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overfilled if it is on a side of the drain which receives a much larger volume of water, such as one pipe being closer to an uphill slope, or closer to a roofline that drips near the French drain. When a pipe becomes overfilled, water can seep sideways into a parallel pipe, as a form of load-balancing, so that neither pipe becomes slowed by air bubbles, as might happen in a full-pipe with no upper air space.
390:
In most homes, an external French drain or drain tile is installed around the foundation walls before the foundation soil is backfilled. It is laid on the bottom of the excavated area, and a layer of stone is laid on top. In many cases, a filter fabric is then laid on top of the stone to keep fine
296:
Depending on the expected level and volume of rainwater or runoff, French drains can be widened or also fitted on two or three underground drainpipes. Multiple pipes also provide for redundancy, in case one pipe becomes overfilled or clogged by a rupture or defect in the piping. A pipe might become
231:
This form comprises a perforated pipe surrounded by gravel. It is similar to the traditional French drain, the gravel or aggregate material of which extends to the surface of the ground and is uncovered to permit collection of water, except that a curtain drain does not extend to the surface and
215:
and roots from entering and clogging the pipe. The perforated pipe provides a minor subterranean volume of storage for water, yet the prime purpose is drainage of the area along the full length of the pipe via its perforations and to discharge any surplus water at its terminus. The direction of
152: in (0.32 cm) gap in between the sections to admit water. Later, specialized drain tiles were designed with perforations. To prevent clogging, the size of the gravel varied from coarse in the center to fine on the outside and was selected contingent on the gradation of the surrounding
272:
This form comprises a subterranean perforated pipe from which extends perpendicularly upward along its length a thin vertical section, denominated the "fin", of aggregate material for drainage to the pipe. The length is 200 mm (7.9 in). This form is less expensive to build than a
207:. An inclination of 1 in 100 to 1 in 200 is typical. Lining the bottom of the ditch with clay or plastic pipe increases the volume of water that can flow through the drain. Modern French drain systems are made of perforated pipe, for example weeping tile surrounded by sand or gravel, and
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from the surrounding soils. Envelopes are the gravel, stone, rock, or surrounding pipe. These are permeable materials placed around pipe or drainage products to improve flow conditions in the area immediately around the drain and for improving bedding and structural backfill conditions.
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or run off water, and may connect into the underground pipes so as to rapidly divert surface water; it preferably has a cleanable filter to avoid migration of surface debris to the subterranean area that would clog the
156:. The sizes of particles were critical to prevent the surrounding soil from washing into the pores, i. e., voids between the particles of gravel and thereby clogging the drain. The later development of
122:
The earliest forms of French drains were simple ditches that were pitched from a high area to a lower one and filled with gravel. These may have been invented in
508:
163:
Subsurface drainage systems have been used for centuries. They have many forms that are similar in design and function to the traditional French drain.
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and as an alternative to open ditches or storm sewers for streets and highways. Alternatively, French drains may be used to distribute water, such as a
135:
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from the septic tank is fed into weeping tiles buried shallowly in the drain field. The weeping tile spreads the liquid throughout the drain field.
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Farm
Drainage: The Principles, Processes, and Effects of Draining Land with Stones, Wood, Plows, and Open Ditches, and Especially with Tiles
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646:. Available from nepis.epa.gov (search "Storm Water Management Fact Sheet Non-Storm Water Discharges to Storm Sewers") retrieved Feb 2022
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sediments and particles from entering. Once the drain is installed, the area is backfilled, and the system is left alone until it clogs.
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where plants absorb and hold the drained water. This is useful if city water systems or other wastewater areas are unavailable.
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Design Manual for Roads and
Bridges, Volume 4: Drainage (Part 5: Determination of Pipe Bedding Combinations for Drainage Works)
91:). When the pipe is draining, it "weeps", or exudes liquids. It was named during a time period when drainpipes were made from
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of waterlogged fields. Such fields are called "tiled". Weeping tiles can be used anywhere that soil needs to be drained.
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instead is covered by soil, in which turf grass or other vegetation may be planted, so that the drain is concealed.
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In the UK, local authorities may have specific requirements for the outfall of a French drain into a ditch or
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French drains are often installed around a home foundation in two different ways, or in combination of both:
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Area of gravel at foot of retaining wall to encourage water away from the wall (French drain): note the
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or landscaping textile. Landscaping textiles prevent migration of the drainage material and prevent
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304:, may include sand and gravel, placed around the drainage pipe or envelope to restrict migration of
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French drains are primarily used to prevent ground and surface water from penetrating or damaging
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142:(1859). French's own drains were made of sections of ordinary roofing tile that were laid with a
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131:
642:"Storm Water Management Fact Sheet Non-Storm Water Discharges to Storm Sewers" publ 1999 by
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541:. New Delhi, India: International Commission on Irrigation and Drainage, 1990. Page 186.
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669:(Publication HA 40/01 ed.). Stationery Office. p. B1–2. Archived from
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552:"What's So French About French Drains and Other Musings on Concord Agriculture"
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In the US, municipalities may require permits for building drainage systems as
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Installed underneath the basement floor on the inside perimeter of the basement
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A wye-joining a perforated and solid corrugated pipe to a buried solid outlet
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percolation depends on the relative conditions within and without the pipe.
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Guidelines on the
Construction of Horizontal Subsurface Drainage Systems
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351:. Statements consisting only of original research should be removed.
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Cross-section view showing French drain with two underground pipes.
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619:"French Drain Services – Drainage Systems Installation and Repair"
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477: – Designed to reduce the potential impact of development
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sewage treatment system. French drains are also used behind
71:, or both, with or without a perforated pipe that redirects
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What are French drains? Why are they called French drains?
528:. South Holland, Ill.: Goodheart-Willcox, 1991. 116. Print.
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This form distributes waste water that a septic tank emits.
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153:
594:"Pros and Cons to Installing a French Drain for Your Home"
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A French drain can end, i.e., open at a downhill slope,
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Buried around the external side of the foundation wall
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French drains can be used in farmers' fields for the
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Filters are made from permeable materials, typically
459: – Form of engineered sump or percolation pond
79:away from an area. The perforated pipe is called a
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434:to be free of specific contaminants and sediment.
406:Weeping tiles are used for the opposite reason in
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453: – Pit to allow surface waste water to drain
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582:. New York, New York: Orange Judd and Company.
644:United States Environmental Protection Agency
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483: – Form of agricultural drainage system
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367:Learn how and when to remove this message
471: – Foundation construction approach
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175:Highway French drain under construction
35:discharges away from the retaining wall
23:A diagram of a traditional French drain
734:Foundations (buildings and structures)
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524:Gradwell, John B., and Malcolm Welch.
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224:Variations of French drains include:
43:(also known by other names including
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160:greatly simplified this technique.
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687:Non-residential French drains are
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138:described and popularized them in
114:to relieve ground water pressure.
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203:Ditches are dug manually or by a
183:Coarse washed stone base in place
136:Assistant U.S. Treasury Secretary
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248:This form combines drainage of
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1:
526:Technology--shaping our world
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695:How to Install French Drains
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7:
660:UK Highways Agency (2001).
475:Sustainable drainage system
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347:the claims made and adding
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106:at the outlet of a typical
16:Sub-surface drainage system
10:
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598:www.thearchitectsguide.com
465: – Drainage structure
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729:Environmental engineering
576:French, Henry F. (1859).
273:traditional French drain.
469:Rubble trench foundation
430:requires water sent to
306:non-colloidal particles
191:Filter fabric over pipe
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132:Concord, Massachusetts
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749:Stormwater management
689:regulated in the U.S.
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739:Hydraulic structures
252:and interception of
100:building foundations
408:septic drain fields
701:2016-10-15 at the
463:Percolation trench
457:Infiltration basin
332:possibly contains
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128:Henry Flagg French
104:septic drain field
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511:. 8 October 2009.
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334:original research
260:Interceptor drain
238:This form drains
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509:"Drain Francais"
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245:Collector drain
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130:(1813–1885) of
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112:retaining walls
83:(also called a
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678:. Retrieved
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627:. Retrieved
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602:. Retrieved
600:. 2020-10-15
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560:. Retrieved
556:the original
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432:storm drains
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414:. Clarified
412:septic tanks
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313:Installation
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235:Filter drain
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81:weeping tile
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63:filled with
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53:rubble drain
52:
48:
45:trench drain
44:
41:French drain
40:
38:
439:watercourse
428:federal law
422:Legislation
283:rain garden
250:groundwater
240:groundwater
158:geotextiles
108:septic tank
77:groundwater
49:blind drain
718:Categories
680:2006-08-23
629:2016-08-15
604:2023-10-08
562:2006-09-08
488:References
395:Other uses
341:improve it
209:geotextile
93:terracotta
85:drain tile
57:rock drain
345:verifying
269:Fin drain
167:Structure
744:Sewerage
724:Drainage
699:Archived
691:– US EPA
451:Dry well
445:See also
279:dry well
220:Variants
205:trencher
339:Please
147:⁄
118:History
95:tiles.
59:) is a
416:sewage
257:pipes.
124:France
65:gravel
61:trench
55:, and
33:gutter
674:(PDF)
667:(PDF)
281:, or
410:for
213:soil
154:soil
126:but
75:and
69:rock
343:by
87:or
67:or
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596:.
517:^
496:^
441:.
51:,
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364:(
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355:(
337:.
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Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.
