Artesian well

Another large cost associated with incoming water is associated with its movement. Many aquaculture faciUties that utilize surface waters and those that obtain their water from wells other than artesian wells are required to pump the water into their faciUties. Pumping costs can be a major expense, particularly when the faciUty requires continuous inflow. 

Steig, m. path trail, -brunnen, m. artesian well. 

The confined type of aquifer has a hydraulic pressure (static head) that is on a higher level than the top of the aquifer. This artesian pressure can sometimes reach above the surface level resulting in self flowing wells (artesian wells). 

Figure 35. Flow of groundwater in an confined aquifer with potential artesian wells...

With the public dazzled by color and companies desperate to survive, factors such as clean air, pure water, and workers safety paled in importance. In a hasty pencil sketch of his family factory in England, Perkin drew one- or two-story buildings with tall brick chimneys and smoke blowing merrily out their tops. Water for the Perkins factory came from an artesian well, and waste was, no doubt, dumped in the handy canal. 

Fig. I. Ground cross section showing flowing artesian wells in a monocline...

Kuo, T.-L. (1968) Arsenic content of artesian well water in endemic area of chronic arsenic poisoning. Reports of the Institute of Pathology, National Taiwan University, 20, 7-13. 

The water in the saturated zone of the phreatic section of a confined system exerts a hydrostatic pressure that causes water to ascend in wells. In fact, a confined aquifer can often be identified by the observation that water ascends in a borehole to a level higher than the level at which the water was first struck. In extreme cases the water ascends to the surface, constituting an artesian well. This phenomenon of water ascending in a well and flowing by itself was first described in 1750 in the area of Artois, a province in... 

The level water reaches in an artesian well reflects its pressure, called the piezometric, or confined, water head (Fig 2.6). In boreholes drilled at altitudes that are lower than the piezometric head, water will reach the surface in a jet (or wellhead pressure) with a pressure that is proportional to the difference between the altitude of the wellhead and the piezometric head. The piezometric head is slightly lower than the water level in the relevant phreatic section of the system due to the flow resistance of the aquifer. Confined aquifers often underlay a phreatic aquifer, as shown in Fig. 2.7. The nature of such groundwater systems may be revealed by data measured in boreholes and wells. The water levels in wells 1 and 2 of Fig. 2.7 did not rise after the water was encountered, and both wells reached a phreatic aquifer. Well 3 is artesian, and the drillers account should include the depth in which the water was struck and the depth and nature of the aquiclude. The hydraulic interconnection between well 1 and well 3 may be established by... 

Artesian wells were grouped according to their <5D and 80 values and geographical distribution. Three such groups emerged (Table 9.4 and Fig. 9.25). 

The recharge altitudes of the three artesian well groups were determined with the aid of the altitude-isotopic composition... 

Fig. 9. 25 Isotopic data of artesian wells and springs in the Sperkhios Valley. Three well groups, or isotopic provinces, were recognized. A local meteoric line, <5D = 7<5lsO + 6, was established from the spring data. (From Stahl et al., 1974.)...

Table 9.4 Isotopically Deduced Average Recharge Altitudes for Artesian Well Groups in the Sperkhios Valley...

Fig. 11.8 14C ages (assuming initial concentration of 85pmc) of water samples from artesian wells near the south coast of South Africa as a function of the distance from the outcrop of water-bearing strata. (From Vogel, 1970.)... 

Artesian wells have been known from very early times, having been used by the Arabs, Chinese, and other ancient peoples, thousands of years ago. They are made by drilling through a hard, impervious stratum into a porous rock below, which may require up to 25 per cent. 

Chen, C. J., Chuang, Y. C., Lin, T. M., and Wu, H. Y., 1985, Mahgnant neoplasms among residents of a blackfoot disease-endemic area in Taiwan high-arsenic artesian well water and cancers Cancer Research, v. 45, p. 5895-5899. 

Artesian well A well in a confined aquifer in which the water rises above the top of the aquifer. 

Figure 83 Different geologic and topographic conditions that can result in artesian groundwaters. Artesian conditions require that there be a confining bed and elevated heads elsewhere in a groundwater recharge zone, (a) Shows elements of a "classical artesian system within a syncline. Artesian wells are shown in (b) stabilized sand dunes, (c) crystalline rock, (d) folded and fractured sedimentary rocks, (e) flat-lying sedimentary rocks, and (f) glacial sediments. From S. N. Davis and R. J. M, DeWiest. Hydrogeology. Copyright 1966. Used by permission.

Artesian wells are artificial springs, produced by boring in a low-lying district until a pervious layer l tween two impeinrious strata is reached the outcrop of the system being in an adjacent elevated region. 

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