CHAPTER II. 

 REGULARIZATION. 



Theory. In a stream in a natural state there is a constant change going on. The 

 banks are being cut away, bars are forming, channels are dividing, and the bed is 

 shifting. In looking for a remedy the idea is naturally suggested of building artificial 

 banks and thus modifying the regime of the river. The contraction thus effected will 

 accelerate the current, and a new and controllable direction will be given to the 

 water, so that it may be expected that a more uniform condition of the stream 

 will be brought about. Thus is conceived the possibility of securing a better water- 

 way than the original, and one which will be exempt from many of the evils existing 

 in rivers in their natural state. In this natural state there exists a series of pools and 

 shoals. In the pools there is ample depth for navigation, but at the shoals the water 

 spreads out into a superficial sheet, and to secure and maintain a navigable depth this 

 must be confined to narrower limits by structures built in the bed of the stream. 



General. Regularization, or regulation as it is sometimes called, has been applied 

 in Germany on a very extensive scale, and has been employed in all countries to a 

 considerable extent. It has for its object the establishment of a bed for ordinary 

 and low-water stages, and the equalization of the slope. To this is sometimes added 

 the duty of protecting the banks above these stages. Its comparatively low cost and 

 the rapidity with which the works can be put into execution have recommended it 

 for rivers of great length and fall, where canalization would have been out of the 

 question on account of the expense and the length of time required to construct the 

 works, so that hundreds of miles of river have been rendered navigable where, without 

 this system, commerce would now be impossible, or, at least, very uncertain. In 

 many cases, in fact in the majority in this country, the work of regularizing is incom- 

 plete, having been applied only at those points giving most serious trouble to navigation. 

 The conditions originally existing have been greatly improved by a general cleaning 

 of the channel, followed by works of contraction and correction here and there, having 

 in view the concentration of the river at low stages to a single bed, the deepening of 

 the water, and its guidance in more uniform widths; and the banks have been protected 

 at many of the places where most seriously menaced. However, very little of this 

 work is complete, and it will require large additions and extensions before the .desired 

 results are obtained. In fact much of it has been experimental in character, and 

 many of the failures have been due to the lack of an extended study of the existing 



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