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82-475: Stepwells (also known as vavs or baori ) are wells , cisterns or ponds with a long corridor of steps that descend to the water level. Stepwells played a significant role in defining subterranean architecture in western India from the 7th to the 19th century. Some stepwells are multi-storeyed and can be accessed by a Persian wheel which is pulled by a bull to bring water to the first or second floor. They are most common in western India and are also found in

164-447: A bit in a borehole . Drilled wells are usually cased with a factory-made pipe composed of steel or plastic. Drilled wells can access water at much greater depths than dug wells. Two broad classes of well are shallow or unconfined wells completed within the uppermost saturated aquifer at that location, and deep or confined wells, sunk through an impermeable stratum into an aquifer beneath. A collector well can be constructed adjacent to

246-533: A bath-like pond reached by steps is found at Uperkot caves in Junagadh . These caves are dated to the 4th century. Navghan Kuvo, a well with the circular staircase in the vicinity, is another example. It was possibly built in Western Satrap (200–400 AD) or Maitraka (600–700 AD) period, though some place it as late as the 11th century. The nearby Adi Kadi Vav was constructed either in the second half of

328-456: A caisson vertically below the top of the aquifer and then advancing lateral collectors out of the caisson and beneath the surface water body. Pumping from within the caisson induces infiltration of water from the surface water body into the aquifer, where it is collected by the collector well laterals and conveyed into the caisson where it can be pumped to the ground surface. Two additional broad classes of well types may be distinguished, based on

410-470: A circulation fluid to displace cuttings and cool bits during the drilling. Another form of rotary-style drilling, termed mud rotary , makes use of a specially made mud, or drilling fluid, which is constantly being altered during the drill so that it can consistently create enough hydraulic pressure to hold the side walls of the bore hole open, regardless of the presence of a casing in the well. Typically, boreholes drilled into solid rock are not cased until after

492-435: A confined space, it displaces oxygen, reducing oxygen concentration to a level low enough to pose a threat to humans and other aerobic organisms but still high enough for a risk of spontaneous or externally caused explosion. This potential for explosion is what poses such a danger in regards to the drilling and placement of water wells. Low levels of methane in drinking water are not considered toxic. When methane seeps into

574-686: A divination text of the Western Zhou dynasty (1046 -771 BC), contains an entry describing how the ancient Chinese maintained their wells and protected their sources of water. A well excavated at the Hemedu excavation site was believed to have been built during the neolithic era. The well was cased by four rows of logs with a square frame attached to them at the top of the well. 60 additional tile wells southwest of Beijing are also believed to have been built around 600 BC for drinking and irrigation. In Egypt , shadoofs and sakias are used. The sakia

656-550: A drilling action. Unlike rotary drilling, cable tool drilling requires the drilling action to be stopped so that the bore hole can be bailed or emptied of drilled cuttings. Cable tool drilling rigs are rare as they tend to be 10x slower to drill through materials compared to similar diameter rotary air or rotary mud equipped rigs. Drilled wells are usually cased with a factory-made pipe, typically steel (in air rotary or cable tool drilling) or plastic / PVC (in mud rotary wells, also present in wells drilled into solid rock). The casing

738-510: A freshwater lake or stream with water percolating through the intervening material. The site of a well can be selected by a hydrogeologist , or groundwater surveyor. Water may be pumped or hand drawn. Impurities from the surface can easily reach shallow sources and contamination of the supply by pathogens or chemical contaminants needs to be avoided. Well water typically contains more minerals in solution than surface water and may require treatment before being potable. Soil salination can occur as

820-743: A group of synthetic organofluorine chemical compounds that have multiple fluorine atoms attached to an alkyl chain. PFAS are a group of "forever chemicals" that spread very quickly and very far in ground water polluting it permanently. Water wells near certain airports where any form fire fighting or training activities occurred up to 2010 are likely to be contaminated by PFAS. A study concluded that of ~39 million groundwater wells 6-20% are at high risk of running dry if local groundwater levels decline by less than five meters, or – as with many areas and possibly more than half of major aquifers – continue to decline. Springs and wells have had cultural significance since prehistoric times, leading to

902-428: A leisure purpose alongside being main source of water for basic needs like bathing, washing clothes, farming, and watering animals. Stepwells also served as a place for social gatherings and religious ceremonies. Usually, women were more associated with these wells because they were the ones who collected the water. Also, it was they who prayed and offered gifts to the goddess of the well for her blessings. The well-water

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984-430: A pump. The water often comes from an aquifer or groundwater, and can be easily deepened, which may be necessary if the ground water level drops, by telescoping the lining further down into the aquifer. The yield of existing hand dug wells may be improved by deepening or introducing vertical tunnels or perforated pipes. Drawbacks to hand-dug wells are numerous. It can be impractical to hand dig wells in areas where hard rock

1066-433: A screening device, filter pack, slotted casing, or open bore hole is left to allow the flow of water into the well. Constructed screens are typically used in unconsolidated formations (sands, gravels, etc.), allowing water and a percentage of the formation to pass through the screen. Allowing some material to pass through creates a large area filter out of the rest of the formation, as the amount of material present to pass into

1148-406: A segmented steel drilling string, typically made up of 3m (10ft), 6 m (20 ft) to 8m (26ft) sections of steel tubing that are threaded together, with a bit or other drilling device at the bottom end. Some rotary drilling machines are designed to install (by driving or drilling) a steel casing into the well in conjunction with the drilling of the actual bore hole. Air and/or water is used as

1230-798: A temple or a shrine, it is either at the opposite wall of it or in front of the temple. Sindhvai Mata stepwell in Patan, Mata Bhavani stepwell in Ahmedabad, and the Ankol Mata stepwell in Davad serve as a great example of the stepwells that house shrines. The stepwell ensures the availability of water during periods of drought. The stepwells had social, cultural and religious significance. These stepwells were proven to be well-built sturdy structures, after withstanding earthquakes . Most places in India where there

1312-420: A variety of tools including electro-seismic surveying, any available information from nearby wells, geologic maps, and sometimes geophysical imaging . These professionals provide advice that is almost as accurate a driller who has experience and knowledge of nearby wells/bores and the most suitable drilling technique based on the expected target depth. Shallow pumping wells can often supply drinking water at

1394-904: A vertical shaft from which water is drawn and the surrounding inclined subterranean passageways and the chambers and steps which provide access to the well. The galleries and chambers surrounding these wells were often carved profusely with elaborate detail and became cool, quiet retreats during the hot summers. A number of distinct names, sometimes local, exist for stepwells. In Hindi -speaking regions, they include names based on baudi (including bawdi ( Rajasthani : बावड़ी ) , bawri , bawari , baori , baoli , bavadi and bavdi ). In Gujarati and Marwari language , they are usually called vav, vavri or vaav ( Gujarati : વાવ ). Other names include kalyani or pushkarani ( Kannada ), baoli ( Hindi : बावली ), barav ( Marathi : बारव ) and degeenar ( Bhojpuri : 𑂙𑂵𑂏𑂲𑂢𑂰𑂩). The stepwell may have originated during periods of drought to ensure enough access to

1476-571: A very important source of potable water in some rural developing areas, where they are routinely dug and used today. Their indispensability has produced a number of literary references, literal and figurative, including the reference to the incident of Jesus meeting a woman at Jacob 's well ( John 4:6) in the Bible and the " Ding Dong Bell " nursery rhyme about a cat in a well. Hand-dug wells are excavations with diameters large enough to accommodate one or more people with shovels digging down to below

1558-615: A very low cost. However, impurities from the surface easily reach shallow sources, which leads to a greater risk of contamination for these wells compared to deeper wells. Contaminated wells can lead to the spread of various waterborne diseases . Dug and driven wells are relatively easy to contaminate; for instance, most dug wells are unreliable in the majority of the United States. Some research has found that, in cold regions, changes in river flow and flooding caused by extreme rainfall or snowmelt can degrade well water quality. Most of

1640-648: A water supply, it is commonly referred to as "methane migration". This can be caused by old natural gas wells near water well systems becoming abandoned and no longer monitored. Lately, however, the described wells/pumps are no longer very efficient and can be replaced by either handpumps or treadle pumps . Another alternative is the use of self-dug wells, electrical deep-well pumps (for higher depths). Appropriate technology organizations as Practical Action are now supplying information on how to build/set-up ( DIY ) handpumps and treadle pumps in practice. Per- and polyfluoroalkyl substances ( PFAS or PFASs ) are

1722-693: Is a common problem with groundwater. Nitrates from sewage , sewage sludge or fertilizer are a particular problem for babies and young children. Pollutant chemicals include pesticides and volatile organic compounds from gasoline , dry-cleaning , the fuel additive methyl tert-butyl ether (MTBE), and perchlorate from rocket fuel, airbag inflators, and other artificial and natural sources. Several minerals are also contaminants, including lead leached from brass fittings or old lead pipes, chromium VI from electroplating and other sources, naturally occurring arsenic , radon , and uranium —all of which can cause cancer—and naturally occurring fluoride , which

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1804-404: Is abundant fresh water only during the monsoon season, stepwell and wells play a critical role in serving as a direct means to fresh water filtered through the earth. While the rivers, rivulets , creeks, and other natural water bodies dry up in this climate zone, stepwell and wells remain at a depth where there is less exposure to sun and heat. The majority of surviving stepwells originally served

1886-399: Is caused when the water table of the soil drops over time and salt begins to accumulate. In turn, the increased amount of salt begins to dry the soil out. The increased level of salt in the soil can result in the degradation of soil and can be very harmful to vegetation. Methane , an asphyxiant, is a chemical compound that is the main component of natural gas. When methane is introduced into

1968-437: Is constructed by welding, either chemically or thermally, segments of casing together. If the casing is installed during the drilling, most drills will drive the casing into the ground as the bore hole advances, while some newer machines will actually allow for the casing to be rotated and drilled into the formation in a similar manner as the bit advancing just below. PVC or plastic is typically solvent welded and then lowered into

2050-455: Is desirable in low quantities to prevent tooth decay , but can cause dental fluorosis in higher concentrations. Some chemicals are commonly present in water wells at levels that are not toxic, but can cause other problems. Calcium and magnesium cause what is known as hard water , which can precipitate and clog pipes or burn out water heaters. Iron and manganese can appear as dark flecks that stain clothing and plumbing, and can promote

2132-473: Is drilled to a predetermined depth or to a confining formation (clay or bedrock, for example), and then a smaller hole for the well is completed from that point forward. The well is typically cased from the surface down into the smaller hole with a casing that is the same diameter as that hole. The annular space between the large bore hole and the smaller casing is filled with bentonite clay , concrete, or other sealant material. This creates an impermeable seal from

2214-704: Is known to attract insects, animals, and many other germ breeding organisms. These stepwells, being a common space in frequent use by the inhabitants of the area, were considered to be a source of spreading epidemics and diseases. Many stepwells have ornamentation and details as elaborate as those of Hindu temples. Proportions in relationship to the human body were used in their design, as they were in many other structures in Indian architecture. Stepped ponds are very similar to stepwells in terms of purpose. Generally, stepped ponds accompany nearby temples while stepwells are more isolated. Stepwells are dark and barely visible from

2296-671: Is much more efficient, as it can bring up water from a depth of 10 metres (versus the 3 metres of the shadoof). The sakia is the Egyptian version of the noria . Some of the world's oldest known wells, located in Cyprus, date to 7000–8,500 BC. Two wells from the Neolithic period, around 6500 BC, have been discovered in Israel. One is in Atlit, on the northern coast of Israel, and the other is in

2378-600: Is present, and they can be time-consuming to dig and line even in favourable areas. Because they exploit shallow aquifers, the well may be susceptible to yield fluctuations and possible contamination from surface water, including sewage. Hand dug well construction generally requires the use of a well trained construction team, and the capital investment for equipment such as concrete ring moulds, heavy lifting equipment, well shaft formwork, motorized de-watering pumps, and fuel can be large for people in developing countries. Construction of hand dug wells can be dangerous due to collapse of

2460-477: Is simply hammered into the ground, usually with a tripod and driver , with pipe sections added as needed. A driver is a weighted pipe that slides over the pipe being driven and is repeatedly dropped on it. When groundwater is encountered, the well is washed of sediment and a pump installed. Drilled wells are constructed using various types of drilling machines, such as top-head rotary, table rotary, or cable tool, which all use drilling stems that rotate to cut into

2542-424: Is the fifth and the only king of all Maitraka kings connected with sun-worship. All other kings were followers of Shaivism . The copperplate grants do not help in identifying their origin, they describe only that the dynasty was born from a war-like tribe whose capital was at Vallabhi and they were Shaivas . Chinese traveler Hieun-Tsang visited Vallabhi during the second quarter of the 7th century had described

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2624-570: The Aram Bagh in Agra was the first Mughal garden in India. It was designed by the Mughal emperor Babur and reflected his notion of paradise not only through water and landscaping but also through symmetry by including a reflecting pool in the design. He was inspired by stepwells and felt that one would complement the garden of his palace. Many other Mughal gardens include reflecting pools to enhance

2706-576: The Cairo Citadel at 280 feet (85 m) deep and the Pozzo di San Patrizio (St. Patrick's Well) built in 1527 in Orvieto, Italy , at 61 metres (200 ft) deep by 13 metres (43 ft) wide are both larger by volume. Driven wells may be very simply created in unconsolidated material with a well hole structure , which consists of a hardened drive point and a screen (perforated pipe). The point

2788-508: The bacteria , viruses , parasites , and fungi that contaminate well water comes from fecal material from humans and other animals. Common bacterial contaminants include E. coli , Salmonella , Shigella , and Campylobacter jejuni . Common viral contaminants include norovirus , sapovirus , rotavirus , enteroviruses , and hepatitis A and E . Parasites include Giardia lamblia , Cryptosporidium , Cyclospora cayetanensis , and microsporidia . Chemical contamination

2870-710: The filtration of the contaminants of concern, and additional protection may be garnered by installing well-casing screens only at depths where contamination is not present. Wellwater for personal use is often filtered with reverse osmosis water processors; this process can remove very small particles. A simple, effective way of killing microorganisms is to bring the water to a full boil for one to three minutes, depending on location. A household well contaminated by microorganisms can initially be treated by shock chlorination using bleach, generating concentrations hundreds of times greater than found in community water systems; however, this will not fix any structural problems that led to

2952-444: The water table . The excavation is braced horizontally to avoid landslide or erosion endangering the people digging. They can be lined with stone or brick; extending this lining upwards above the ground surface to form a wall around the well serves to reduce both contamination and accidental falls into the well. A more modern method called caissoning uses reinforced concrete or plain concrete pre-cast well rings that are lowered into

3034-512: The 10th century or the 15th century. The stepwells at Dhank in Rajkot district are dated to 550–625 AD. The stepped ponds at Bhinmal (850–950 AD) are followed by it. The stepwells were constructed in the southwestern region of Gujarat around 600 AD; from there they spread north to Rajasthan and subsequently to the north and west India. Initially used as an art form by Hindus, the construction of these stepwells hit its peak during Muslim rule from

3116-560: The 11th to 16th century. One of the earliest existing examples of stepwells was built in the 11th century in Gujarat, the Mata Bhavani's Stepwell . A long flight of steps leads to the water below a sequence of multi-story open pavilions positioned along the east–west axis. The elaborate ornamentation of the columns, brackets and beams are a prime example of how stepwells were used as a form of art. The Mughal emperors did not disrupt

3198-728: The Jezreel Valley. Wells for other purposes came along much later, historically. The first recorded salt well was dug in the Sichuan province of China around 2,250 years ago. This was the first time that ancient water well technology was applied successfully for the exploitation of salt, and marked the beginning of Sichuan's salt drilling industry. The earliest known oil wells were also drilled in China, in 347 CE. These wells had depths of up to about 240 metres (790 ft) and were drilled using bits attached to bamboo poles. The oil

3280-461: The casing during construction and filling the casing annulus with an appropriate sealing material. The sealing material (grout) should be placed from immediately above the production zone back to surface, because, in the absence of a correctly constructed casing seal, contaminated fluid can travel into the well through the casing annulus. Centering devices are important (usually one per length of casing or at maximum intervals of 9 m) to ensure that

3362-717: The coast near modern Haifa in Israel . Wood-lined wells are known from the early Neolithic Linear Pottery culture , for example in Ostrov, Czech Republic, dated 5265 BC, Kückhoven (an outlying centre of Erkelenz ), dated 5300 BC, and Eythra in Schletz (an outlying centre of Asparn an der Zaya ) in Austria , dated 5200 BC. The neolithic Chinese discovered and made extensive use of deep drilled groundwater for drinking. The Chinese text The Book of Changes , originally

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3444-483: The contamination and generally requires some expertise and testing for effective application. After the filtration process, it is common to implement an ultraviolet (UV) system to kill pathogens in the water. UV light affects the DNA of the pathogen by UV-C photons breaking through the cell wall. UV disinfection has been gaining popularity in the past decades as it is a chemical-free method of water treatment. A risk with

3526-465: The culture that was practiced in these stepwells and encouraged the building of stepwells. The authorities during the British Raj found the hygiene of the stepwells less than desirable and installed pipe and pump systems to replace their purpose. A stepwell is generally located in two places - as an extension or part of a temple, and/or the outskirts of a village. When a stepwell is associated with

3608-522: The design and installation of private and municipal septic systems take all these factors into account so that nearby drinking water sources are protected. Education of the general population in society also plays an important role in protecting drinking water. Cleanup of contaminated groundwater tends to be very costly. Effective remediation of groundwater is generally very difficult. Contamination of groundwater from surface and subsurface sources can usually be dramatically reduced by correctly centering

3690-424: The drilled well, vertically stacked with their ends nested and either glued or splined together. The sections of casing are usually 6 metres (20 ft) or more in length, and 4 to 12 in (10 to 30 cm) in diameter, depending on the intended use of the well and local groundwater conditions. Surface contamination of wells in the United States is typically controlled by the use of a surface seal . A large hole

3772-434: The drilling process is completed, regardless of the machinery used. The oldest form of drilling machinery is the cable tool , still used today. Specifically designed to raise and lower a bit into the bore hole, the spudding of the drill causes the bit to be raised and dropped onto the bottom of the hole, and the design of the cable causes the bit to twist at approximately 1 ⁄ 4 revolution per drop, thereby creating

3854-525: The dynasty), who is associated with sun-worship , they were followers of Shaivism . Their origin is uncertain but they were probably Chandravanshi Kshatriyas . Following the decline of the Gupta Empire , Maitraka dynasty was founded by Senapati (general) Bhaṭārka, who was a military governor of Saurashtra under Gupta Empire, who had established himself as the independent around 475 CE. The first two Maitraka rulers Bhaṭārka and Dharasena I used only

3936-513: The formation, thus the term "drilling." Drilled wells can be excavated by simple hand drilling methods (augering, sludging, jetting, driving, hand percussion) or machine drilling (auger, rotary, percussion, down the hole hammer). Deep rock rotary drilling method is most common. Rotary can be used in 90% of formation types (consolidated). Drilled wells can get water from a much deeper level than dug wells can − often down to several hundred metres. Drilled wells with electric pumps are used throughout

4018-556: The foundation of towns such as Wells and Bath in Somerset . Interest in health benefits led to the growth of spa towns including many with wells in their name, examples being Llandrindod Wells and Royal Tunbridge Wells . Maitraka The Maitraka dynasty ruled the Kingdom of Valabhi in western India from approximately 475 to 776 from their capital at Vallabhi . With the sole exception of Dharapaṭṭa (the fifth king in

4100-427: The grouted annular space is of even thickness. Upon the construction of a new test well, it is considered best practice to invest in a complete battery of chemical and biological tests on the well water in question. Point-of-use treatment is available for individual properties and treatment plants are often constructed for municipal water supplies that suffer from contamination. Most of these treatment methods involve

4182-694: The growth of iron and manganese bacteria that can form slimy black colonies that clog pipes. The quality of the well water can be significantly increased by lining the well, sealing the well head, fitting a self-priming hand pump, constructing an apron, ensuring the area is kept clean and free from stagnant water and animals, moving sources of contamination ( pit latrines , garbage pits, on-site sewer systems ) and carrying out hygiene education. The well should be cleaned with 1% chlorine solution after construction and periodically every 6 months. Well holes should be covered to prevent loose debris, animals, animal excrement, and wind-blown foreign matter from falling into

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4264-416: The hole and decomposing. The cover should be able to be in place at all times, including when drawing water from the well. A suspended roof over an open hole helps to some degree, but ideally the cover should be tight fitting and fully enclosing, with only a screened air vent. Minimum distances and soil percolation requirements between sewage disposal sites and water wells need to be observed. Rules regarding

4346-635: The hole. A well-digging team digs under a cutting ring and the well column slowly sinks into the aquifer , whilst protecting the team from collapse of the well bore . Hand-dug wells are inexpensive and low tech (compared to drilling) and they use mostly manual labour to access groundwater in rural locations of developing countries. They may be built with a high degree of community participation, or by local entrepreneurs who specialize in hand-dug wells. They have been successfully excavated to 60 metres (200 ft). They have low operational and maintenance costs, in part because water can be extracted by hand, without

4428-551: The indigenous dynasty. Later readings corrected that Bhaṭārka was himself Maitraka who had succeeded in many battles. The earlier scholars had suggested the name Maitraka is derived from Mithra , the Sun or solar deity , and their supposed connection to Mihira and their sun-worshiping inclination . Though Mitra and Mihira are synonyms for the sun, the Sanskrit literature does not use it in sense of sun-worshipers. Dharapaṭṭa

4510-436: The landscape or serving as an elegant entrance. Other notable gardens in India which incorporate water into their design include: Azmi, Feza Tabassum. The ancient stepwells helping to curb India's water crisis , BBC Water well Wells have traditionally been sunk by hand digging, as is still the case in rural areas of the developing world. These wells are inexpensive and low-tech as they use mostly manual labour, and

4592-573: The location of over 1700 stepwells in Maharashtra. Delhi & Haryana : Gujarat : Karnataka : Kerala : Maharashtra : Rajasthan : Telangana : Uttar Pradesh : Stepwells from Mughal periods still exist in Pakistan . Some are in preserved conditions while others are not. Stepwells influenced many other structures in Indian architecture, especially those that incorporate water into their design. For example,

4674-527: The nominal allegiance to the Gupta overlords. He was succeeded by his son Dharasena II, who used the title of Mahadhiraja . His son, the next ruler Śilāditya I Dharmāditya was described by Hiuen Tsang , visited in 640 CE, as a "monarch of great administrative ability and of rare kindness and compassion". Śilāditya I was succeeded by his younger brother Kharagraha I. Virdi copperplate grant (616 CE) of Kharagraha I proves that his territories included Ujjain . During

4756-529: The other more arid regions of the Indian subcontinent , extending into Pakistan . The construction of stepwells is mainly utilitarian , though they may include embellishments of architectural significance, and be temple tanks . Stepwells are examples of the many types of storage and irrigation tanks that were developed in India, mainly to cope with seasonal fluctuations in water availability. A basic difference between stepwells on one hand, and tanks and wells on

4838-555: The other, is that stepwells make it easier for people to reach the groundwater and to maintain and manage the well. The builders dug deep trenches into the earth for dependable, year-round groundwater. They lined the walls of these trenches with blocks of stone, without mortar , and created stairs leading down to the water. This led to the building of some significant ornamental and architectural features, often associated with dwellings in urban areas. It also ensured their survival as monuments. A stepwell structure consists of two sections:

4920-678: The period when the Vallabhi kingdom declined in the 8th century AD. The Maitrakas were follower of the Shiva except Dhruvasena I who was Vaiṣnava and Dharapaṭṭa who was sun-worshiper. They all used title of parama-maheshwara before the names of king except those two. It is evident from the use of symbols like Nandi , the Bull and Trishula , the trident in their coins and inscriptions. There were presence of Vaishnavism and Goddess worship under their rule. There were large number of Buddhist Viharas in

5002-406: The placement of water wells is soil salination which occurs when the water table of the soil begins to drop and salt begins to accumulate as the soil begins to dry out. Another environmental problem that is very prevalent in water well drilling is the potential for methane to seep through. The potential for soil salination is a large risk when choosing the placement of water wells. Soil salination

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5084-410: The reign of the next ruler, Dharasena III, north Gujarat was included in this kingdom. Dharasena II was succeeded by another son of Kharagraha I, Dhruvasena II, Balāditya. He married the daughter of Harṣavardhana . His son Dharasena IV assumed the imperial titles of Paramabhattaraka Mahrajadhiraja Parameshvara Chakravartin . Sanskrit poet Bhatti was his court poet. The next powerful ruler of this dynasty

5166-419: The rule of Harṣa in the mid-7th century, but retained local autonomy, and regained their independence after Harṣa's death. When I-Tsing , another Chinese traveller, visited Vallabhi in the last quarter of the seventh century, he found Vallabhi as a great center of learning including Buddhism . Gunamati and Sthiramati were two famous Buddhist scholars of Vallabhi in the middle of the seventh century. Vallabhi

5248-714: The ruler as a Kshatriya. Later Mahayana Buddhist work Manju-Shri-Mula-Kalpa had described them as Varavatya Yadava. The late Jain traditional work Shatrunjaya-Mahatmaya of Dhaneshwara describes Śilāditya as the Yadavas of Lunar race . Virji concludes that Maitrakas were a Kshatriya of Lunar race and their origin was probably from Mitra dynasty which once ruled region around Mathura (now in Uttar Pradesh , India). Several scholars like Benerjee, D. Shastri, D. R. Bhandarkar agree with her conclusion. The Maitrakas ruled from their capital at Vallabhi . They came under

5330-478: The screen and the borehole or casing. This allows the water to be filtered of unwanted materials before entering the well and pumping zone. There are two broad classes of drilled-well types, based on the type of aquifer the well is in: A special type of water well may be constructed adjacent to freshwater lakes or streams. Commonly called a collector well but sometimes referred to by the trade name Ranney well or Ranney collector , this type of well involves sinking

5412-624: The sea, the kingdom had weakened considerably. The dynasty ended by 783 CE. Apart from legendary accounts which connect fall of Vallabi with the Tajjika (Arab) invasions, no historical source mention how the dynasty ended. More than hundred temples of this period are known, mostly located along the western coast of Saurashtra. Early scholars like Fleet had misread copperplate grant and considered Maitrakas as some foreign tribe defeated by Bhaṭārka. Bhagwanlal Indraji believed that Maitrakas were foreign tribe while Bhaṭārka, who defeated them, belonged to

5494-487: The structure can be lined with brick or stone as the excavation proceeds. A more modern method called caissoning uses pre-cast reinforced concrete well rings that are lowered into the hole. Driven wells can be created in unconsolidated material with a well hole structure, which consists of a hardened drive point and a screen of perforated pipe, after which a pump is installed to collect the water. Deeper wells can be excavated by hand drilling methods or machine drilling, using

5576-413: The surface to the next confining layer that keeps contaminants from traveling down the outer sidewalls of the casing or borehole and into the aquifer . In addition, wells are typically capped with either an engineered well cap or seal that vents air through a screen into the well, but keeps insects, small animals, and unauthorized persons from accessing the well. At the bottom of wells, based on formation,

5658-667: The surface, while stepped ponds are illuminated by the light from the sun. Stepwells are more linear in design compared to the rectangular shape of stepped ponds. A number of surviving significant stepwells in India : can be found across India, including in Rajasthan , Gujarat , Delhi , Madhya Pradesh , Maharashtra , and North Karnataka ( Karnataka ). In 2016 a collaborative mapping project, Stepwell Atlas, started to map GPS coordinates and collate information on stepwells, mapping over 2800 stepwells in India. Another project mapped

5740-458: The title of Senapati (general). The third ruler Droṇasiṁha declared himself as the Maharaja . During the reign Dhruvasena I, Jain council at Vallabhi was probably held. The next ruler Dharapaṭṭa is the only ruler considered as a sun-worshipper. King Guhasena stopped using the term Paramabhattaraka Padanudhyata along his name like his predecessors, which denotes the cessation of displaying of

5822-418: The use of the well: A water well constructed for pumping groundwater can be used passively as a monitoring well and a small diameter well can be pumped, but this distinction by use is common. Before excavation, information about the geology, water table depth, seasonal fluctuations, recharge area and rate should be found if possible. This work can be done by a hydrogeologist , or a groundwater surveyor using

5904-472: The water table falls and the surrounding soil begins to dry out. Another environmental problem is the potential for methane to seep into the water. Very early Neolithic wells are known from the Eastern Mediterranean . The oldest reliably dated well is from the pre-pottery neolithic (PPN) site of Kissonerga-Mylouthkia on Cyprus . At around 8400 BC a shaft (well 116) of circular diameter

5986-500: The water) were caused to be built. Numerous drinking-places were caused to be established by me, here and there, for the enjoyment of cattle and men. [But] this so-called enjoyment (is) [of little consequence]. For with various comforts have the people been blessed both by former kings and by myself. But by me this has been done for the following purpose: that they might conform to that practice of morality. The first rock-cut stepwells in India date from 200 to 400 AD. The earliest example of

6068-444: The water. The earliest archaeological evidence of stepwells is found at Dholavira where the site also has water tanks or reservoirs with flights of steps. Mohenjo Daro's great bath is also provided with steps on opposite directions. Ashokan inscriptions mention construction of stepwells along major Indian roads at a distance of every 8 kos (about 20.8 miles or 33.5 km) for the convenience of travellers, but Ashoka states that it

6150-515: The well bore, falling objects and asphyxiation, including from dewatering pump exhaust fumes. The Woodingdean Water Well , hand-dug between 1858 and 1862, is the deepest hand-dug well at 392 metres (1,285 ft). The Big Well in Greensburg, Kansas , is billed as the world's largest hand-dug well, at 109 feet (33 m) deep and 32 feet (9.8 m) in diameter. However, the Well of Joseph in

6232-400: The well slowly decreases and is removed from the well. Rock wells are typically cased with a PVC liner/casing and screen or slotted casing at the bottom, this is mostly present just to keep rocks from entering the pump assembly. Some wells utilize a filter pack method, where an undersized screen or slotted casing is placed inside the well and a filter medium is packed around the screen, between

6314-402: The world, typically in rural or sparsely populated areas, though many urban areas are supplied partly by municipal wells. Most shallow well drilling machines are mounted on large trucks, trailers, or tracked vehicle carriages. Water wells typically range from 3 to 18 metres (10–60 ft) deep, but in some areas it can go deeper than 900 metres (3,000 ft). Rotary drilling machines use

6396-406: Was a well-established practice which predated him and was done by former kings as well. King Devanampriya Priyadarsin speaks thus. On the roads banyan-trees were caused to be planted by me, (in order that) they might afford shade to cattle and men, (and) mango-groves were caused to be planted. And (at intervals) of eight kos wells were caused to be dug by me, and flights of steps (for descending into

6478-521: Was burned to evaporate brine and produce salt . By the 10th century, extensive bamboo pipelines connected oil wells with salt springs. The ancient records of China and Japan are said to contain many allusions to the use of natural gas for lighting and heating. Petroleum was known as Burning water in Japan in the 7th century. Until recent centuries, all artificial wells were pumpless hand-dug wells of varying degrees of sophistication, and they remain

6560-433: Was driven through limestone to reach an aquifer at a depth of 8 metres (26 ft). Well 2070 from Kissonerga-Mylouthkia, dating to the late PPN, reaches a depth of 13 metres (43 ft). Other slightly younger wells are known from this site and from neighbouring Parekklisha-Shillourokambos. A first stone lined well of 5.5 metres (18 ft) depth is documented from a drowned final PPN (c. 7000 BC) site at ‘Atlit-Yam off

6642-458: Was famous for its liberalism and the students from all over the country, including the Brahmana boys, visited it to have higher education in secular and religious subjects. We are told that the graduates of Valabhi were given higher executive posts. The Charanas of the region connect themselves with the last Maitraka ruler Śilāditya VI. Goddess Khodiyar is considered a contemporary figure of

6724-572: Was Śilāditya II. During the reign of Śilāditya V, Arabs probably invaded this kingdom. The last known ruler of this dynasty was Śilāditya VI. Maitrakas set up a Vallabhi University which came to be known far and wide for its scholastic pursuits and was compared with the Nalanda University . They came under the rule of Harṣa of Vardhana dynasty in the mid-seventh century, but retained local autonomy, and regained their independence after Harṣa's death. After repeated attacks by Arabs from

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