View of a Johad at village Thathawata

View of a stepwell at Fatehpur, Shekhawati. This one featured in the movie Paheli

Rainwater harvesting is the gathering, or accumulating and storing, of rainwater. ^[1] Image File history File linksMetadata Size of this preview: 800 × 600 pixelsFull resolution (1152 × 864 pixel, file size: 172 KB, MIME type: image/jpeg) Image created by LRBurdak File history Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old version. ... Image File history File linksMetadata Size of this preview: 800 × 600 pixelsFull resolution (1152 × 864 pixel, file size: 172 KB, MIME type: image/jpeg) Image created by LRBurdak File history Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old version. ... , View of a Johad at village Thathawata View of children playing on sand dunes at village Thathawata Thathawata (Hindi: ठठावता, IAST: ) is a village located in Churu District of Rajasthan state in India. ... Image File history File links View of a Bawdi at Fatehpur Image by LRBurdak File history Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old version. ... Image File history File links View of a Bawdi at Fatehpur Image by LRBurdak File history Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old version. ... Fatehpur is a town of Sikar district in Rajasthan, India. ... Paheli (Devanagari: पहेली, Nastaliq: پہیلی, English: Riddle) is a Bollywood movie, released in India on June 24, 2005, directed by Amol Palekar and produced by Gauri Khan, Sanjiv Chawla and Shahrukh Khan, who also plays the male lead. ...

Traditionally, rainwater harvesting has been practised in arid and semi-arid areas, and has provided drinking water, domestic water, water for livestock, water for small irrigation and a way to replenish ground water levels. Sheep are commonly bred as livestock. ... Irrigation is the artificial application of water to the soil usually for assisting in growing crops. ... Groundwater is any water found below the land surface. ...

Use around the world

Currently in China and Brazil, rooftop rainwater harvesting is being practised for use for all the above purposes. Gansu province in China and semi-arid north east Brazil have the largest rooftop rainwater harvesting projects ongoing. Gansu (Simplified Chinese: 甘肃; Traditional Chinese: 甘肅; Hanyu Pinyin: ; Wade-Giles: Kan-su, Kansu, or Kan-suh) is a province located in the northwest of the Peoples Republic of China. ... This article or section does not cite any references or sources. ...

In Bermuda, the law requires all new construction to include rainwater harvesting adequate for the residents. The U.S. Virgin Islands has a similar law The United States Virgin Islands is a group of islands in the Caribbean that is a dependency of the United States. ...

In Indus Valley Civilization, Elephanta Caves and Kanheri Caves in Mumbai rainwater harvesting alone has been used to supply in their water requirements. Excavated ruins of Mohenjo-daro. ... , Bombay redirects here. ...

In Senegal/Guinea-Bissau, the houses of the Diola-people are frequently equipped with homebrew rainwater harvesters made from local, organic material. The Diola are a people living in The Gambia, Senegal (Casamance), and Guinea-Bissau. ...

In England water butts are oft-found in domestic gardens to collect rainwater which is then used to water the garden. For other uses, see England (disambiguation). ...

In Colorado, water rights laws severely restrict rainwater harvesting -- a property owner who captures rainwater is effectively stealing it from those who have rights to take water from the watershed.^[2] Official language(s) English Demonym Coloradan Capital Denver Largest city Denver Largest metro area Denver-Aurora Metro Area Area  Ranked 8th in the US  - Total 104,185 sq mi (269,837 km²)  - Width 280 miles (451 km)  - Length 380 miles (612 km)  - % water 0. ...

Advantages in urban areas

Rainwater harvesting in urban areas can have manifold reasons. To provide supplemental water for the city's requirement, to increase soil moisture levels for urban greenery, to increase the ground water table through artificial recharge, to mitigate urban flooding and to improve the quality of groundwater are some of the reasons why rainwater harvesting can be adopted in cities. In urban areas of the developed world, at a household level, harvested rainwater can be used for flushing toilets and washing laundry. Indeed in hard water areas it is superior to mains water for this. It can also be used for showering or bathing. It may require treatment prior to use for drinking. The hardness of the water results in a calcification Hard water is water that has a high mineral content (contrast with soft water), usually consisting of calcium (Ca2+) and magnesium (Mg2+) ions, and possibly including other dissolved metals, bicarbonates, and sulfates. ...

Two residences in the city of Toronto, Canada, use treated harvested rainwater for drinking water, and reuse water (i.e. treated wastewater) for all other household water applications including toilet flushing, bathing, showers, laundry, and garden irrigation (Toronto Healthy House).

In New Zealand, many houses away from the larger towns and cities routinely rely on rainwater collected from roofs as the only source of water for all household activities. This is almost inevitably the case for many holiday homes. 19th century Cottages in the small hamlet of Crafton, Buckinghamshire A cottage is a small house of any period. ...

Systems

There are many types of systems to harvest rainwater. The type used depends greatly on the purpose (domestic or industrial use) and to some extent also on physical and human considerations.

Domestic rainwater systems

System types

At the moment, 2 types of systems are generally used. These include homebrew systems and commercial systems. Both of these systems are known under the term water harvesters and require only a limited amount of knowledge to set up (if basic systems are used). In both cases, the system consists of a storage tank to store the water and piping (to guide the water in). Additionally, extra pressuring equipment as pressure vessels, inline pump controllers or pressure sensitive pumps may also be required. ^[3] Finally, water purifying equipment as water-purifying plants, UV-lights or distillation equipment are sometimes (depending on local conditions ^[4] ) added to purify the collected water. The system is then called a Greywater treatment system. Greywater systems are usually preferred over regular water harvesters as they allow the system to not only treat the rainwater, but water from other sources as well (eg the watercloset; if plants are used). However, this feature may also be averted by using a UV-lamp and composting toilet instead. See also: DIY Network, a cable TV network. ... Look up Commercial in Wiktionary, the free dictionary. ... A rainwater tank is a water tank which is used to collect and store rainwater runoff, typically from rooftops. ... // A tank is a container, usually for liquids, sometimes for gases. ... Steel Pressure Vessel A pressure vessel is a closed, rigid container designed to hold gases or liquids at a pressure different from the ambient pressure. ... For other uses, see Plant (disambiguation). ... Ultraviolet (UV) radiation is electromagnetic radiation of a wavelength shorter than that of the visible region, but longer than that of soft X-rays. ... Laboratory distillation set-up: 1: Heat source 2: Still pot 3: Still head 4: Thermometer/Boiling point temperature 5: Condenser 6: Cooling water in 7: Cooling water out 8: Distillate/receiving flask 9: Vacuum/gas inlet 10: Still receiver 11: Heat control 12: Stirrer speed control 13: Stirrer/heat plate... Greywater, sometimes spelled graywater, grey water or gray water and also known as sullage, is non-industrial wastewater generated from domestic processes such as washing dishes, laundry and bathing. ... Composting toilets use biological processes to deal with the disposal and processing of human excrement into organic compost material. ...

Depending on local circumstances however, a gravity-fed system may already be enough to have a pressured water collection system. ^[5] In the latter case, no pumps/pressure vessels are thus required to have a pressured system. In practice, gravity-controlled systems are usually created by placing the water harvester on an elevation (eg rooftops). Gravity is a force of attraction that acts between bodies that have mass. ... A rainwater tank is a water tank which is used to collect and store rainwater runoff, typically from rooftops. ...

DIY domestic systems

As water conservation is becoming more and more popular, more people have begun to make their own homebrew installation. These systems range from traditional technologies like rain barrels to more complex greywater systems. Through the internet, plans and accurate construction information have become available. ^{[6] [7] [8]} Depending on the degree of personal skill and preference, a more basic (regular water tank and piping) ^[9]) -or more advanced (eg pressured systems with water treatment, ...) -system is chosen.

Commercial domestic systems

Commercial systems are also made. They are offered by a variety of companies which include Rain Man, ... Commercial rain harvesters can be obtained in both pressurized ^[10] as gravity-fed systems ^[11]. Greywater treatment systems are sold by companies as Water Works UK, Nubian Water Systems, BRAC Systems, ... ^[12] Again, they are available in pressurised as gravity-fed systems.^{[13] [14]}

System's operation

A mechanism can be used to send the initial water flow to waste, usually the first few liters. These are commonly known as 'first-flush' diverters, and are used to increase the chance that the large-particle residue that might accumulate on your collection surface is washed away from (and not into) your storage tank. Such a system also compensates for the fact that the initial minutes of a rainfall can include airborne pollutants being washed from the sky^{[citation needed]}, and likewise minimizes contamination of your captured supply. Simple but regular inspection and maintenance of such a device is usually necessary. // A tank is a container, usually for liquids, sometimes for gases. ...

Not all catchment systems use such a feature. For example, rainwater in rural areas of Australia is traditionally used without such a system, and without treatment,^{[citation needed]} but this may be unwise in different environments.

Industrial systems

Rainwater may also be used for groundwater recharge, where the runoff on the ground is collected and allowed to be absorbed, adding to the groundwater. In US, rooftop rainwater is collected and stored in sump.^[15] In India this includes Bawdis and johads, or ponds which collect the run-off from small streams in wide area.^[16][17] Groundwater recharge is the practice of directing water - often rainwater, but sometimes reclaimed water - into groundwater aquifers. ... Groundwater is water located beneath the ground surface in soil pore spaces and in the fractures of lithologic formations. ... Bawdi or Bawri or Baodi is the local name of an architectural structure View of a Bawdi at Fatehpur traditionally constructed for storing water received from rainfall in parts of India particularly the arid regions of Rajasthan. ... View of a Johad at village Thathawata Johad (Hindi: जोहड) is a traditional pucca rainwater storage tank, mainly used for drinking purposes. ...

In India, reservoirs called tankas were used to store water; typically they were shallow with mud walls. Ancient tankas still exist in some places.^[18] See Waka (disambiguation) for other usages. ...

Quality

As rainwater may be contaminated, it is often not considered suitable for drinking without treatment. However, there are many examples of rainwater being used for all purposes — including drinking — following suitable treatment. Water purification is the process of removing contaminants from a raw water source. ...

Rainwater harvested from roofs can contain animal and bird feces, mosses and lichens, windblown dust, particulates from urban pollution, pesticides, and inorganic ions from the sea (Ca, Mg, Na, K, Cl, SO₄), and dissolved gases (CO₂, NO_x, SO_x). High levels of pesticide have been found in rainwater in Europe the highest concentrations occurring in the first rain immediately after a dry spell;^[19] the concentration of these and other contaminants are reduced significantly by diverting the initial flow of water to waste, as described above. The water may need to be analysed properly, and used in a way appropriate to its safety. In Gansu province, for example, harvested rainwater is boiled in parabolic solar cookers before being used for drinking.^{[citation needed]} In Brazil alum and chlorine is added to disinfect water before consumption.^{[citation needed]} Appropriate technology methods such as solar water disinfection, provide low-cost disinfection options for treatment of stored rainwater for drinking.this is very eco friendly for the earth. Horse feces Feces, faeces, or fæces (see spelling differences) is a waste product from an animals digestive tract expelled through the anus (or cloaca) during defecation. ... For other uses, see Moss (disambiguation). ... For other uses, see Lichen (disambiguation). ... Air pollution Pollution is the introduction of pollutants (whether chemical substances, or energy such as noise, heat, or light) into the environment to such a point that its effects become harmful to human health, other living organisms, or the environment. ... This article is about the electrically charged particle. ... For other uses, see Calcium (disambiguation). ... General Name, symbol, number magnesium, Mg, 12 Chemical series alkaline earth metals Group, period, block 2, 3, s Appearance silvery white solid at room temp Standard atomic weight 24. ... For sodium in the diet, see Salt. ... General Name, symbol, number potassium, K, 19 Chemical series alkali metals Group, period, block 1, 4, s Appearance silvery white Standard atomic weight 39. ... General Name, symbol, number chlorine, Cl, 17 Chemical series nonmetals Group, period, block 17, 3, p Appearance yellowish green Standard atomic weight 35. ... The sulfate anion, SO42− The structure and bonding of the sulfate ion In inorganic chemistry, a sulfate (IUPAC-recommended spelling; also sulphate in British English) is a salt of sulfuric acid. ... Carbon dioxide (chemical formula: ) is a chemical compound composed of two oxygen atoms covalently bonded to a single carbon atom. ... The term nitrogen oxide is a general term and can be used to refer to any of these oxides (oxygen compounds) of nitrogen, or to a mixture of them: Nitric oxide (NO), nitrogen(II) oxide Nitrogen dioxide (NO2) Dinitrogen monoxide (N2O) (Nitrous oxide) Dinitrogen trioxide (N2O3) Dinitrogen tetroxide (N2O4) Dinitrogen... Pick one: sulfur monoxide sulfur dioxide sulfur trioxide This is a disambiguation page — a navigational aid which lists other pages that might otherwise share the same title. ... A crystal of alum Alum, (IPA: ) a nonexistent compound that was imagined by Mary Daly, which serves no purpose than to supply highscool students with work. ... General Name, symbol, number chlorine, Cl, 17 Chemical series nonmetals Group, period, block 17, 3, p Appearance yellowish green Standard atomic weight 35. ... Appropriate technology is technology that is appropriate to the environmental, cultural and economic situation it is intended for. ... This article or section is in need of attention from an expert on the subject. ...

References

Bibliography

• Frasier, Gary, and Lloyd Myers. Handbook of Water Harvesting. Washington D.C.: U.S. Dept. of Agriculture, Agricultural Research Service, 1983
• Gould, John, and Erik Nissen-Peterson. Rainwater Catchment Systems. UK: Intermediate Technology Publications, 1999.
• Hemenway, Toby. Gaia’s Garden: A Guide to Home-Scale Permaculture. Vermont: Chelsea Green Publishing Company, 2000.
• Lowes, P. (1987). "The Water Decade: Half Time", in in John Pickford (ed.): Developing World Water. London: Grosvenor Press International, pp 16-17. ISBN 0-946027-29-3. 
• Ludwig, Art. Create an Oasis With Greywater: Choosing, Building, and Using Greywater Systems. California: Oasis Design, 1994.
• Pacey, Arnold, and Adrian Cullis. Rainwater Harvesting. UK: Intermediate Technology Publications, 1986.

External links

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Rainwater harvesting

• Rainwater Harvesting and Purification System - A case study is given to understand the basic process of collection and use of rainwater.
• Rainwater Harvesting Forum - This is a free and open forum for discussion of rainwater harvesting as alternative source of water for household, garden and rainfed farming needs.
• rwhdigest.com – Online digest promoting sustainable water management practices. Includes articles, case studies, discussion forum and instructions for establishing collection systems.
• Rainwater Harvesting for Drylands and Beyond - Contains resources for rainwater harvesting in the Southwestern United States and beyond.
• RWH on India Water Portal - India Water Portal has a comprehensive section on Rainwater Harvesting which includes case studies, courses, movies and policies.
• Rainwater harvesting System set-up information from Appropedia.
• Mywaterwisehome.com - Water sensitive design in a private Australian home. Builder is a PhD candidate researching household decision making to adopt decentralised pro-environmental technologies.
• Innovative Water Solutions, LLC - A residential and commercial rainwater harvesting system design/installation firm located in Austin, Texas.
• The rainwater glossaryInformation about and pictures of the components used in building a rainwater harvesting system - Australian content
• Water Storage: information about water Storage and other ecological systems for water supply, including rainwater harvesting
• Akash Ganga RWH - A starter site for India-centric RWH information.
• Harvesth2o.com – online rainwater harvesting community.
• Homeowner's guide to rainfall Instructional website for urban home-based rainwater harvesting.
• International Rainwater Harvesting Alliance (IRHA) International alliance created at the Johannesburg World Summit on sustainable development.
• International Rainwater Catchment Association (IRCSA) International organization on rainwater harvesting.
• Kedia R.W.H. Pattern – innovative methods and success stories
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• Rainwater Harvesting at Texas A&M University Extension
• [1] - CRS Ferrocement Water Tank Construction Manual.
• Rainwaterharvesting.org - Making water everybody's business.
• Appropedia:Rainwater - articles and project descriptions on Appropedia, the sustainability wiki, for project and how-to content.
• Australian Rainwater Industry Development group - an association for the promotion and development of innovation in rainwater harvesting.
• RAINfoundation.org Rainwater Harvesting Implementation Network : focuses on field implementation of small-scale rainwater harvesting projects
• Lakota Water Company - How Rainwater Collection Works - A simple graphical representation of how a rainwater collection system works.