Drainage - AbsoluteAstronomy.com

Drainage is the natural or artificial removal of surface and sub-surface water

Groundwater

Groundwater is water located beneath the ground surface in soil pore spaces and in the fractures of rock formations. A unit of rock or an unconsolidated deposit is called an aquifer when it can yield a usable quantity of water. The depth at which soil pore spaces or fractures and voids in rock...

from an area. Many agricultural soils need drainage to improve production or to manage water supplies.

Early history

The ancient Indus systems of sewerage and drainage that were developed and used in cities throughout the civilization were far more advanced than any found in contemporary urban sites in the Middle East

Ancient Near East

The ancient Near East was the home of early civilizations within a region roughly corresponding to the modern Middle East: Mesopotamia , ancient Egypt, ancient Iran The ancient Near East was the home of early civilizations within a region roughly corresponding to the modern Middle East: Mesopotamia...

and even more efficient than those in some areas of modern Pakistan and India today. All houses in the major cities of Harappa

Harappa

Harappa is an archaeological site in Punjab, northeast Pakistan, about west of Sahiwal. The site takes its name from a modern village located near the former course of the Ravi River. The current village of Harappa is from the ancient site. Although modern Harappa has a train station left from...

and Mohenjo-daro

Mohenjo-daro

Mohenjo-daro is an archeological site situated in what is now the province of Sindh, Pakistan. Built around 2600 BC, it was one of the largest settlements of the ancient Indus Valley Civilization, and one of the world's earliest major urban settlements, existing at the same time as the...

had access to water

Water

Water is a chemical substance with the chemical formula H2O. A water molecule contains one oxygen and two hydrogen atoms connected by covalent bonds. Water is a liquid at ambient conditions, but it often co-exists on Earth with its solid state, ice, and gaseous state . Water also exists in a...

and drainage facilities. Waste water was directed to covered drains, which lined the major streets.

Drainage in the 19th century

From the 1881 Household Cyclopedia
Household Cyclopedia
The Household Cyclopedia was an American guide to housekeeping published in 1881.- External links :**...

:

This operation is always best performed in spring

Spring (season)

Spring is one of the four temperate seasons, the transition period between winter and summer. Spring and "springtime" refer to the season, and broadly to ideas of rebirth, renewal and regrowth. The specific definition of the exact timing of "spring" varies according to local climate, cultures and...

or summer

Summer

Summer is the warmest of the four temperate seasons, between spring and autumn. At the summer solstice, the days are longest and the nights are shortest, with day-length decreasing as the season progresses after the solstice...

, when the ground is dry. Main drains ought to be made in every part of the field where a cross-cut

Fill

Fill may refer to:*Fill dirt, soil added to an area.*Fill , a short segment of instrumental music.*In textiles, the filling yarn is the same as weft, the yarn which is shuttled back and forth across the warp to create a woven fabric....

or open drain was formerly wanted; they ought to be cut four feet (1.2 m) deep, upon an average. This completely secures them from the possibility of being damaged by the treading of horse

Horse

The horse is one of two extant subspecies of Equus ferus, or the wild horse. It is a single-hooved mammal belonging to the taxonomic family Equidae. The horse has evolved over the past 45 to 55 million years from a small multi-toed creature into the large, single-toed animal of today...

s or cattle

Cattle

Cattle are the most common type of large domesticated ungulates. They are a prominent modern member of the subfamily Bovinae, are the most widespread species of the genus Bos, and are most commonly classified collectively as Bos primigenius...

, and being so far below the small drains, clears the water finely out of them. In every situation, pipe-turfs for the main drains, if they can be had, are preferable. If good stiff clay

Clay

Clay is a general term including many combinations of one or more clay minerals with traces of metal oxides and organic matter. Geologic clay deposits are mostly composed of phyllosilicate minerals containing variable amounts of water trapped in the mineral structure.- Formation :Clay minerals...

, a single row of pipe-turf; if sandy, a double row. When pipe-turf cannot be got conveniently, a good wedge drain may answer well, when the subsoil is a strong, stiff clay; but if the subsoil be only moderately so, a thorn drain, with couples below, will do still better; and if the subsoil is very sandy, except pipes can be had, it is in vain to attempt under-draining the fiel d by any other method. It may be necessary to mention here that the size of the main drains ought to be regulated according to the length and declivity of the run, and t eihther it can be he quantity of water to be carried off by them. It is always safe, however, to have the main drains large, and plenty of them; for economy here seldom turns out well.

Having finished the main drains, proceed next to make a small drain in every furrow of the field if the ridges formerly have not been less than fifteen feet (4.6 m) wide. But if that should be the case, first level the ridges, and make the drains in the best direction, and at such a distance from each other as may be thought necessary. If the water rises well in the bottom of the drains, they ought to be cut three feet (1 m) deep, and in this ease would dry the field sufficiently well, although they were from twenty-five to thirty feet (8 to 10 m) asunder; but if the water does not draw well to the bottom of the drains, two feet (0.6 m) will be a sufficient deepness for the pipe-drain, and two and a half feet (1 m) for the wedge drain. In no case ought they to be shallower where the field has been previously leveled. In this instance, however, as the surface water is carried off chiefly by the water sinking immediately into the top of the drains, it will be necessary to have the drains much nearer each other—say from fifteen to twenty feet (4.6 to 6 m). If the ridges are more than fifteen feet (4.6 m) wide, however broad and irregular they may be, follow invariably the line of the old furrows, as the best direction for the drains; and, where they are high-gathered ridges, from twenty to twenty-four inches will be a sufficient depth for the pipe-drain, and from twenty-four to thirty inches for the wedge-drain. Particular care should be taken in connecting the small and main drains together, so that the water may have a gentle declivity, with free access into the main drains.

When the drains are finished, the ridges are cleaved down upon the drains by the plough

Plough

The plough or plow is a tool used in farming for initial cultivation of soil in preparation for sowing seed or planting. It has been a basic instrument for most of recorded history, and represents one of the major advances in agriculture...

; and where they had been very high formerly, a second clearing may be given; but it is better not to level the ridges too much, for by allowing them to retain a little of their former shape, the ground being lowest immediately where the drains are, the surface water collects upon the top of the drains; and, by shrinking into them, gets freely away. After the field is thus finished, run the new ridges across the small drains, making them about ten feet (3 m) broad, and continue afterwards to plough the field in the same manner as dry land.

It is evident from the above method of draining that the expense will vary very much, according to the quantity of main drains necessary for the field, the distance of the small drains from each other, and the distance the turf is to be carried.

The advantage resulting from under-draining, is very great, for besides a considerable saving annually of water furrowing, cross cutting, etc., the land can often be ploughed and sow

Sow

Sow may refer to:* Sowing seed* Female animals: badger, bear, pig family* Shape in which metal is cast* Type of siege engine* River Sow, England* "Sow", a poem by Sylvia Plath* Sow , the band/spoken word project comprising Anna Wildsmith-People:...

n to advantage, both in the spring and in the fall of the year, when otherwise it would be found quite impracticable; every species of drilled crops, such as beans, potatoes, turnips, etc., can be cultivated successfully; and every species, both of green and white crops, is less apt to fail in wet and untoward seasons.

Wherever a burst of water appears in any particular spot, the sure and certain way of getting quit of such an evil is to dig hollow drains to such a depth below the surface as is required by the fall or level that can be gained, and by the quantity of water expected to proceed from the burst or spring

Spring (hydrosphere)

A spring—also known as a rising or resurgence—is a component of the hydrosphere. Specifically, it is any natural situation where water flows to the surface of the earth from underground...

. Having ascertained the extent of water to be carried off, taken the necessary levels, and cleared a mouth or loading passage for the water, begin the drain at the extremity next to that leader, and go on with the work till the top of the spring is touched, which probably will accomplish the intended object. But if it should not be completely accomplished, run off from the main drain with such a number of branches as may be required to intercept the water, and in this way disappointment will hardly be experienced. Drains, to be substantially useful, should seldom be less than three feet (1 m) in depth, twenty or twenty four inches thereof to be close packed with stones or wood, according to circumstances. The former are the best materials, but in many places are not to be got in sufficient quantities; recourse therefore, must often be made to the latter, though not so effectual or durable.

It is of vast importance to fill up drains as fast as they are dug out; because, if left open for any length of time, the earth is not only apt to fall in but the sides get into a broken, irregular state, which cannot afterwards be completely rectified. A proper covering of straw or sod

Sod

Sod or turf is grass and the part of the soil beneath it held together by the roots, or a piece of thin material.The term sod may be used to mean turf grown and cut specifically for the establishment of lawns...

should be put upon the top of the materials, to keep the surface earth from mixing with them; and where wood is the material used for filling up, a double degree of attention is necessary, otherwise the proposed improvement may be effectually frustrated.

The pit method of draining is a very effectual one, if executed with judgment. When it is sufficiently ascertained where the bed of water is deposited, which can easily be done by boring with an auger, sink a pit into the place of a size which will allow a man freely to work within its bounds. Dig this pit of such a depth as to reach the bed of the water meant to be carried off; and when this depth is attained, which is easily discerned by the rising of the water, fill up the pit with great land-stones and carry off the water by a stout drain to some adjoining ditch or mouth, whence it may proceed to the nearest river.

Current practices

Geotextiles

Modern drainage systems incorporate geotextile

Geotextile

Geotextiles are permeable fabrics which, when used in association with soil, have the ability to separate, filter, reinforce, protect, or drain...

filters that retain and prevent fine grains of soil

Soil

Soil is a natural body consisting of layers of mineral constituents of variable thicknesses, which differ from the parent materials in their morphological, physical, chemical, and mineralogical characteristics...

from passing into and clogging the drain. Geotextiles are synthetic textile fabrics specially manufactured for civil

Civil engineering

Civil engineering is a professional engineering discipline that deals with the design, construction, and maintenance of the physical and naturally built environment, including works like roads, bridges, canals, dams, and buildings...

and environmental engineering

Environmental engineering

Environmental engineering is the application of science and engineering principles to improve the natural environment , to provide healthy water, air, and land for human habitation and for other organisms, and to remediate polluted sites...

applications. Geotextiles are designed to retain fine soil particles while allowing water to pass through. In a typical drainage system they would be laid along a trench which would then be filled with coarse granular material

Granular material

A granular material is a conglomeration of discrete solid, macroscopic particles characterized by a loss of energy whenever the particles interact . The constituents that compose granular material must be large enough such that they are not subject to thermal motion fluctuations...

: gravel

Gravel

Gravel is composed of unconsolidated rock fragments that have a general particle size range and include size classes from granule- to boulder-sized fragments. Gravel can be sub-categorized into granule and cobble...

, sea shells, stone

Rock (geology)

In geology, rock or stone is a naturally occurring solid aggregate of minerals and/or mineraloids.The Earth's outer solid layer, the lithosphere, is made of rock. In general rocks are of three types, namely, igneous, sedimentary, and metamorphic...

or rock

Rock (geology)

. The geotextile is then folded over the top of the stone and the trench is then covered by soil. Groundwater

Groundwater

seeps through the geotextile and flows within the stone to an outfall. In high groundwater

Groundwater

conditions a perforated plastic (PVC

Polyvinyl chloride

Polyvinyl chloride, commonly abbreviated PVC, is a thermoplastic polymer. It is a vinyl polymer constructed of repeating vinyl groups having one hydrogen replaced by chloride. Polyvinyl chloride is the third most widely produced plastic, after polyethylene and polypropylene. PVC is widely used in...

or PE

Polyethylene

Polyethylene or polythene is the most widely used plastic, with an annual production of approximately 80 million metric tons...

) pipe is laid along the base of the drain to increase the volume of water transported in the drain.

Alternatively, prefabricated plastic drainage systems made of HDPE called SmartDitch, often incorporating geotextile, coco

Coco

Coco, CoCo, Co-Co or similar can mean:*Co-Co locomotives, a code for a locomotive wheel arrangement with two six-wheeled bogies with all axles powered, with a separate motor per axle*Co-Co , a British pop group...

fiber or rag filter

Filter (water)

A water filter removes impurities from water by means of a fine physical barrier, a chemical process or a biological process. Filters cleanse water to various extents for irrigation, drinking water, aquariums, and swimming pools.-Methods of filtration:...

s can be considered. The use of these materials has become increasingly more common due to their ease of use which eliminates the need for transporting and laying stone drainage aggregate which is invariably more expensive than a synthetic drain and concrete liners.

Over the past 30 years geotextile and PVC filters have become the most commonly used soil filter media. They are cheap to produce and easy to lay, with factory controlled properties that ensure long term filtration performance even in fine silty soil conditions.

21st century alternatives

Seattle's Public Utilities created a pilot program called Street Edge Alternatives (SEA Streets) Project. The project focuses on designing a system "to provide drainage that more closely mimics the natural landscape prior to development than traditional piped systems".
The streets are characterized by ditches along the side of the roadway, with plantings designed throughout the area.
An emphasis on non curbed sidewalks allows water to flow more freely into the areas of permeable surface on the side of the streets. Because of the plantings the run off water from the urban area does not all directly go into the ground but can also be absorbed into the surrounding environment.
According to the monitoring by Seattle Public Utilities, they report a 99 percent reduction of storm water leaving the drainage project

Drainage in construction

The civil engineer

Civil engineer

A civil engineer is a person who practices civil engineering; the application of planning, designing, constructing, maintaining, and operating infrastructures while protecting the public and environmental health, as well as improving existing infrastructures that have been neglected.Originally, a...

or site engineer is responsible for drainage in construction projects. They set out from the plans all the road

Road

A road is a thoroughfare, route, or way on land between two places, which typically has been paved or otherwise improved to allow travel by some conveyance, including a horse, cart, or motor vehicle. Roads consist of one, or sometimes two, roadways each with one or more lanes and also any...

s, street gutter

Street gutter

A street gutter is a depression running parallel to a road designed to collect rainwater flowing along the street and divert it into a storm drain. Where a curbstone is present, a gutter may simply be formed by the convergence of the road surface and the vertical face of the sidewalk; otherwise, a...

s, drainage, culvert

Culvert

A culvert is a device used to channel water. It may be used to allow water to pass underneath a road, railway, or embankment. Culverts can be made of many different materials; steel, polyvinyl chloride and concrete are the most common...

s and sewers involved in construction

Construction

In the fields of architecture and civil engineering, construction is a process that consists of the building or assembling of infrastructure. Far from being a single activity, large scale construction is a feat of human multitasking...

operations. During the construction of the work on site he/she will set out all the necessary levels for each of the previously mentioned factors.
Site engineers work alongside architect

Architect

An architect is a person trained in the planning, design and oversight of the construction of buildings. To practice architecture means to offer or render services in connection with the design and construction of a building, or group of buildings and the space within the site surrounding the...

s and construction managers, supervisors, planners, quantity surveyor

Quantity surveyor

A quantity surveyor is a professional working within the construction industry concerned with building costs.The profession is one that provides a qualification gained following formal education, specific training and experience that provides a general set of skills that are then applied to a...

s, the general workforce, as well as subcontractors. Typically, most jurisdictions have some body of drainage law

Drainage law

Drainage law is a specific area of water law related to drainage of surface water on real property. It is of great importance in areas where freshwater is scarce, where flooding is common, or where water is in high demand for agricultural or commercial purposes.-Drainage law in the United...

to govern to what degree a landowner can alter the drainage from his parcel.

Green Drain

Enzymatic drain cleaners can be a safer alternative to chemical drain cleaners, and are easier on the environment. They use bacteria or enzymes, which naturally feed on organic waste, such as hair and food waste that often block drains. These tiny organisms, then digest the waste and to recreate beneficial bacteria and enzymes throughout the septic system. In fact, drain cleaners enzyme originally used to clean septic tank

Septic tank

A septic tank is a key component of the septic system, a small-scale sewage treatment system common in areas with no connection to main sewage pipes provided by local governments or private corporations...

s and sewage. Enzymatic drain cleaners are better for the environment because they prevent hazardous chemicals that may leak into soil and water from spreading.

Reasons for artificial drainage

Wetland soils may need drainage to be used for agriculture

Agriculture

Agriculture is the cultivation of animals, plants, fungi and other life forms for food, fiber, and other products used to sustain life. Agriculture was the key implement in the rise of sedentary human civilization, whereby farming of domesticated species created food surpluses that nurtured the...

. In the northern USA

United States

The United States of America is a federal constitutional republic comprising fifty states and a federal district...

and Europe

Europe

Europe is, by convention, one of the world's seven continents. Comprising the westernmost peninsula of Eurasia, Europe is generally 'divided' from Asia to its east by the watershed divides of the Ural and Caucasus Mountains, the Ural River, the Caspian and Black Seas, and the waterways connecting...

, glaciation created numerous small lake

Lake

A lake is a body of relatively still fresh or salt water of considerable size, localized in a basin, that is surrounded by land. Lakes are inland and not part of the ocean and therefore are distinct from lagoons, and are larger and deeper than ponds. Lakes can be contrasted with rivers or streams,...

s which gradually filled with humus to make marsh

Marsh

In geography, a marsh, or morass, is a type of wetland that is subject to frequent or continuous flood. Typically the water is shallow and features grasses, rushes, reeds, typhas, sedges, other herbaceous plants, and moss....

es. Some of these were drained using open ditch

Ditch

A ditch is usually defined as a small to moderate depression created to channel water.In Anglo-Saxon, the word dïc already existed and was pronounced 'deek' in northern England and 'deetch' in the south. The origins of the word lie in digging a trench and forming the upcast soil into a bank...

es and trenches to make muckland

Muck (soil)

Muck is a soil made up primarily of humus from drained swampland. It is known as black soil in The Fens of eastern England, where it was originally mainly fen and bog. It is used there, as in the United States, for growing specialty crops such as onions, carrots, celery, and potatoes...

s, which are primarily used for high value crops such as vegetable

Vegetable

The noun vegetable usually means an edible plant or part of a plant other than a sweet fruit or seed. This typically means the leaf, stem, or root of a plant....

s.

The largest project of this type in the world has been in process for centuries in the Netherlands

Netherlands

The Netherlands is a constituent country of the Kingdom of the Netherlands, located mainly in North-West Europe and with several islands in the Caribbean. Mainland Netherlands borders the North Sea to the north and west, Belgium to the south, and Germany to the east, and shares maritime borders...

. The area between Amsterdam

Amsterdam

Amsterdam is the largest city and the capital of the Netherlands. The current position of Amsterdam as capital city of the Kingdom of the Netherlands is governed by the constitution of August 24, 1815 and its successors. Amsterdam has a population of 783,364 within city limits, an urban population...

, Haarlem

Haarlem

Haarlem is a municipality and a city in the Netherlands. It is the capital of the province of North Holland, the northern half of Holland, which at one time was the most powerful of the seven provinces of the Dutch Republic...

and Leiden was, in prehistoric times swampland and small lakes. Turf cutting (Peat

Peat

Peat is an accumulation of partially decayed vegetation matter or histosol. Peat forms in wetland bogs, moors, muskegs, pocosins, mires, and peat swamp forests. Peat is harvested as an important source of fuel in certain parts of the world...

mining

Mining

Mining is the extraction of valuable minerals or other geological materials from the earth, from an ore body, vein or seam. The term also includes the removal of soil. Materials recovered by mining include base metals, precious metals, iron, uranium, coal, diamonds, limestone, oil shale, rock...

), subsidence

Subsidence

Subsidence is the motion of a surface as it shifts downward relative to a datum such as sea-level. The opposite of subsidence is uplift, which results in an increase in elevation...

and shoreline erosion

Erosion

Erosion is when materials are removed from the surface and changed into something else. It only works by hydraulic actions and transport of solids in the natural environment, and leads to the deposition of these materials elsewhere...

gradually caused the formation of one large lake, the Haarlemmermeer

Haarlemmermeer

Haarlemmermeer is a municipality in the Netherlands, in the province of North Holland. It is a polder, consisting of land reclaimed from water, and the name Haarlemmermeer means Haarlem's Lake, still referring to the body of water from which the region was reclaimed in the 19th century.Its main...

, or lake of Haarlem. The invention of wind

Wind

Wind is the flow of gases on a large scale. On Earth, wind consists of the bulk movement of air. In outer space, solar wind is the movement of gases or charged particles from the sun through space, while planetary wind is the outgassing of light chemical elements from a planet's atmosphere into space...

powered pump

Pump

A pump is a device used to move fluids, such as liquids, gases or slurries.A pump displaces a volume by physical or mechanical action. Pumps fall into three major groups: direct lift, displacement, and gravity pumps...

ing engines in the 15th century permitted drainage of some of the marginal land, but the final drainage of the lake had to await the design of large, steam powered pumps and agreements between regional authorities. The elimination of the lake occurred between 1849 and 1852, creating thousands of km² of new land.

Coastal plains and river deltas may have seasonally or permanently high water table

Water table

The water table is the level at which the submarine pressure is far from atmospheric pressure. It may be conveniently visualized as the 'surface' of the subsurface materials that are saturated with groundwater in a given vicinity. However, saturated conditions may extend above the water table as...

s and must have drainage improvements if they are to be used for agriculture. An example is the flatwoods citrus

Citrus

Citrus is a common term and genus of flowering plants in the rue family, Rutaceae. Citrus is believed to have originated in the part of Southeast Asia bordered by Northeastern India, Myanmar and the Yunnan province of China...

-growing region of Florida

Florida

Florida is a state in the southeastern United States, located on the nation's Atlantic and Gulf coasts. It is bordered to the west by the Gulf of Mexico, to the north by Alabama and Georgia and to the east by the Atlantic Ocean. With a population of 18,801,310 as measured by the 2010 census, it...

. After periods of high rainfall, drainage pumps are employed to prevent damage to the citrus groves from overly wet soils. Rice

Rice

Rice is the seed of the monocot plants Oryza sativa or Oryza glaberrima . As a cereal grain, it is the most important staple food for a large part of the world's human population, especially in East Asia, Southeast Asia, South Asia, the Middle East, and the West Indies...

production requires complete control of water, as fields need to be flooded or drained at different stages of the crop cycle. The Netherlands has also led the way in this type of drainage, not only to drain lowland along the shore, but actually pushing back the sea until the original nation has been greatly enlarged.

In moist climates, soils may be adequate for cropping with the exception that they become waterlogged

Waterlogging

Waterlogging or water logging may refer to:* Waterlogging , saturation of the soil by groundwater sufficient to prevent or hinder agriculture...

for brief periods each year, from snow

Snow

Snow is a form of precipitation within the Earth's atmosphere in the form of crystalline water ice, consisting of a multitude of snowflakes that fall from clouds. Since snow is composed of small ice particles, it is a granular material. It has an open and therefore soft structure, unless packed by...

melt or from heavy rain

Rain

Rain is liquid precipitation, as opposed to non-liquid kinds of precipitation such as snow, hail and sleet. Rain requires the presence of a thick layer of the atmosphere to have temperatures above the melting point of water near and above the Earth's surface...

s. Soils that are predominantly clay

Clay

will pass water very slowly downward, meanwhile plant roots suffocate because the excessive water around the roots eliminates air movement through the soil.

Other soils may have an impervious layer of mineralized soil, called a hardpan

Hardpan

In soil science, agriculture and gardening, hardpan or ouklip is a general term for a dense layer of soil, usually found below the uppermost topsoil layer. There are different types of hardpan, all sharing the general characteristic of being a distinct soil layer that is largely impervious to water...

or relatively impervious rock layers may underlie shallow soils. Drainage is especially important in tree fruit

Fruit tree

A fruit tree is a tree which bears fruit that is consumed or used by people — all trees that are flowering plants produce fruit, which are the ripened ovaries of flowers containing one or more seeds. In horticultural usage, the term 'fruit tree' is limited to those that provide fruit for...

production. Soils that are otherwise excellent may be waterlogged for a week of the year, which is sufficient to kill fruit trees and cost the productivity of the land until replacements can be established. In each of these cases appropriate drainage carries off temporary flushes of water to prevent damage to annual

Annual plant

An annual plant is a plant that usually germinates, flowers, and dies in a year or season. True annuals will only live longer than a year if they are prevented from setting seed...

or perennial

Perennial plant

A perennial plant or simply perennial is a plant that lives for more than two years. The term is often used to differentiate a plant from shorter lived annuals and biennials. The term is sometimes misused by commercial gardeners or horticulturalists to describe only herbaceous perennials...

crops.

Drier areas are often farmed by irrigation

Irrigation

Irrigation may be defined as the science of artificial application of water to the land or soil. It is used to assist in the growing of agricultural crops, maintenance of landscapes, and revegetation of disturbed soils in dry areas and during periods of inadequate rainfall...

, and one would not consider drainage necessary. However, irrigation water always contains minerals and salt

Salt

In chemistry, salts are ionic compounds that result from the neutralization reaction of an acid and a base. They are composed of cations and anions so that the product is electrically neutral...

s, which can be concentrated to toxic levels by evapotranspiration

Evapotranspiration

Evapotranspiration is a term used to describe the sum of evaporation and plant transpiration from the Earth's land surface to atmosphere. Evaporation accounts for the movement of water to the air from sources such as the soil, canopy interception, and waterbodies...

. Irrigated land may need periodic flushes with excessive irrigation water and drainage to control soil salinity.

External links

American Wick Drain- Manufacturer of prefabricated sheet drain
International Geosynthetics Society, information on geotextiles and geosynthetics in general.
WebCom Systems, software created for designing soakaways and filter trenches.
DRAINMOD, software created for modeling agricultural tile and ditch drainage.
Drainage Systems, drainage systems revealed, drainage tips and guide, plans and photos.
River water higher than land
NDS, drainage calculator.
Ancient drains, a series of images of the earliest drainage systems in the ancient Indus city of Mohenjo daro
Draining for Profit, and Draining for Health by George E. Waring, 1867, from Project Gutenberg
Project Gutenberg
Project Gutenberg is a volunteer effort to digitize and archive cultural works, to "encourage the creation and distribution of eBooks". Founded in 1971 by Michael S. Hart, it is the oldest digital library. Most of the items in its collection are the full texts of public domain books...
Drainage Channel, Information on drainage systems for commercial use
Drainage Resources, Systems and Technology, Specification Drainage Resources
Drainage photos
Stormwater Drainage Design information on stormwater design, drainage and on-site detention
Waterlogging, free downloads of articles and software on agricultural land drainage.
ADS-Pipe Drainage Calculators, web based and MS Excel drain calculators.
Principles of Exterior Drainage, installation guide.
SmartDitch, Drainage Control System
Sustainable Residential Design: Improving Water Efficiency Resource Guide

The source of this article is wikipedia, the free encyclopedia. The text of this article is licensed under the GFDL.

Early history

Drainage in the 19th century

Current practices

Geotextiles

21st century alternatives

Drainage in construction

Reasons for artificial drainage

See also

External links