146 REPORT OF INVESTIGATIONS No. 50
of lakes, and damage to property by the large fluctuation in the levels of certain lakes.
Draining excess surface water into the Floridan aquifer is beneficial if the water is not contaminated. When properly controlled, the practice increases recharge to the artesian aquifer, thereby tending to maintain ground-water levels and improve the quality of the ground water especially in the eastern part of the county. The need to develop methods of draining surplus water into underground storage without polluting or otherwise damaging the ground water should receive early consideration.
The problem of stabilizing lake levels is more complex than simply draining off water when levels are above average, because this often results in lower than usual levels during droughts. If abnormally low lake levels are to be avoided during droughts, water that has been removed to prevent high levels must be replaced or outflow from the lake must be reduced by a like amount.
Drainage of lake water to the sea during years of above average rainfall results not only in loss of water from the lake but also loss of ground water from the surrounding nonartesian aquifer. When the lake level is lowered the slope of the water table is steepened which causes more ground water to flow into the lake. Removal of this water results in less water in storage in the nonartesian aquifer to recharge the underlying Floridan aquifer and to maintain lake levels during droughts.
Droughts have caused no serious problems in Orange County in the past other than those associated with soil moisture deficiency and adverse affects on the appearance of lakes. As the county develops industrially, pressure to use its streams to remove wastes may increase. Most of the streams are either dry or have only small flow during droughts, so they cannot be used to remove wastes without becoming excessively polluted. The base flow of the streams can be increased by pumping water into them from ground sources or by deepening in areas where the water table is at or near the land surface during wet periods. However, perhaps a better solution would be to process waste so it will not pollute the water.
The availability of fresh water is a problem of increasing importance as Orange County and the east-central Florida region grow in population and industry. The amount of fresh water from rainfall within the region is large; but except for the many lakes in the western part of the region, suitable surface reservoirs are scarce. Fortunately, an enormous ground-water reservoir-the