Saeed Ur Rehman

Groundwater Groundwater is water that is trapped in rock and soil pits and cracks in rock structures beneath the earth's surface. When a rock unit or consolidated deposit is able to produce useful water it is called a reservoir. The water table is the depth at which the soil holes or cracks and voids in the rock are completely saturated with water. Groundwater is recharged from the surface; It can be released naturally from the surface at springs and seas and form ice or swamps. Groundwater is often withdrawn for agricultural, municipal and industrial use by building and maintaining extraction wells. Hydrogeology is the study of the distribution and movement of groundwater, also known as groundwater hydrology. In general, groundwater is considered to be water that flows through shallow reservoirs, but, in a technical sense, includes soil moisture, permanent frost (frozen soil), very low permeability, and deep groundwater. Thermal or oil structure can also be water. Groundwater is intended to provide lubrication that affects the movement of bugs. Most of the earth's subsoil is likely to contain some water, which in some cases may be mixed with other liquids. Groundwater is often cheaper, more convenient than surface water and less vulnerable to pollution. Therefore, it is commonly used for public water supply. For example, groundwater is the largest source of usable water storage in the United States, and California has the highest annual groundwater extraction of all states. Groundwater holds more water than all surface reservoirs and lakes in the United States, including the Great Lakes. Most municipal water supplies are taken entirely from groundwater. There are environmental issues related to groundwater use. For example, contaminated groundwater is less visible than water in rivers and lakes and is much harder to clean. Groundwater pollution is often caused by improper disposal of waste on land. Major sources include industrial and household chemicals and waste, excess fertilizers and pesticides used in agriculture, industrial waste ponds, mine residues and process sewage, industrial frocking, oil field salt pits, underground oil storage tanks and pipelines. Contains seaweed, sewage sludge and septic. In addition, groundwater infiltrates coastal areas with saltwater and causes landslides when it is constantly flowing, leading to sinking cities (such as Bangkok) and elevation damage (such as the Central Valley of California). Lost several meters). These problems are exacerbated by rising sea levels and other changes due to climate change, which is changing global precipitation and water scarcity. Aquifer is a porous substrate layer that holds and circulates groundwater. When water flows directly between the surface of the reservoir and the saturated area, the reservoir is not constrained. Gravity causes water to flow downwards because the deeper parts of integrated reservoirs are generally more saturated. The upper level of this saturated layer of the integrated reservoir is called the water table or phytic surface. Below the water table, usually all the holes are filled with water, which is the phytic zone. A low-porosity surface that allows limited circulation of groundwater is called aquitard. Aquifer is groundwater with very low porosity that is almost impermeable to groundwater. A limited reservoir is a reservoir that is covered with a relatively inaccessible rock layer or surface such as a reservoir or reservoir. If a limited reservoir moves downward from its recharge area, the pressure will increase as groundwater flows. It forms artesian wells, which flow freely without the need for a pump and rise to a height above the stagnant water table above, the unified, reservoir. Groundwater accounts for thirty percent of the world's freshwater supply, accounting for 0.76% of the world's total water, including oceans and perennial ice. 99% of the world's liquid freshwater is groundwater. Global groundwater storage is equal to the amount of freshwater stored in ice and ice packs, including those at the North and South Poles. It is an important resource that acts as a buffer natural reservoir against surface water depletion, as it does during droughts. When this recharge reaches the water level, groundwater is naturally replaced by surface water from rain, streams and rivers. Groundwater can be a long-term 'reservoir' of natural water cycle (habitat times range from days to millennia); as opposed to short-term water reservoirs such as climate and fresh surface water (residence time can range from minutes). This figure shows how long groundwater (beyond surface recharge) takes longer to complete its natural cycle. The Great Artesian Basin in central and eastern Australia is one of the largest limited reservoir systems in the world, extending approximately 2 million km. By analyzing the trace elements in the water extracted from the deep groundwater, hydro geologists were able to determine that the water extracted from these reservoirs was more than 1 million years old. By comparing the ages of groundwater obtained from different parts of the Great Artesian Basin, hydro geologists have found that aging is increasing throughout the basin. If water is recharged in reservoirs along with the Eastern Divide, there will be a shorter lifespan. As groundwater flows westward across the continent, it increases with age, making it the oldest groundwater in the western parts. This means that the groundwater flowing through the Great Artesian Basin will travel approximately 1000 km from the recharge source in 1 million years, averaging 1 m per year.