Figure 30. The pattern of saltwater intrusion (salinities in parts 

 per million) of the Biscayne aquifer in the vicinity of Miami, 

 Florida (Source) Reference 87). 



1600 



I -40 - 



DISTANCE FROM BAY (FT) 

 800 



400 



Fi 

 ir 



V 



-100 



ties 



In the heavily industrialized areas around Galveston Bay, Texas, 

 particularly at the southern end of the Houston ship channel, extensive 

 land subsidence caused by excessive industrial groundwater withdrawal has 

 occurred. The subsidence rate has been increasing since the 1940's and 

 is predicted to continue. The bay area land has sunk as much as 8 feet 

 below sea level [89][90] (Figure 32). 



Subsidence increases the danger of flooding. Dikes have been 

 built and pumps installed to help ward off flooding problems from 

 subsidence. Unfortunately, such structural and technical protec- 

 tion measures treat only the "symptom" of unmanaged groundwater 

 pumping, i.e., the increase in relative sea level and flooding [89]. 



The solution is a groundwater management plan. Management would 

 include the entire equifer system since water withdrawal in one area 

 ultimately may affect the entire aquifer. The patterns and schedules 

 of recharge and extractions of water would be regulated. The manage- 

 ment program would specify the number and location of wells, their 

 pumping rates and annual limitations on total extractions. 



132 



