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Gereb Mihiz
Gereb Mihiz is a reservoir located in the Hintalo Wajirat ''woreda'' of the Tigray Region in Ethiopia. The earthen dam that holds the reservoir was built in 1998 by SAERT. Dam characteristics * Dam height: 17.5 metres * Dam crest length: 403 metres * Spillway width: 15 metres Capacity * Original capacity: 1300000 m³ * Dead storage: 325000 m³ * Reservoir area: 30 ha In 2002, the life expectancy of the reservoir (the duration before it is filled with sediment) was estimated at 21 years. Irrigation * Designed irrigated area: 80 ha * Actual irrigated area in 2002: 38 ha Environment The catchment of the reservoir is 17.16 km² large, with a perimeter of 20.38 km and a length of 4910 metres. The reservoir suffers from rapid siltation. The lithology of the catchment is Mekelle Dolerite and Agula Shale. Part of the water that could be used for irrigation is lost through seepage; the positive side-effect is that this c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ethiopia
Ethiopia, , om, Itiyoophiyaa, so, Itoobiya, ti, ኢትዮጵያ, Ítiyop'iya, aa, Itiyoppiya officially the Federal Democratic Republic of Ethiopia, is a landlocked country in the Horn of Africa. It shares borders with Eritrea to the north, Djibouti to the northeast, Somalia to the east and northeast, Kenya to the south, South Sudan to the west, and Sudan to the northwest. Ethiopia has a total area of . As of 2022, it is home to around 113.5 million inhabitants, making it the 13th-most populous country in the world and the 2nd-most populous in Africa after Nigeria. The national capital and largest city, Addis Ababa, lies several kilometres west of the East African Rift that splits the country into the African and Somali tectonic plates. Anatomically modern humans emerged from modern-day Ethiopia and set out to the Near East and elsewhere in the Middle Paleolithic period. Southwestern Ethiopia has been proposed as a possible homeland of the Afroasiatic la ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hintalo
Hintalo ( ti, ሕንጣሎ), also called Antalo, was Administrative Center of Enderta’s historical wereda of Gabat Melash, is a small town located in the Debub Misraqawi (Southeastern) Zone of the Tigray Region of Ethiopia. It lies on a plateau with an elevation variously reported as 2050 to 2102 meters above sea level. It lies some 20 miles south of Mekelle, the capital of Tigray. The urge to control this fortified mountainous place has provoked frequent engagements among various Tigrayan chiefs since the 17th century. Hintalo flourished as a town in the last quarter of the 18th and beginning of the 19th century. History Origins Historically, Hintalo was the capital city of Enderta Province. Located on a high plateau beneath the south face of Amba Aradam, which made the town a natural fortress. With the advent of ''ras'' Wolde Selassie of Enderta to power as Governor of all Tigray, Hintalo became the political center of Tigray. Earlier, it was the residence and a safe h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reservoir
A reservoir (; from French ''réservoir'' ) is an enlarged lake behind a dam. Such a dam may be either artificial, built to store fresh water or it may be a natural formation. Reservoirs can be created in a number of ways, including controlling a watercourse that drains an existing body of water, interrupting a watercourse to form an embayment within it, through excavation, or building any number of retaining walls or levees. In other contexts, "reservoirs" may refer to storage spaces for various fluids; they may hold liquids or gasses, including hydrocarbons. ''Tank reservoirs'' store these in ground-level, elevated, or buried tanks. Tank reservoirs for water are also called cisterns. Most underground reservoirs are used to store liquids, principally either water or petroleum. Types Dammed valleys Dammed reservoirs are artificial lakes created and controlled by a dam constructed across a valley, and rely on the natural topography to provide most of the basin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hintalo Wajirat
Hintalo Wajirat () is one of the Districts of Ethiopia or ''woredas'' in the Tigray Region of Ethiopia. It is named after its largest town, Hintalo, and the Wajirat Mountains in the southern part of the woreda. Located in the Debub Misraqawi (Southeastern) Zone at the eastern edge of the Ethiopian highlands Hintalo Wajirat is bordered on the south by the Debubawi (Southern) Zone, on the west by Samre, on the north by Enderta, and on the east by the Afar Region. Other towns in Hintalo Wajirat include Adi Gudem, and Bahri Tseba. History Hintalo (ሕንጣሎ) has been the capital city of Gabat-Milash woreda (ጋባት ምላሽ) as well as the capital city of Enderta province, with Wajirat (ዋጅራት) itself being a historical district of the province of Enderta, Wajirat's historical capital city was Debub (ደቡብ). The current Hintalo Wajirat woreda is the merger of Gabat Milash and Wajirat, and both Gabatmilash as well as Wajirat have been an integral part of En ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tigray Region
The Tigray Region, officially the Tigray National Regional State, is the northernmost regional state in Ethiopia. The Tigray Region is the homeland of the Tigrayan, Irob, and Kunama people. Its capital and largest city is Mekelle. Tigray is the fifth-largest by area, the fifth-most populous, and the fifth-most densely populated of the 11 regional states. Tigray's official language is Tigrinya, similar to that spoken in Eritrea just to the North. The estimated population as of 2019 is 5,443,000. The majority of the population (c. 80%) are farmers, contributing 46% to the regional gross domestic product (2009). The highlands have the highest population density, especially in eastern and central Tigray. The much less densely populated lowlands comprise 48% of Tigray's area. Like many parts of Africa, Tigray is far from a religious monolith. Despite the historical identification of Ethiopia with Orthodox Christianity, the presence of Islam in Ethiopia is as old as the relig ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Earthen Dam
An embankment dam is a large artificial dam. It is typically created by the placement and compaction of a complex semi-plastic mound of various compositions of soil or rock. It has a semi-pervious waterproof natural covering for its surface and a dense, impervious core. This makes the dam impervious to surface or seepage erosion. Such a dam is composed of fragmented independent material particles. The friction and interaction of particles binds the particles together into a stable mass rather than by the use of a cementing substance. Types Embankment dams come in two types: the earth-filled dam (also called an earthen dam or terrain dam) made of compacted earth, and the rock-filled dam. A cross-section of an embankment dam shows a shape like a bank, or hill. Most have a central section or core composed of an impermeable material to stop water from seeping through the dam. The core can be of clay, concrete, or asphalt concrete. This type of dam is a good choice for sites wi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
SAERT
Sustainable Agriculture and Environmental Rehabilitation in Tigray (SAERT) was a parastatal organisation in the Tigray Region of Ethiopia. It was established in 1995 for "policymaking, design and construction of dams and canals, and the maintenance of dams and water distribution systems". SAERT was funded jointly by the United Nations Development Programme, United Nations Economic Commission for Africa and Food and Agriculture Organization of the United Nations, with the Regional Government of Tigray sharing project financing in kind. Initially, SAERT planned on small-scale irrigation projects in the Mekelle plateau through constructions of 500 earthen micro-dams. Realizing that goal was too large, they concentrated on a few of the nearby drought-prone districts of Atsbi Wenberta, Enderta, Hintalo Wajirat and Saharti Samre. By 2003, SAERT had only constructed 54 dams. Due to several factors, many of the ponds and reservoirs became inoperable; those that remain suffer from heavy s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spillway
A spillway is a structure used to provide the controlled release of water downstream from a dam or levee, typically into the riverbed of the dammed river itself. In the United Kingdom, they may be known as overflow channels. Spillways ensure that water does not damage parts of the structure not designed to convey water. Spillways can include floodgates and fuse plugs to regulate water flow and reservoir level. Such features enable a spillway to regulate downstream flow—by releasing water in a controlled manner before the reservoir is full, operators can prevent an unacceptably large release later. Other uses of the term "spillway" include bypasses of dams and outlets of channels used during high water, and outlet channels carved through natural dams such as moraines. Water normally flows over a spillway only during flood periods, when the reservoir has reached its capacity and water continues entering faster than it can be released. In contrast, an intake tower is a stru ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dead Storage
Death is the irreversible cessation of all biological functions that sustain an organism. For organisms with a brain, death can also be defined as the irreversible cessation of functioning of the whole brain, including brainstem, and brain death is sometimes used as a legal definition of death. The remains of a former organism normally begin to decompose shortly after death. Death is an inevitable process that eventually occurs in almost all organisms. Death is generally applied to whole organisms; the similar process seen in individual components of an organism, such as cells or tissues, is necrosis. Something that is not considered an organism, such as a virus, can be physically destroyed but is not said to die. As of the early 21st century, over 150,000 humans die each day, with ageing being by far the most common cause of death. Many cultures and religions have the idea of an afterlife, and also may hold the idea of judgement of good and bad deeds in one's life (heaven, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Catchment
A drainage basin is an area of land where all flowing surface water converges to a single point, such as a river mouth, or flows into another body of water, such as a lake or ocean. A basin is separated from adjacent basins by a perimeter, the '' drainage divide'', made up of a succession of elevated features, such as ridges and hills. A basin may consist of smaller basins that merge at river confluences, forming a hierarchical pattern. Other terms for a drainage basin are catchment area, catchment basin, drainage area, river basin, water basin, and impluvium. In North America, they are commonly called a watershed, though in other English-speaking places, "watershed" is used only in its original sense, that of a drainage divide. In a closed drainage basin, or endorheic basin, the water converges to a single point inside the basin, known as a sink, which may be a permanent lake, a dry lake, or a point where surface water is lost underground. Drainage basins are similar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Siltation
Siltation, is water pollution caused by particulate Terrestrial ecoregion, terrestrial Clastic rock, clastic material, with a particle size dominated by silt or clay. It refers both to the increased concentration of suspended sediments and to the increased accumulation (temporary or permanent) of fine sediments on bottoms where they are undesirable. Siltation is most often caused by soil erosion or sediment spill. It is sometimes referred to by the ambiguous term "sediment pollution", which can also refer to a chemical contamination of sediments accumulated on the bottom, or to pollutants bound to sediment particles. Although "siltation" is not perfectly stringent, since it also includes particle sizes other than silt, it is preferred for its lack of ambiguity. Causes The origin of the increased sediment transport into an area may be erosion on land or activities in the water. In rural areas, the erosion source is typically soil degradation by intensive or inadequate agricult ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Seepage
Soil mechanics is a branch of soil physics and applied mechanics that describes the behavior of soils. It differs from fluid mechanics and solid mechanics in the sense that soils consist of a heterogeneous mixture of fluids (usually air and water) and particles (usually clay, silt, sand, and gravel) but soil may also contain organic solids and other matter.Mitchell, J.K., and Soga, K. (2005) Fundamentals of soil behavior, Third edition, John Wiley and Sons, Inc., .Powrie, W., Spon Press, 2004, ''Soil Mechanics – 2nd ed'' A Guide to Soil Mechanics, Bolton, Malcolm, Macmillan Press, 1979. Along with rock mechanics, soil mechanics provides the theoretical basis for analysis in geotechnical engineering, a subdiscipline of civil engineering, and engineering geology, a subdiscipline of geology. Soil mechanics is used to analyze the deformations of and flow of fluids within natural and man-made structures that are supported on or made of soil, or structures that are buried in soils.L ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
