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r'1tydR�ttepr tabYr� arett <br /> g t 2t f#^ .�-°Artesian swat <br /> 6 3 , <br /> P7HSSure fley:i#.d <br /> f C'e➢"1- � 6 µ ' s E <br /> „ s <br /> u <br /> r , <br /> e, r <br /> Water-table and confined (artesian) aquifers. <br /> WATER-LEVEL RISES <br /> The opposite problem, namely a rising water table, has developed in some parts of <br /> the country. Rising water tables occur in areas where pumpage has been curtailed after <br /> years of large ground-water withdrawals, such as for mine dewatering or municipal <br /> water supply, which kept the water table below its natural levels. The curtailment of <br /> pumping allows the water table to rise to the previous natural level, which may flood <br /> underground structures that were built when the water table was lowered. <br /> In many parts of the country, water levels in shallow aquifers have been lowered <br /> artificially over large areas. If houses are constructed in dewatered areas and if the <br /> water table then recovers to its natural (higher) level, basement flooding or foundation <br /> failures may occur, especially where the natural water level is within 10 feet of the land <br /> surface. Many basements that were built in a dry unconsolidated material and that had <br /> remained dry for decades have now become permanently wet. The public's first reaction <br /> may be that unusually heavy precipitation in the past few months has raised the water <br /> table or created a temporary perched-water system, when in fact the situation is much <br /> more serious and will remain a problem unless pumping is resumed to maintain a lower <br /> water table. <br /> Where water levels are closely monitored, water-level records can indicate whether <br /> such high water levels are related solely to climatic events or whether water levels are <br /> recovering after nearby pumping has ceased, An increasing number of local areas are <br /> being dewatered for mining or industrial uses, which could cause serious problems in the <br /> future when such pumpage is decreased or ended. <br /> Similar situations have occurred where housing developments were built during a <br /> period of extended drought when the water table was low, Even if basements were the <br /> "daylight" or raised type because the natural water table was shallow, the eventual <br /> return of a wet period caused the water table to rise a few feet and flood basements. <br /> [Source: USGS Publication by Roger M. Wailler; p. 3, pp. 12-13] <br /> htt us s. ov i w ruralhomeowner w ruralhomeowner new.html <br />