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Godew
Godew is a reservoir located in the Inderta ''woreda'' of the Tigray Region in Ethiopia. The earthen dam that holds the reservoir was built in 1990 by the Tigray Bureau of Agriculture and Natural Resources. Environment The catchment of the reservoir is 4 km2 large, with a perimeter of 10.45 km (of which 326 metres is occupied by the dam) and a length of 3260 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 contributes to groundwater recharge 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 .... References {{reflist Reservoirs in Ethiopia 1990 establishments in Ethiopia T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Enderta (woreda)
Enderta (; also transliterated as ʾƎndärta) is one of the woredas in the Tigray Region of Ethiopia. It was named for the former Enderta province, which was later merged into Tigray Province. Located in the Debub Misraqawi (Southeastern) Zone at the eastern edge of the Ethiopian highlands Enderta is bordered on the south by Hintalo Wajirat, on the west by Samre, on the northwest by the Mehakelegnaw (Central) Zone, on the north by the Misraqawi (Eastern) Zone, and on the east by the Afar Region; the city and special zone of Mek'ele is an enclave within Enderta. Towns in Enderta include Aynalem and Qwiha; the historic village of Chalacot is also located in this woreda. At least one monolithic church is located in this woreda: a dedication to Mikael in the village of Zahero, which lies in the eastern part. Demographics Based on the 2007 national census conducted by the Central Statistical Agency of Ethiopia (CSA), this woreda has a total population of 114,297, an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tigray Region
The Tigray Region (or simply Tigray; officially the Tigray National Regional State) is the northernmost Regions of Ethiopia, regional state in Ethiopia. The Tigray Region is the homeland of the Tigrayan, Irob people, Irob and Kunama people. Its capital and largest city is Mekelle. Tigray is the fifth-largest by area, the fourth-most populous, and the fifth-most densely populated of the 11 regional states. Tigray is bordered by Eritrea to the north, the Amhara Region to the south, the Afar Region to the east, and Sudan to the west. Tigray's official language is Tigrinya language, Tigrinya, similar to that of southern Eritrea. The Tigray region had an estimated pre-war population of 7,070,260. 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 Misraqawi Zone, eastern and Maekelay Zone, central Tigray. The much less densely populated lowlands comprise ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ethiopia
Ethiopia, officially the Federal Democratic Republic of Ethiopia, is a landlocked country located in the Horn of Africa region of East Africa. It shares borders with Eritrea to the north, Djibouti to the northeast, Somalia to the east, Kenya to the south, South Sudan to the west, and Sudan to the northwest. Ethiopia covers a land area of . , it has around 128 million inhabitants, making it the List of countries and dependencies by population, thirteenth-most populous country in the world, the List of African countries by population, second-most populous in Africa after Nigeria, and the most populous landlocked country on Earth. The national capital and largest city, Addis Ababa, lies several kilometres west of the East African Rift that splits the country into the African Plate, African and Somali Plate, Somali tectonic plates. Early modern human, Anatomically modern humans emerged from modern-day Ethiopia and set out for the Near East and elsewhere in the Middle Paleolithi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reservoir
A reservoir (; ) is an enlarged lake behind a dam, usually built to water storage, store fresh water, often doubling for hydroelectric power generation. Reservoirs are created by controlling a watercourse that drains an existing body of water, interrupting a watercourse to form an Bay, embayment within it, excavating, or building any number of retaining walls or levees to enclose any area to store water. 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 of the reservoir. These reservoirs can either be ''on-stream reservoirs'', which are located on the original streambed of the downstream river and are filled by stream, creeks, rivers or rainwater that surface runoff, runs off the surrounding forested catchments, or ''off-stream reservoirs'', which receive water diversion, diverted water from a nearby stream or aqueduct (water supply), aq ... [...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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Catchment
A drainage basin is an area of land in which 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 the drainage divide line. A drainage basin's boundaries are determined by watershed delineation, a common task in environmental engineering and science. In a closed drainage basin, or endorheic basin, rather than flowing to the ocean, water converges toward the interior ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Siltation
Siltation is water pollution caused by particulate terrestrial 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 agricultural practices, leading to soil ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Seepage
In soil mechanics, seepage is the movement of water through soil. If fluid pressures in a soil deposit are uniformly increasing with depth according to u = \rho_w g z_w, where z_w is the depth below the water table, then hydrostatic conditions will prevail and the fluids will be flowing through the soil. However, if the water table is sloping or there is a perched water table as indicated in the accompanying sketch, then seepage will occur. For steady state seepage, the seepage velocities are not varying with time. If the water tables are changing levels with time, or if the soil is in the process of consolidation, then steady state conditions do not apply. Darcy's law Darcy's law states that the volume of flow of the pore fluid through a porous medium per unit time is proportional to the rate of change of excess fluid pressure with distance. The constant of proportionality includes the viscosity of the fluid and the intrinsic permeability of the soil. For the simple case of a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Groundwater Recharge
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 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 the subsurface. The most common methods to estimate recharge rates are: chloride mass balance (CMB); soil physics methods; environmental and isotopic tracers; groundwater-level fluctuation methods; water balance (WB) methods (including groundwater models (GMs)); and the estimation of baseflow (BF) to rivers. Text was copied from this source, which is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reservoirs In Ethiopia
A reservoir (; ) is an enlarged lake behind a dam, usually built to store fresh water, often doubling for hydroelectric power generation. Reservoirs are created by controlling a watercourse that drains an existing body of water, interrupting a watercourse to form an embayment within it, excavating, or building any number of retaining walls or levees to enclose any area to store water. 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 of the reservoir. These reservoirs can either be ''on-stream reservoirs'', which are located on the original streambed of the downstream river and are filled by creeks, rivers or rainwater that runs off the surrounding forested catchments, or ''off-stream reservoirs'', which receive diverted water from a nearby stream or aqueduct or pipeline water from other on-stream reservoirs. Dams are typically lo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
