Whatever its origin, groundwater spends a long time in an aquifer. It has time to dissolve minute quantities of minerals which can give it definite characteristics such as hardness or taste. It is often bottled and sold as mineral water. Groundwater is useful in many ways. It sustains the flow of rivers from which we take water for drinking and many industrial uses. And by sinking a well or borehole into an aquifer, groundwater can be pumped to the surface. The borehole can often be sited precisely where the water is needed-in a village or factory compound, for example- so avoiding the need for expensive water mains.
Rather than operate a borehole pump whenever water is needed, the usual arrangement is to pump water from the borehole at regular intervals to a tank or distribution reservoir on high ground or on top of a water tower. From here the water can flow by gravity to wherever it is needed. A distribution reservoir holds enough water to supply the area it serves for about a day.
Pumping water from an aquifer lowers the water table. This may reduce or stop the natural overflow from the aquifer, causing springs or small streams to dry up. At some places pumping from wells reduces the natural outflow. Some streams on chalk flow less than they used to do; in part this is the result of abstraction. People must decide which they value most-a cheap supply of water or preserving the countryside exactly as it was.
But some changes are blamed unfairly on abstraction. Earlier when there was still little pumping from the Chalk aquifer, water levels were low; low rainfall was the cause then. Although pumping out water can bring problems if aquifers do not have a chance to recharge, groundwater is such an enormous resource that it would be unthinkable to stop using it. But there is the cost of alternatives. On cannot simply build, nor afford to build enough reservoirs to replace the aquifers. Reservoirs provide a relatively small supply of water and they are expensive to build, but relatively easy to understand. Aquifers hold enormous amount of water but money has to be raised t build them up. In the light of increasing concern about the global warming it is better to have more understanding of water
Rather than operate a borehole pump whenever water is needed, the usual arrangement is to pump water from the borehole at regular intervals to a tank or distribution reservoir on high ground or on top of a water tower. From here the water can flow by gravity to wherever it is needed. A distribution reservoir holds enough water to supply the area it serves for about a day.
Pumping water from an aquifer lowers the water table. This may reduce or stop the natural overflow from the aquifer, causing springs or small streams to dry up. At some places pumping from wells reduces the natural outflow. Some streams on chalk flow less than they used to do; in part this is the result of abstraction. People must decide which they value most-a cheap supply of water or preserving the countryside exactly as it was.
But some changes are blamed unfairly on abstraction. Earlier when there was still little pumping from the Chalk aquifer, water levels were low; low rainfall was the cause then. Although pumping out water can bring problems if aquifers do not have a chance to recharge, groundwater is such an enormous resource that it would be unthinkable to stop using it. But there is the cost of alternatives. On cannot simply build, nor afford to build enough reservoirs to replace the aquifers. Reservoirs provide a relatively small supply of water and they are expensive to build, but relatively easy to understand. Aquifers hold enormous amount of water but money has to be raised t build them up. In the light of increasing concern about the global warming it is better to have more understanding of water
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