PROBLEMS FROM DEVELOPMENT 131 



Water levels in wells declined as pumpage increased, and 

 in the various centers of heavy pumpage they reached posi- 

 tions 50 to 150 feet below sea level in 1942. Since reduction 

 of pumpage at Sparrows Point, water levels there have risen 

 50 to 100 feet, and in most districts today water levels are 

 within 75 to 90 feet of the land surface. In the past seven 

 years there has been little change in water levels in wells. 

 Closely spaced wells have drawn down the water level ex- 

 cessively at some points, and a more widespread distribu- 

 tion of pumping would result in higher pumping levels and 

 lower pumping costs. 



Few wells in the Baltimore area are now pumping water 

 entirely free from contamination, although most of the 

 water pumped is only slightly contaminated. The Baltimore 

 Harbor lies over part of the recharge area for the deeper 

 artesian aquifer, and pumpage has induced infiltration of 

 sea water until the water now pumped from wells in the 

 harbor area is about as saline as that in the harbor. Con- 

 tinued pumping removes this salt water and prevents it 

 from moving into well fields farther east which are not yet 

 seriously contaminated. The shallow aquifer is also over- 

 lain by salt water along the Patapsco estuary, and this salt 

 water has moved in as water levels declined below sea level, 

 contaminating shallow wells in the eastern part of Balti- 

 more. 



Part of the serious contamination of the shallow aquifer 

 is by sulfuric acid and copper sulfate from acid and metal- 

 refining plants that have been situated in this area at one 

 time or another during the past century. The acid water has 

 corroded the casings of many wells, leaked through them 

 into the deeper aquifer, and contaminated it locally. Many 

 abandoned wells may be responsible for contamination of 

 the deeper aquifer in this way. Some leaking wells have been 

 repaired by cementing, but in some instances water from the 

 shallow aquifer is pumped and wasted in order to prevent 

 it leaking into wells and contaminating adjacent deep wells. 



