HYDROLOGY OF NEW YORK 



181 



the streams issuing therefrom as to make water storage in New 

 York not only unnecessary but undesirable. In the case of the Hud- 

 son river there is perhaps 1500 square miles of the catchment area 

 within the Adirondack park, which, if entirely reforested, would, 

 as we have seen, increase the present flow of the stream iy 2 

 inches, but this increase of iy 2 inches is only obtained on the 

 1500 square miles actually reforested. The catchment area of 

 Hudson river above Mechanicville, the point where the gagings 

 shown in table No. 61 have been made, is 1500 square miles. The 

 net effect, therefore, at this point is only one-half inch of water, 

 distributed throughout the entire year, an effect which is inap- 

 preciable. 



However, there is another consideration. Owing to less rainfall 

 on the eastern plateau than on The northern plateau, streams in 

 the Catskill region do not flow as much as those in the Adiron- 

 dacks. As we have seen, the average flow of the Hudson river for 

 fifteen years is 23.27 inches. Taking the difference in rainfall 

 of these two districts at 4 inches, the flow of the streams in the 

 Catskill region, provided forestation were equal to that of the 

 Adirondaeks. would be over 10 inches. But taking into account 

 the existing differences in forestation, the flow of streams in the 

 Catskill region does not average over 16 or IT inches per year. 

 Tt follows, therefore, that an increase of 3y 2 inches in the Catskill 

 region is relatively of more value than a corresponding increase 

 in the Adirondack region. As has been shown, for the Adiron- 

 daeks the increase of iy 2 inches is equivalent to 6% per cent of 

 the present annual flow of streams issuing from that region, while 

 in the Catskills, 3y 2 inches is equivalent to 22% per cent of 

 the present annual flow of streams. Reforestation, therefore, 

 is considerably more valuable in the Catskills than it is in 

 the Adirondaeks. But the foregoing does not mean that 5 inches 

 more water will flow over the entire area of the streams 

 issuing from the Catskill region, but only from that portion 

 of the region on which forest has been restored. As we 

 have seen, the area of the proposed Catskill park is 703 square 

 miles, while the men of the Catskill Forest preserve is about 



