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NEW YORK STATE MUSEUM 



In. regard to Long Island water supplies, they may therefore be 

 considered in two lights: (1) There are numerous small brooks, 

 originating on the south slopes of the central riclge, which deliver 

 their waters to the Atlantic ocean; and (2) from the shallow 

 wells extending into the yellow gravel, already discussed. As to 

 the proper place for locating these wells, Professor Crosby con- 

 siders that the}' should be on a line along the south shore far 

 enough back from the sea to avoid the indraft of brackish sea- 

 water. The inclination of the water-bearing yellow gravel, with 

 its impervious floor of blue clay, is from the north towards the 

 south. The surface supplies from the brooks are none of them 

 very large. On the largest of them gristmills were established at 

 an early date, with ponds of from 8 to 40 acres of water surface 

 and from 5 to- 9 feet depth of water. These ponds were the 

 original water supply of Brooklyn. 



The fall at the dams rarely exceeds 8 feet. The original munic- 

 ipal water supply of the city of Brooklyn, as constructed about 

 1856 to 1859, had its source in the Hempstead plains, several of 

 the large brooks, flowing from the central ridge to the Atlantic 

 being appropriated for this purpose. A distributing reservoir was 

 established on the central ridge at an elevation of 170 feet above 

 tide, with the water of the brooks forced thereto by pumping. 

 These brooks were all mainly fed by springs delivering directly 

 into their ponds and channels. The length of these watercourses 

 from where the water was taken to the summer soui^es rarely 

 exceeds 4 miles. In the original construction the waters of these 

 ponds were conveyed by small branch conduits to a large main 

 conduit extending from the most easterly pond or reservoir to the 

 pump well at the engine house, which was located at the foot of 

 the ridge on which the Kidgewood distributing reservoir was 

 situated, not far from the east line of the city of Brooklyn. The 

 main conduit was so located that the water flowed to the engine 1 

 house by gravity. The following are the statistics of the six ponds 

 originally taken for the Brooklyn city supply, the minimum 

 deliveries here given being as ascertained by measurements dur- 

 ing the months of September and October, 1856 and 1857. The 

 figures represent the natural delivery of each stream at its lowest 

 stage of water, and do not include any encroachment upon the 

 stored water which each pond retained, when full. 



