HYDROLOGY OF NEW YORK 



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Lake Ontario 247 feet; and the St Lawrence river, from 217 to 

 about 100 feet above tide water. The cities and towns are mostly 

 situated in these several valleys along the streams. 



The quantity of pure upland water that can be furnished from 

 the six water centers is sufficient for 45,000,000 to 50,000,000 

 people, as may be shown by considering that the available areas 

 are more than 9000 square miles in extent. If we assume an 

 average collection of only 400,000 gallons per day from 9000 

 square miles and an average daily use throughout the State of 100 

 gallons per capita, we have water enough for 36,000,000 people, 

 and which could easily be increased by additional storage to a 

 supply sufficient for 45,000,000 to 50,000,000 people. 



On the accompanying map, the reserved elevated areas are con- 

 siderably in excess of 9000 square miles, but this is merely to 

 insure that no town or group of towns be required to go further 

 Than necessary for an upland water supply. These areas can 

 be reduced when definite information is at hand as to just where 

 the supply for each town or group of towns can be obtained. 



In order to emphasize the proposition that the main river val- 

 leys of the State should be kept clear for manufacturing, they 

 are generally excepted from the pure water reservations, shown 

 on the accompanying map. This map is subject to modification 

 in this particular on detailed study. 



The Adirondack center is a rugged region, consisting of primeval 

 crystalline rocks, covered locally with sand areas. Here appeared 

 some of the first dry land on the western continent, and thus 

 was laid, in early geologic time, the basis of those fine river sys- 

 tems which, issuing from this water center, have created water 

 resources of vast value to the citizens of New York. From this 

 center water may be supplied to Plattsburg, Malone, Canton, Pots- 

 dam, Ogdensburg, Utica, Herkimer, Johnstown, Saratoga Springs. 

 Schenectady, Lake George, Albany, Troy and many other large 

 towns of the region, all within practical distance of the purest 

 water, flowing from granitic catchments. This region is also 

 extensive enough to furnish abundant supplies to the cities of the 

 Hudson valley, including the City of New York. 



The geologic history of Catskill and Allegheny water centers is 

 quite different from that of the Adirondack center. In both these 

 regions the sedimentary sandstone rocks of the Chemung and Cats- 



