Geoscience Reference
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to subsurface. The distance between surface and water table in the coastal
area is very small, and the material is generally composed of sands, which
do not retain significant amounts of moisture under unsaturated conditions.
Hence, the irrigated water directly recharges to the unsaturated zone. The
distance between the water table and surface is at a minimum in the central
portion of the delta. It has been observed that areas of minimum depth from
the ground level to the water table have high freshwater potential whereas
lowering of the water table (Fig. 10(b)) from the ground surface reduces the
freshwater potential substantially. The water table elevation varies from 0.5
to 1 m from MSL and decreases gradually toward the coast.
Figure 12 shows the results in different environmental conditions due
to heavy and long rainy season and drought conditions due to high tem-
perature and less rainfall (climate change). Higher water table conditions
are observed due to heavy rain and irrigated water is recharged to the
Fig. 12. Simulated hydraulic heads of Godavari delta in different seasons (solid line in
heavy rainy season, - - - drought conditions).
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