WATER RESOURCES OF ORANGE COUNTY 85
Hiawassee well fluctuated about 16 feet. The hydrograph of the Hiawassee well is much smoother than the Bithlo well hydrograph, partly because the Hiawassee well is measured only once a month, whereas the Bithlo well has a continuous recorder and is plotted six times a month; but mostly because the water table is close to the land surface at the Bithlo well whereas it is 21 to 37 feet below the surface at the Hiawassee well. At Bithlo the water table reacts quickly to local showers and with prolonged rainfall quickly rises to the land surface where surface runoff occurs. During drought the water table quickly declines to a few feet below the land surface because surface drainage and evaporation can rapidly remove the water. However, once the water table is 3 or 4 feet below the surface, further decline is very slow because the streams have very shallow beds and cease to flow, evaporation practically ceases, and transpiration diminishes because most vegetation is shallow rooted. Also, lateral ground-water flow from the area is very slow because of the flat terrain; and downward leakage into the underlying artesian aquifer is slight because of the thick section of relatively impermeable marl and clayey sand that separates the nonartesian and the artesian aquifers.
At the Hiawassee well the water table is always 20 feet or more below the land surface. Rain filters slowly through the overlying sand, and the response of the water table to heavy rainfall or drought usually lags about a month. The water table fluctuations in this area reflect long periods of excessive and deficient rainfall. Brief showers after a dry period have little or no effect on the water table because the rain is held as soil moisture and returned to the atmosphere by evaporation and transpiration. However, the surface sands rapidly absorb even a heavy and prolonged rainfall and no surface streams flow from the area. The water that infiltrates below the root zone eventually seeps to the water table. After the water reaches the water table, it either seeps into nearby lowlying ponds (which occur to a considerable extent during periods of excessive rainfall) or it seeps downward into the artesian aquifer through the relatively thin and permeable clayey sand that separates the nonartesian and artesian aquifers. During droughts most of the ponds in the Hiawassee area go dry and the water table is mostly below the root zone, so it is apparent that further decline of the water table is due mostly to downward leakage into the artesian aquifer. The fluctuations of the water table in the Bithlo and Hiawassee wells reflect only natural changes as there is no appreciable pumping or irrigation in their vicinities.