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flood water by artificially recharging a confined aquifer would be comparable to an attempt on the part of a city to use the pipes of its distribution system as a storage reservoir. True, the artesian pressure would be increased around the area of artificial recharge so long as the injection of water were continued, and to this extent beneficial results would accrue, but these effects would dissipate rapidly whenever the injection were interrupted. Thus, if surplus water is available for recharge only intermittently, as durFIGURE 19.-Salty water in the Floridan aquifer.
Shaded area is that within which the water contains more than 1000 ppm
of chloride at moderate depths. This is almost as large as the area of artesian flow. At some places the water is only slightly salty and is being used for irrigation and municipal supply, but only because better water is lacking.
At other places the water is much too salty for all but a few unusual purposes. Some hydrologists think the salty water is a remainder of sea water that moved into the aquifer thousands of years ago when the sha stood higher
than today.
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FIG~tE19 Saty atr te Forianaquf..... Shadd ara isthatwithn whch te waer cntais ...e.thn.100.pp
of clorie atmodeate epth. Ths isalmot aslarg as.h..ae....ar tesin flw. A som plaes te waer s ony slghtl saly .n.i..ein. use for rrigtionand unicpal uppl, bt ony beausebettr w.er.i.lacing At oher lace thewate is uch oo slty or al bu a ..w.unsualpur poses.~ ~ ~ ~ ~ ~ ~ ~ ~~~~ ~... .oehd..i.stikte at ae i eanero e ae thatmove int th aqufer housndsof yars go wen he.s..sto..hghe
than........