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The vast store of water beneath the ground surface has long been realized as an invaluable source of water for human consumption and use. Throughout the world, wells and springs fed by groundwater are revered for their life‐giving or curative properties (see Fig. 1.2), and utilization of groundwater long preceded understanding of its origin, occurrence and movement (Bord and Bord 1985).

Fig. 1.2 Lady's Well in Coquetdale, northern England (National Grid Reference NT 953 028). Groundwater seeping from glacial deposits at the foot of a gently sloping hillside is contained within an ornamental pool floored with loose gravel. The site has been used since Roman times as a roadside watering place and was walled round and given its present shape in either Roman or medieval times. Anglo Saxon Saint Ninian, the fifth‐century apostle, is associated with the site, and with other ‘wells’ beside Roman roads in Northumberland, and marks the spot where Saint Paulinus supposedly baptized 3000 Celtic heathens in its holy water during Easter week, 627 AD. The name of the well, Lady's Well, was adopted in the second half of the twelfth century when the nearby village of Holystone became the home of a priory of Augustinian canonesses. The well was repaired and adorned with a cross, and the statue brought from Alnwick, in the eighteenth and nineteenth centuries. Today, groundwater overflowing from the pool supplies the village of Holystone.

A holy or sacred well is commonly a well or spring at which religious devotions are, or have been, practised. In Ireland, for example, there are more than 3000 holy wells, many of which are sites of devotion, especially on the saint's day. Many of these wells have reputations for healing, with commonly cited cures being eye problems, toothache and warts (Misstear et al. 2018).

Springs are significant cultural places, embodying traditional folklore and mythology (Idris 1996; Park and Ha 2012; Powell et al. 2015) and supporting settlements along ancient trade routes (Aldumairy 2005). Indeed, the very survival and dispersal of early hominins, and later Homo, in the East African Rift System may have been influenced by springs. Hundreds of springs and groundwater‐fed perennial streams currently distributed across East Africa are likely to have functioned as persistent hydro‐refugia during dry periods of orbital‐scale climate cycles in the Plio‐Pleistocene and may have facilitated unexpected variations in isolation and dispersal of hominin populations (Cuthbert et al. 2017).

Evidence for some of the first wells to be used by modern humans is found in the far west of the Levant on the island of Cyprus. It is likely that Cyprus was first colonized by farming communities in the Neolithic, probably sailing from the Syrian coast about 9000 BC (Mithen 2012). Several Neolithic wells have been excavated from known settlements in the region of Mylouthkia on the west coast of Cyprus (Peltenberg et al. 2000). The wells are 2 m in diameter and had been sunk at least 8 m through sediment to reach groundwater in the bedrock. The wells lacked any internal structures or linings other than small niches within the walls, interpreted as hand‐ and foot‐holds to allow access during construction and for cleaning. When abandoned, the wells were filled with domestic rubbish which dates from 8300 BC, indicating that the wells had been built at or just before this date (Mithen 2012).

Wells from the Neolithic period are also recorded in China, a notable example being the wooden Hemudu well in Yuyao County, Zhejiang Province, in the lower Yangtze River coastal plain. Based on carbon‐14 dating of the well wood, it is inferred that the well was built in 3710 ± 125 BC (Zhou et al. 2011). The depth of the well was only 1.35 m with over 200 wooden components used in its construction comprising an outer part of 28 piles surrounding a pond, and an inner part, the wooden well itself, in the centre of the pond. The walls of the well were lined with close‐set timber piles reinforced by a square wooden frame. The 28 piles in the outer part of the site may have been part of a shelter for the well, suggesting awareness by the people of the Hemudu culture that their water source required protection (Zhou et al. 2011).

According to archaeological research, the Chinese are credited with developing the percussion method of well construction, a technique that has been in continuous use now for 4000 years. The ‘rope and drop’ method involved a steel rod or piston that was raised and dropped vertically via a rope supported by a bamboo framework. Using this percussion system with a heavy chiselling or crushing tool, wells were drilled to depths of 130 m around 3000 years ago, although construction took years to complete (Zhou et al. 2011). The cable tool drilling rig used today (see Section 7.2.2) is directly descended from the bamboo framework percussion drilling techniques developed in China.

Evidence for the appearance of dams, wells and terraced walls, three methods of water management, is widespread by the Early Bronze Age from 3600 BC, as part of what has been termed a ‘Water Revolution’ (Mithen 2012). The recognisable development of groundwater as part of a water management system also dates from ancient times, as manifest by the wells and horizontal tunnels known as qanats (ghanats) or aflaj (singular, falaj), both Arabic terms describing a small, artificial channel excavated as part of a water distribution system, which appear to have originated in Persia about 3000 years ago. Examples of such systems are found in a band across the arid regions extending from Afghanistan to Morocco. In Oman, the rural villages and aflaj‐supplied oases lie at the heart of Omani culture and tradition. The system of participatory management of communal aflaj is an ancient tradition in Oman by which common‐property flows are channelled and distributed to irrigation plots on a time‐based system, under the management of a local community (Young 2002).

Figure 1.3 shows a cross‐section along a qanat with its typical horizontal or gently sloping gallery laboriously dug through alluvial material, occasionally up to 30 km in length, and with vertical shafts dug at closely spaced intervals to provide access to the tunnel. Groundwater recharging the alluvium in the mountain foothills is fed by gravity flow from beneath the water table at the upper end of the qanat to a ground surface outlet and irrigation canal on the arid plain at its lower end (Fig. 1.4). The depth of the mother well (Fig. 1.3) is normally less than 50 m. Discharges, which vary seasonally with water table fluctuations, seldom exceeding 3 m³ s⁻¹.

Such early exploitation of groundwater as part of a sophisticated engineered system is also evident in the supply of water that fed the fountains of Rome (see Box 1.1). Less sophisticated but none the less significant, hand‐operated pumps installed in wells and boreholes have been used for centuries to obtain water supplies from groundwater found in surface geological deposits. The fundamental design of hand pumps of a plunger (or piston) in a barrel (or cylinder) is recorded in evidence from Greece in about 250 BC (Williams 2009). It is assumed that wooden pumps were in continuous use after the end of the Roman period, although examples are difficult to find given that wooden components perish in time. In Britain, the majority of existing hand‐operated pumps are cast iron, dating from the latter part of the nineteenth century (see Plate 1.1). Although entirely redundant now due to issues of unreliability in dry weather and the risk of surface‐derived pollution, private and domestic pumps were once widely used for supplying houses, farms, inns, almshouses, hospitals, schools and other institutions in cities, towns and villages. Ultimately, as mains water was introduced across Britain from the nineteenth century onwards following the Public Health (Water) Act of 1878, the village pump was superseded by the communal outdoor tap or water pillar, itself made redundant when piped water was provided to individual houses.

Fig. 1.3 Longitudinal section of a qanat (Beaumont 1968 and Biswas 1972).

(Sources: Based on Beaumont, P. (1968) Qanats on the Varamin plain, Iran. Transactions of the Institute of British Geographers 45, 169–179; Biswas, A.K. (1972) History of Hydrology. North‐Holland, Amsterdam.)

Fig. 1.4 Irrigation canal supplied with water by a qanat or falaj in Oman.

(Photograph provided courtesy of M.R. Leeder.)