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Drought lower, and therefore more probw
<br /> lematic.
<br /> continued from page Al " If you have a relatively
<br /> recent drilled well, you're prob-
<br /> even though you might not ably going to be in good shape, "
<br /> detect any problem now, you Wilson said. " The caveat to that,
<br /> could have a real problem later of course, is that we don' t know
<br /> in the year. It's much better to how much longer this drought
<br /> take steps now to reduce that will go on . It could be years . But
<br /> risk . " what we ' re seeing so far are
<br /> Air gurgling from the faucet, problems with old bored wells,
<br /> slower flow, or no water are of which there are still a lot
<br /> signs the well may be going dry, mound .
<br /> he said. " In those few cases where we
<br /> Wells work by pumping water do have problems with drilled
<br /> to the surface from aquifers , wells, it 's usually because
<br /> which are layers of fractured there 's . some specific circum-
<br /> rock , sand or gravel , usually stance, like several wells com.
<br /> deep underground , that are per. peting for limited water in a
<br /> meated by water. Rainwater film localized area ,
<br /> tern down through the soil to Homeowners should be able
<br /> the aquifer — a process that can to tell what type well they have
<br /> take anywhere from days to mil- by a simple examination , Wilm
<br /> lennia , depending on geologic son said . Drilled wells typically
<br /> conditions— and fills in the have a 6- inch diameter pipe
<br /> cracks and spaces between the with a steel casing, he said ,
<br /> rock and soil particles . while bored wells are often two
<br /> When rainfall decreases for to three feet in diameter with a
<br /> long periods , as it has during concrete casing,
<br /> the current drought, the water In Orange County, the effect
<br /> table — the upper limit of the of the drought on wells depends
<br /> saturated layer — begins to. fall , on depth , age, location and
<br /> " The water table is drop. other variables, Holdway said .
<br /> ping, " said Nat Wilson, a hydro- The aquifer is not uniform
<br /> geologist with the N. C . Division throughout the county, and dif
<br /> of Water Resources. " It' s look- ferent tracts , even adjacent
<br /> ing for recharge, which comes ones , may have very different
<br /> from rainfall, and it isn' t getting levels of access to groundwater.
<br /> any. That's why stream flow is "There are places where you
<br /> so reduced; streams get most of can have two wells 40 or 50 feet
<br /> their water from groundwater apart, and you have completely
<br /> discharge, and when the water different flows, " Holdway said,
<br /> table drops too low you don' t get "It's extremely variable. But the
<br /> that. " bottom line is that the shallower
<br /> In periods of prolonged the well , the more impact the
<br /> drought, the water table can drought is going to have. "
<br /> drop below the intake of shal. Holdway said the county is in
<br /> low wells. When that happens, the process of implementing a
<br /> the tap runs dry. new computer program that
<br /> As a general rule, the deeper will track wells throughout the
<br /> the well , the less susceptible it county, identify those that go
<br /> is to drought. Like a straw in a dry and look for patterns in the
<br /> drinking glass , the amount of groundwater supply.
<br /> water a well can draw depends Residents with concerns or
<br /> on how deeply it reaches down questions about their well sys.
<br /> into the aquifer. tems, Holdway said, should call
<br /> Most newly drilled wells are Orange County Environmental
<br /> some 200 feet deep, Holdway Health Services at 245-2360 .
<br /> said . Older bored wells — or
<br /> even , in some cases , hand-dug Dave Hart can be reached at
<br /> wells — are considerably shal- 932-8744 or dhart@nando. com
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