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Drainage options for the construction industry include: Point drainage, which intercepts water at gullies (points). Gullies connect to drainage pipes beneath the ground surface, so deep excavation is required to facilitate this system. Support for deep trenches is required in the shape of planking, strutting or shoring.
The subsurface field drainage systems consist of horizontal or slightly sloping channels made in the soil; they can be open ditches, trenches, filled with brushwood and a soil cap, filled with stones and a soil cap, buried pipe drains, tile drains, or mole drains, but they can also consist of a series of wells.
Over-irrigation can cause deep drainage from rising water tables that can lead to problems of irrigation salinity requiring watertable control by some form of subsurface land drainage. However, if the soil is under-irrigated, it gives poor soil salinity control, which leads to increased soil salinity with the consequent buildup of toxic salts ...
Pores (the spaces that exist between soil particles) provide for the passage and/or retention of gasses and moisture within the soil profile.The soil's ability to retain water is strongly related to particle size; water molecules hold more tightly to the fine particles of a clay soil than to coarser particles of a sandy soil, so clays generally retain more water. [2]
Modern drainage systems did not appear until the 19th century in Western Europe, although most of these systems were primarily built to deal with sewage issues rising from rapid urbanization. One such example is that of the London sewerage system, which was constructed to combat massive contamination of the River Thames. At the time, the River ...
Groundwater is stored in two zones, one being the saturated zone, or Aquifer, the other is the pore space of unsaturated soil immediately below the ground surface. Soil moisture is the water held between soil particles in the root zone (rhizosphere) of plants, generally in the top 200 cm of soil. Water storage in the soil profile is extremely ...
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Groundwater recharge is an important process for sustainable groundwater management, since the volume-rate abstracted from an aquifer in the long term should be less than or equal to the volume-rate that is recharged. Recharge can help move excess salts that accumulate in the root zone to deeper soil layers, or into the groundwater system.