is pumped with the inlets closed. It is usually suspended from a crane on land or from a small pontoon or barge. Its effectiveness depends on depth pressure. A snagboat is designed to remove big debris such as dead trees and parts of trees from North America waterways. Some of these are any of the above types of dredger, which can operate normally, or by extending legs, also known as spuds, so it stands on

3658-681: The world are currently the Vitruvius, the Mimar Sinan, Postnik Yakovlev (Jan De Nul), the Samson (DEME), the Simson and the Goliath (Van Oord). They featured barge -mounted excavators. Small backhoe dredgers can be track-mounted and work from the bank of ditches. A backhoe dredger is equipped with a half-open shell. The shell is filled moving towards the machine. Usually dredged material is loaded in barges. This machine

3720-446: Was America's first steam-powered road vehicle. These are usually used to recover useful materials from the seabed. Many of them travel on continuous track . A unique variant is intended to walk on legs on the seabed. Fishing dredges are used to collect various species of clams , scallops , oysters or mussels from the seabed. Some dredges are also designed to catch crabs, sea urchins, sea cucumbers, and conch. These dredges have

3782-464: Was a flat-bottomed boat with spikes sticking out of its bottom. As tide current pulled the boat, the spikes scraped seabed material loose, and the tide current washed the material away, hopefully to deeper water. Krabbelaar is the Dutch word for "scratcher". A water injection dredger uses a small jet to inject water under low pressure (to prevent the sediment from exploding into the surrounding waters) into

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3844-572: Was cleared and sold to residential buyers. Subsequent reclamation expanded the area to the extent that Victoria Island Annex is now connected to the Lekki Peninsula. This new, enlarged area is referred to as "Oniru Estate" after the ruling family of the area. Originally designated an upscale residential area, failing infrastructure and overcrowding in the old business district on Lagos Island and lax zoning enforcement in Victoria Island led to

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