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Ground water in the San Juan metropolitan area, Puerto Rico

January 1, 1976

Ground water in the San Juan, Puerto Rico, area has played a declining role in water supply since the completion of the Lofza reservoir project in the early 1950's. Ground-water potential is limited because of the small size of the aquifers and susceptibility to seawater intrusion. Of the 30 million gallons per day about half is being used. Two water-bearing zones are present: an artesian aquifer, composed of the San Sebastian Formation and the lower Cibao Formation that yields an average of 244 gallons per minute to wells; and, a water-table aquifer composed of the upper Cibao Formation and the Aguada and Aymamon Limestones that yields an average of 515 gallons per minute to wells. Ground water is less mineralized inland and in the artesian aquifer. Mean concentrations of dissolved solids are 363 milligrams per liter for the artesian aquifer and 525 milligrams per liter for the water-table aquifer. (Woodard-USGS)

Publication Year 1976
Title Ground water in the San Juan metropolitan area, Puerto Rico
DOI 10.3133/wri7541
Authors H. R. Anderson
Publication Type Report
Publication Subtype USGS Numbered Series
Series Title Water-Resources Investigations Report
Series Number 75-41
Index ID wri7541
Record Source USGS Publications Warehouse