A well is an excavation or structure created in the ground by digging, driving, or drilling to access liquid resources, usually water. The oldest and most common kind of well is a water well, to access groundwater in underground aquifers. The well water is drawn up by a pump, or using containers, such as buckets, that are raised mechanically or by hand. Water can also be injected back into the aquifer through the well. Wells were first constructed at least eight thousand years ago and historically vary in construction from a simple scoop in the sediment of a dry watercourse to the qanats of Iran, and the stepwells and sakiehs of India. Placing a lining in the well shaft helps create stability, and linings of wood or wickerwork date back at least as far as the Iron Age.
Wells have traditionally been sunk by hand digging, as is the case in rural areas of the developing world. These wells are inexpensive and low-tech as they use mostly manual labor, and 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 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 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 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.
Well history first starts around 8,000 years ago in China, Israel, and India. In India, the wells were known as step wells. This name is due to the steps leading down to the water. During the Neolithic era, Chinese workers hand-dug wells. These wells had rows of logs lining the inside with a square casing at the top. Those are a very basic version of the wells we have today. The deepest hand-dug well is in Brighton, East Sussex. It is 1,285 feet deep – as deep as the Empire State Building is tall. It took workers four years of working 24/7 to accomplish. They kept digging until they hit underground 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 was driven through limestone to reach an aquifer at a depth of 8 m. Well 2070 from Kissonerga-Mylouthkia, dating to the late PPN, reaches a depth of 13 m. Other slightly younger wells are known from this site and from neighbouring Parekklisha-Shillourokambos. A first stone lined well of 5.5 m depth is documented from a drowned final PPN (c. 7000 BC) site at ‘Atlit-Yam off 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 5090 BC, and Eythra in Schletz (an outlying centre of Asparn an der Zaya) in Austria, dated 5200 BC.
Some of the earliest evidence of water wells is located in China. The neolithic Chinese discovered and made extensive use of deep drilled groundwater for drinking. The Chinese text The Book of Changes, originally 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. Archaeological evidence and old Chinese documents reveal that the prehistoric and ancient Chinese had the aptitude and skills for digging deep water wells for drinking water as early as 11,000 to 12,500 years ago. 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 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 9000–10,500 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 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 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.
In 1808, the Ruffner brothers created a mechanical drilling machine. It was first used in Charleston, West Virginia to access water and salt from the Great Buffalo Lick. However, by the 1820s and 1830s, there is a new machine on the scene – the Auger Boring Machine. Subsequently, these machines for much deeper wells. They also protect the water from contamination thanks to the use of steel pipes. They were made from the first iteration of steel. Then, in 1908, Howard Hughes Sr. invented the roller cone drill bit. That led to rotary drilling technology to become the standard. That type of drill bit is still in use for many types of drilling today. Finally, in the 1940s, contractors invented portable drilling tools. That makes drilling much easier and that brings us to tools used today.
Contractors often drill modern drills with a drill rig on the back of a truck. There are still many ways to install wells. However, the most common installation method is to drill. Drilled wells require a drill rig. Contractors often mount drill rigs on trucks. Depending on the land where the well is being placed, different types of drill bits can be used. There are rotary drill bits that contractors use for chewing away at the rock. Percussion bits that smash the rock. If the ground is soft, use large auger bits. Drilled wells can be more than 1,000 feet deep. Wells that deep usually require a pump to ensure that water reaches the surface.
Types of Well Pumps
There are 3 major types of well pumps. The 3 types of well pumps are Shallow or Centrifugal pumps, Deep or Submersible pumps, and Convertible or Jet pumps.
Shallow pumps are as they sound. They are used in wells 25 feet deep or less. These pumps are typically found next to the well. They have a pipe that goes into the well then they generate enough suction to bring it into a home. Certainly, they are quite a reliable pump.
Deep pumps are used for depths typically around 100-300 feet. The difference between this pump and shallow or centrifugal pumps is that this one can be fully submerged. These pumps are typically the most popular form of well. They’re very strong and sturdy and need regular maintenance checks.
Jet pumps are known as convertible water pumps due to their versatility. They can be used up to 90 feet underground. As the name implies, jet pumps offer ‘jet power’ through the use of an ejector. This boosts the water pressure by creating a vacuum, pushing the water upwards at a faster and stronger pace. Jet pumps are very budget-friendly and powerful.
Society and Culture
Springs and wells have had cultural significance since prehistoric times, leading to 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.
Eratosthenes is sometimes claimed to have used a well in his calculation of the Earth's circumference; however, this is just a simplification used in a shorter explanation of Cleomedes, since Eratosthenes had used a more elaborate and precise method. Many incidents in the Bible take place around wells, such as the finding of a wife for Isaac in Genesis and Jesus's talk with the Samaritan woman in the Gospels.
Water is life, and safe drinking water is essential to human survival. A healthy natural environment ensures the sustainability of water and food sources, access to which is important for the well-being of human and animal communities.
In the Philippines, the “vitu” of Batanes is a built heritage in Batanes Islands that secured communal access to clean, fresh water and were in use until around the 1950’s. The “vitu” is one of the oldest water wells and in amazing preservation to boot. Locally called “vitu,” the earlier water wells of Batanes are unique from the old stone-paved wells that are common across the country. These vitu were dug down to as deep as about 20 meters to reach the freshwater level, since saline water penetrated the shallower levels. From mostly round mouths about 5-8 meters wide at ground level, these were made narrower towards the base, such that vertically, the wells are shaped like funnels or cones. All artistically done with some terracing, and all sides fortified by thick walling made of “hanaw” (igneous rocks) and coral stones that were carefully stacked with lime mortar like Ivatan houses, these could withstand natural calamities, particularly the strong typhoons that are typical to Batanes for much of the year.
What makes these structures even more distinct is that each comes with a stairway, with up to 75 steps, installed downwards through the bottom. Instead of the usual pail dropped down through ropes or levers in cylindrical wells, people had to take the stairs to collect water when it was not possible to do so from the rim. The stairway made the water more accessible to women and children, who were tasked to fetch for the household, especially when the water level went down in the dry months. Moreover, with the vitu filled to the rim during the rains, more people could collect water at the same time given its wide mouth.
Although much is yet to be explored about the reason for the vitu’s unique architecture, it is probable that the conical feature was a result of the way the excavation had to be made to reach the deep freshwater source. The massive stone pavement must have served both to prevent erosion and as filter especially for saline water. The stairways, moreover, could have been necessary to facilitate the periodical cleaning and maintenance of the wells as practiced until today by communities around the country that continuously depend on open wells for household use.
With accounts from elders who served as key informants, as well as ocular inspection conducted by the National Museum team, 17 of these unique vitu in the islands of Sabtang and Batan, including those that were already covered or converted into artesian wells, were measured, described, and photo-documented. Since that with 75 steps recounted by an elder is already covered, the deepest to be documented so far was the vitu with 47 steps in Sinakan, Sabtang, whose top portion is engraved with “1901”, possibly indicating the year of construction. Based on oral history, these structures are estimated to be 100-200 years old.
This vitu in Sitio Songsong, Brgy. Kayvaluganan in the town of Uyugan stand out among the unique, oldest wells of Batanes, as it has a perfect outline and intact structure.
These wells were said to be in use until the 1950's. Water pumps were introduced in Batanes in the early 1900's, and faucets began to be installed around the 1950's.
The inserted photo is that of the vitu with vegetation, grown as a result of abandonment.