FOBEST LANDS FOE THE PROTECTION OF WATERSHEDS. 81 



The caving of the banks of our great rivers is constantly cited as an example 

 of soil loss on an enormous scale, and it is asserted that this condition is worse 

 now than formerly. The Mississippi and Missouri rivers, practically alike in 

 this respect, are the two most prominent examples. The author will consider 

 briefly the case of the Missouri because he has had a long and intimate acquaint- 

 ance with that stream from its mouth to its source. 



It may be stated by way of refutation that the actual condition of this stream 

 to-day is better thau before settlement began in its valley, except that possibly 

 the low-water flow is slightly diminished to meet the demands for irrigation. 

 The stream is not "constantly becoming more and more savage," as a recent 

 writer asserts. On the other hand, its natural savagery is much restrained. 

 Probably 100 miles of its banks are protected ; snags and drift heaps are largely 

 removed; considerable bottom land has been reclaimed and turned to indus- 

 trial use; floods are no greater than they used to be, and navigation is safer 

 and easier. Navigation has ceased, not because the river has deteriorated, as is 

 commonly asserted, but because the natural difficulties peculiar to this stream 

 are so great and so hard to overcome that boats can not live and do business 

 -at the same rates at which railroads transport freight. 



That the river is a most destructive one to the bottom lands along its course 

 is only too true; but the character of its destructive work is generally misun- 

 derstood. The writer just quoted states that the river carries away annually 

 8,000 acres of bottom land within the limits of the State of Missouri alone. 

 The total acreage of these lands is about 640,000. If this statement were true, 

 more than the entire area would have been carried away since the voyage of 

 Lewis and Clark, and if the process had been continuous since Columbus dis- 

 covered America the river to-day would be flowing in its original channel in 

 the solid rock, 75 to 90 feet below the present surface. As a matter of fact, 

 there is more soil in the valley to-day than there was at the date of either of 

 these 'events. Taking an average for a considerable period, none of the bottom 

 land is lost. It has always been slowly rising through accretion. The bank 

 caving is only a transfer from one point of the shore to another. For every 

 dissolving bank there is a nascent bar. Where steamboats ran last year wil- 

 lows may be growing this, and next year the farmer may be planting his corn. 

 The havoc wrought concerns the individual owner, but not the valley bottom 

 itself. The cruel losses attract attention ; the unobtrusive gains do not ; but the 

 account always balances itself. The' harm done is first to the individual whose 

 possessions are swept away, and second to the community through paralysis of 

 development, depreciation of values, and the holding back of this natural garden 

 spot from becoming what it ought to be. The evil is a very real one, and the 

 author has long endeavored, though without success, to secure provision in the 

 river and harbor bill for its amelioration. Great as the evil is, however, it is 

 not at all in the nature of an actual loss of land to the valley. 



It must be clear from the foregoing that the bottom lands of the Missouri add 

 nothing whatever to the total quantity of sediment that passes out of the mouth 

 of the stream, for these bottoms have been increasing rather than diminishing 

 in quantity. Likewise, the Mississippi bottoms contribute nothing to the volume 

 of sediment that is carried into the Gulf of Mexico. It all comes from the 

 uplands, far and near, but principally from the more remote and hilly regions. 

 This load is in the nature of through traffic. The local freight picked up from 

 a caving bank is mostly discharged at the next station. It follows, therefore, 

 that if the banks of these streams were revetted from the Gulf to Pittsburg, the 

 Falls of St. Anthony, and the mouth of the Yellowstone, the quantity of sedi- 

 ment passing into the Gulf would not be diminished a particle. Such revetment 

 would nevertheless be of the very highest value, if it could be made to hold, for 

 it would give permanence to the banks, security to riparian property, and would 

 largely prevent bar building by training the river into a regular channel and 

 relieving it of everything except its through load of sediment. 



The bank-caving problem of these valleys is unaffected in any appreciable 

 degree by the influence of forests or culnvation on the watersheds, and can not 

 be solved or materially assisted by any practicable changes in these conditions. 

 The problem is strictly a local one, and the remedy must be a local one. Even 

 if it were possible to bring the waters down from the uplands perfectly clear, it 

 is not at all certain that the effect upon the bottom lands would not be injurious 

 rather than beneficial ; for then the caving soil, instead of being quickly depos- 



Transactions American Society of Civil Engineers, Vol. LIV, p. 336. 

 72538 AGB 09 6 



