Page:Popular Science Monthly Volume 90.djvu/754

 Making Floods Work

How Water Users' Associations cooperate to utilize streams

��THE ideal river is one that has the same flow every day in the year. But, with rare exceptions, rivers do not flow that way. At one season of the year, the river runs bankful, or even over- flows and causes enormous damage and suffering. And then, a few months later, it is shrunken to a point where navigation is at a standstill, water power plants must shut down, water supplies are inferior and sometimes inadequate or unusable, and sewage and trade-wastes are so concen- trated in the scanty flow that a dangerous nuisance exists.

Regulating the flow of a river so that the water formerly wasted in flood times will be available during the dry weather' is a

��form of water conservation that has been very thoroughly developed in Germany, both as to the engineering works required and the necessary legal machinery to pro- vide for their construction and operation.

In the valleys of many of the German rivers, a large part of the waste water is stored in great reservoirs and let out dur- ing times of low water. It is thus changed from an agent of destruction to a benefaction to every com- munity in the valley.

There is nothing new in the idea of storing floods and using their waters dur-

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