212 CONSERVATION OF GROUND WATER 



water moves both from the north and from the south, and in 

 which there is considerable discharge from large springs. 



Studies prior to 1934 indicated that the canal must have 

 a low-water elevation as much as 40 feet above sea level in 

 order to prevent depletion of the ground-water reservoir. 

 On the other hand, construction of a lock canal across Flor- 

 ida would raise perplexing problems as to location, design, 

 and construction of locks. The limestone through which 

 the canal must pass is so permeable that extensive treatment 

 of foundations and abutments for all locks and dams would 

 be necessary, and geologic conditions at the proposed lock 

 sites were generally far from satisfactory. Accordingly it was 

 decided to construct a sea-level canal. 



A sea-level canal would intercept enormous volumes of 

 ground water and would lower the water table at the canal 

 by as much as 40 feet. Wide differences of opinion have 

 been expressed as to the area which would be affected by 

 this draining of ground water. Some reports state that the 

 effect would be limited to a zone extending 10 or 15 miles 

 on each side of the canal. On the other hand, ground-water 

 hydrologists have pointed out that if the canal were con- 

 structed water levels might well be lowered in a more ex- 

 tensive area; that the discharge of many springs near the 

 canal would probably be reduced; and that in some areas, 

 such as the celery-growing area in the vicinity of Sanford, 

 there would be danger of increasing salinity of water from 

 irrigation wells. Hydrologic studies far more detailed than 

 those yet made would be needed to determine quantitatively 

 the effect of the proposed canal upon the ground-water re- 

 sources. 



