Throughflow

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In hydrology, throughflow, a subtype of interflow (percolation), is the lateral unsaturated flow of water in the soil zone, typically through a highly permeable geologic unit overlying a less permeable one. Water thus returns to the surface, as return flow, before or on entering a stream or groundwater. [1] [2] Once water infiltrates into the soil, it is still affected by gravity and infiltrates to the water table or if permeabliity varies laterally travels downslope. [1] Throughflow usually occurs during peak hydrologic events (such as high precipitation). Flow rates are dependent on the hydraulic conductivity of the geologic medium. [1]

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Geotechnical engineering, also known as geotechnics, is the application of scientific methods and engineering principles to the acquisition, interpretation, and use of knowledge of materials of the Earth's crust and earth materials for the solution of engineering problems and the design of engineering works. It is the applied science of predicting the behavior of the Earth, its various materials and processes towards making the Earth more suitable for human activities and development.

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Aquifer Underground layer of water-bearing permeable rock

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Soil mechanics Branch of soil physics and applied mechanics that describes the behavior of soils

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A darcy and millidarcy are units of permeability, named after Henry Darcy. They are not SI units, but they are widely used in petroleum engineering and geology. Like some other measures of permeability, a darcy has dimensional units in length².

Hydraulic conductivity, symbolically represented as , is a property of vascular plants, soils and rocks, that describes the ease with which a fluid can move through pore spaces or fractures. It depends on the intrinsic permeability of the material, the degree of saturation, and on the density and viscosity of the fluid. Saturated hydraulic conductivity, Ksat, describes water movement through saturated media. By definition, hydraulic conductivity is the ratio of velocity to hydraulic gradient indicating permeability of porous media.

This is an index of articles relating to soil.

The Floridan aquifer system, composed of the Upper and Lower Floridan aquifers, is a sequence of Paleogene carbonate rock which spans an area of about 100,000 square miles (260,000 km2) in the southeastern United States. It underlies the entire state of Florida and parts of Alabama, Georgia, Mississippi, and South Carolina.

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Rain gardens, also called bioretention facilities, are one of a variety of practices designed to treat polluted stormwater runoff. Rain gardens are designed landscape sites that reduce the flow rate, total quantity, and pollutant load of runoff from impervious urban areas like roofs, driveways, walkways,and parking lots, and compacted lawn areas. Rain gardens rely on plants and natural or engineered soil medium to retain stormwater and increase the lag time of infiltration, while remediating and filtering pollutants carried by urban runoff. Rain gardens provide a method to reuse and optimize any rain that falls, reducing or avoiding the need for additional irrigation. A benefit of planting rain gardens is the consequential decrease in ambient air and water temperature, a mitigation that is especially effective in urban areas containing an abundance of impervious surfaces that absorb heat in a phenomenon known as the heat-island effect.

Surface runoff Flow of excess rainwater not infiltrating in the ground over its surface

Surface runoff is the flow of water occurring on the ground surface when excess rainwater, stormwater, meltwater, or other sources, can no longer sufficiently rapidly infiltrate in the soil. This can occur when the soil is saturated by water to its full capacity, and that the rain arrives more quickly than the soil can absorb it. Surface runoff often occurs because impervious areas do not allow water to soak into the ground. Surface runoff is a major component of the water cycle. It is the primary agent of soil erosion by water. The land area producing runoff that drains to a common point is called a drainage basin.

In hydrology, interflow is the lateral movement of water in the unsaturated zone, or vadose zone, that first returns to the surface or enters a stream prior to becoming groundwater. Interflow is sometimes used interchangeably with throughflow; however, throughflow is specifically the subcomponent of interflow that returns to the surface, as overland flow, prior to entering a stream or becoming groundwater. Interflow occurs when water infiltrates into the subsurface, hydraulic conductivity decreases with depth, and lateral flow proceeds downslope. As water accumulates in the subsurface, saturation may occur, and interflow may exfiltrate as return flows, becoming overland flow.

Subsurface flow, in hydrology, is the flow of water beneath earth's surface as part of the water cycle.

Infiltration basin

An infiltration basin, is a type of device that is used to manage stormwater runoff, prevent flooding and downstream erosion, and improve water quality in an adjacent river, stream, lake or bay. It is essentially a shallow artificial pond that is designed to infiltrate stormwater through permeable soils into the groundwater aquifer. Infiltration basins do not release water except by infiltration, evaporation or emergency overflow during flood conditions.

Bioclogging or biological clogging is clogging of pore space in soil by microbial biomass; their body and their byproducts such as extracellular polymeric substance (EPS). The microbial biomass blocks the pathway of water in the pore space, forming a certain thickness of impermeable layer in soil, and it reduces the rate of infiltration of water remarkably.

References

  1. 1 2 3 Fetter, C. (2001). Applied Hydrogeology. New Jersey: Prentice-Hall. p. 41. ISBN   0130882399.
  2. Selby, M. (2005). Hillslope Materials and Processes. New York: Oxford University Press. p. 216. ISBN   0198741839.