92 HAUPT — THE MISSISSIPPI KIVER PROBLEM. [Feb. 19, 



and out of the highway of commerce, which must otherwise be 

 carried to the Gulf and be dropped directly across the channel, thus 

 extending the trough, reducing the slope and increasing the height 

 of the floods. In fact a former Chief Engineer of the State of 

 Louisiana stated that the reason for selecting the Southwest Pass for 

 improvement was because of its greater general depth, so that the 

 shoaling which must result from the extension of the channel four 

 miles by the two jetties would not so soon affect the navigable 

 depths, in consequence of the contraction of the outlet. 



As already stated, similar results have taken place in the South 

 Pass above the jetties, where the fill in one place has exceeded forty 

 feet. But these lateral outlets also play an important part in the 

 reclamation of land, as well as in reducing floods and improving 

 navigation, for by this method of hydraulic grading, without cost, 

 large areas are gradually filled and converted into valuable planta- 

 tions. The extent of these deposits may be roughly determined by 

 a comparison of the United States Coast Survey charts of 1854 and 

 1884, from which it appears that the accretion to the land above 

 water in the vicinity of the Bayou Grand Liard, Spanish Pass, Red 

 Pass, Tiger Pass, Grand and William's Passes during the thirty years 

 between the surveys amounted to about 113 square miles, or nearly 

 75,000 acres. At Cubit's Gap, where the river is straight and 

 wide, the rate of deposit has also been considerable. This breach 

 occurred in 1863, and within a few years an area of about eight 

 square miles was raised above water ; while a survey made by a Mr. 

 Chucas Lewis in 1892 showed further deposits covering some forty- 

 two square miles, which is already laid out (on paper), under the 

 Government land system, into townships and sections. 



A better idea of the extent of this contribution to the wealth of 

 the nation may be obtained by computing the cost of securing it by 

 the usual method of back-filling by the use of hydraulic dredging 

 at, say, ten cents per cubic yard, and assuming the average depth to 

 be nine feet. On this basis the total fill would aggregate some 

 400,000,000 cubic yards in the thirty years, or over 13,000,000 

 cubic yards per year. The total cost of securing this result by 

 dredging, regardless of time, would therefore represent ^40,000,000 

 for this one crevasse. 



At '' The Jump," where 113 square miles were reclaimed in about 

 thirty years, the cost would have been ^3,530,000 per annum if 

 attempted by mechanical dredging, or ^105,000,000 for the entire 



