FORESTS, RESERVOIRS, AND STREAM FLOW 303 
Taking everything into consideration on the most liberal basis, 
it is evident that this system cannot be built for less than $250 per 
1000000 cu. ft. The probable increase in the value of property to 
be condemned before the system could be built, and the present scale 
of prices of labor and material, make this figure a minimum. This 
would swell the cost of the whole system to more than four times Mr. 
Leighton’s estimate, or over half a billion dollars.* 
This is not all, however. It appears that the complete development 
of the reservoir system as proposed will take from industrial use probably 
1500000 acres of land, including the lands actually overflowed, the 
margins subject to damages, and sites for the dams and various 
structures appurtenant thereto. These lands will be in large part, 
by the very fact that they lie in valleys suitable for storage grounds, 
the best lands in the localities. Sooner or later they are bound to 
come into agricultural use, and with proper cultivation their annual 
net revenue value will be at least $5 per acre. If utilized for forest 
culture, they ought to yield 500 ft. B.M. of lumber and 1 cord of 
wood annually per acre. The value of the land for this purpose ought 
to be as great as the figures just given. It thus appears that the 
occupancy of these lands for reservoir purposes will take from the 
community an annual product of at least $7500 000 worth, and prob- 
ably more. 
The reservoirs will store about 2150 billion ecu. ft. of water. 
Assume that this can all be utilized for water-power, with the average 
head of 200 ft., giving theoretically about 1600000 h.p. per year, 
or 1280000 h.p. at 80% efficiency. At $5 per horse-power (the basis 
for this figure will presently be considered), the revenue from water- 
power will be $6 400 000, which falls short of the loss resulting from 
withholding the sites from productive use.t 
Viewed in the light of the foregoing exposition, the weakness of 
the reservoir scheme, as a measure of flood control or for improving 
navigation, is at once apparent. The question is: Will the ends justify 
*Recent examinations of certain sites, embracing nearly 70% of the proposed 
Moncngahela storage, indicate that the whole Ohio system will cost at least a billion 
dollars, and possibly a billion and a half. 
7The sanitary feature has not been considered, although it is one of some 
importance. The laying bare of large areas of reservoir bottoms in the heated 
portion of the year, is objecticnable, but it is not a matter affecting the element 
of cost. Neither is much stress here laid upon the danger to the reservoirs from 
silting up. This is not a region of heavy silt movement. In most of the reservoirs, 
the process will be very slow, and we may safely leave to distant generations the 
task of dealing with this problem whenever it reaches an acute stage. 
