136 The Ohio Naturalist. [Vol. XIII, No. 7, 



"It is flying in tlie face of cold facts to contend any longer that reser- 

 voirs to retain the flood waters can not be built, or not without danger to 

 the entire valley below. The Ohio floods of 1907, the most disastrous for 

 more than two decades, were due to an excess of water estimated at 

 23,000,000,000 cubic feet. To hold every drop of that excess discharge 

 would have rec[uired a reservoir only a little more than half as big as the 

 Pathfinder irrigation storage reservoir on the North Platte River in Wyom- 

 ing, or one-third of the size of the reservoir in the Salt River project in 

 Arizona. The Engle dam on the Rio Grande, a hundred miles north of 

 El Paso, Texas, will impound about 120,000,000,000 cubic feet of water, 

 equal to one-sixtieth of the total annual discharge of the entire Mississippi 

 system, or more than five times the cjuantit}^ of water causing the most 

 destructive Ohio flood in a score of years. These reservoirs are being built 

 by the government at a cost of about $4,000,000 for the Pathfinder dam, 

 $5,300,000 for the Salt River project and $7,200,000 for the Rio Grande 

 reservoir. Furthermore, it is expressly stated by the Reclamation Service 

 that the Wyoming reservoir and the Engle dam will absolutley control the 

 worst floods which the North Platte and the Rio Grande have ever known, 

 the latter of these streams having been a notorious offender in flood dam- 

 age. The mere fact of being able to retain the flood waters in impounding 

 reservoirs can no longer be denied, nor can the claim of danger from break- 

 ing dams be now advanced as a valid argument against this system. This 

 government is most assuredly not spending millions in reclamation projects 

 and encouraging thousands of people to take up irrigated lands if there is any 

 remote likelihood of having homes, property and lives wiped out in floods 

 from bursting reservoirs. 



Granting, then, that the reservoirs are feasible, there still remains the 

 question of expense in constructing the number necessary to place one or 

 more in each of the most important tributaries. Estimate the expense most 

 generously, letting each one cost a third more than the Engle dam above 

 El Paso, and the total figure then is less than what has already been spent 

 on the Mississippi system. But there is another important factor to be 

 considered — the tremendous possibilities which lie in the development of 

 water power from each reservoir. The question of furtue motive power for 

 industrial purposes, as the coal supply decreases, is a problem which must 

 soon be met in this country, and probably will be solved by the use of water 

 power either directly or through electricity. In fact, even now, water 

 rights are being rapidly accjuired and developed on every hand, as the 

 advance guard of the change that is to come. A sample of what a storage 

 reservoir will do can be seen in the case of comparatively small irrigation 

 project at Minidoka, Idaho, which will develop about 30,000 horse power 

 per year. Renting this power at the very low figure of $10 per horse power 

 per year would pay for the entire Minidoka project, reservoir, irrigation- 

 canals, gates and all, in six years. The amount of power generated by the 

 Mississippi system is variously estimated high and low, with 60,000,000 

 horse power per year as an intermediate figure. Much of this amount is 

 not directly available, but granting on a conservative basis that a series 

 of impounding reservoirs would develop immediately 2 per cent of that 

 amount, there would be 1,200,000 horse power to be turned into electricity 

 and distributed to factories. A purely nominal rental would be ample 

 enough to repay in two or three decades the entire original expense of the 

 system, besides a good income on the investment. The reservoir system, 

 however, must be intimately associated with forest conservation as a vital 

 factor in regulating .surface drainage and in checking the amount of soil 

 erosion which sujjjjlies sediment to the river. 



The proper Iniilding of reservoirs in the headwaters, therefore, offers 

 what no other plan can possibly offer: it promises effective regulation of 

 river stages and water supply for all time to come, removing entirely the 



