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Research about Long Island

Source-linked reports with geographic coverage including Long Island.

98 records · Page 6Linked to original sources

Ground-water levels and related hydrologic data from selected observation wells in Nassau County, Long Island, New York

Nassau County has experienced a rapid growth in population and industry in the past 20 years that has resulted in increased development of its ground-water resources. The county is located in west-central Long Island and its boundaries enclose a land area of 274 square miles. The climate is relatively mild and precipitation averages 43 inches a year. The precipitation is the ultimate source of natural replenishment to the ground-water reservoir. Ground water is found in the pore spaces of unconsolidated sands, gravels, and clays which overlay a basement of crystalline bedrock.

New York↗

Recent geologic studies on Long Island with respect to ground-water supplies

Recent studies have shown that relatively impermeable clay beds are widespread on Long Island but that erosion channels cutting through them permit restricted recharge of the underlying beds in some parts of the island. Of the more than 200,000,000 gallons of water a day now pumped from wells, about 65 per cent. comes from the surficial beds of Illinoian or Wisconsin age. Because of the restricted recharge of the lower beds and the desirability of saving these beds for use in localities where the upper beds may more easily be contaminated by salt water, any future large developments of ground water should be drawn from the surficial beds.

New York↗

Underground water resources of Long Island, New York

As Long Island is the largest island on the eastern coast of the United States, and is of such size, 120 miles long and 23 miles wide, that it is a more or less noticeable feature on even very small-scale maps, little need be said of its general geographic position.

New York↗