The extent of bank revetment is, however, relatively so great when compared to the funds available for its construction that it has been necessary to confine the work to cases of urgent necessity, such as caving banks which threaten cut-offs or the safety of large levees which could only be replaced at excessive cost, and the harbor fronts of cities. Substantial revet ment for the purpose of fixing the banks of the river is essential to any successful scheme of improvement, and as the project adopted by Congress requires that the commission shall "correct, permanently locate and deepen the channel and protect the banks of the Mississippi River," large increase in expenditures for revet ment construction are urgently needed.
An important item in the operation of the commission is the construction and general re pair of levees, which was first authorized with out qualifying restrictions by the Act of 19 Sept. 1890; and since that date about one half of the appropriations made by Congress have been devoted to that purpose.
Briefly stated in general terms and quoting in part the several acts of Congress under which the project is being carried out, the work now in progress covers the Mississippi River from Rock Island, Ill., to the Head of the Passes, 1,568 miles, athe Ohio River from its mouth to the mouth of the Cache River," and "the Arkansas River between its mouth and the intersection thereof with the division line be tween Lincoln and Jefferson counties,* and it includes: 1. Flood protection by construction, extension, and repair of levees from Rock Island, ill., to Head of the Passes. 1.568 miles; along the Ohio River below the mouth of the Cache River and the Arkansas River up to the Lincoln-Jefferson County line, in co-opc:ation with the several States and levee boards, to "prevent destructive floods." 2. Continuation of improvement below the mouth of the Ohio River so as to "give safety and ease to navigation" of the Mississippi River at flood states by facilitating the inter change of traffic, "commerce, trade, and the Postal Service with a view to securing permanent channel depth of 9 feet" by means of: (a) Revetment of caving banks to "correct, permanently locate, and deepen the channel. and protect the banks of the
Mississippi River; and for the preservation of harbors and the security of levees.
(b) Dredging for the purpose of maintaining at all stages a "navigable channel 250 feet in width and 9 feet in depth." including construction, operation and maintenance of mutable dredge boats and auxiliary devices and appliances therefor.
3. The maintenance of a navigable channel between the waters of the Mississippi, Red and Atchafalaya rivers.
4. Physical investigations, maintenance of gauges and discharge measurements of the Mississippi River and its tributaries; preparation and publication of maps and physical data; surveys and investigations covering all phases of river regimen governing the work of channel improvement and flood control "from the headwaters of the River to the Head of the Panes." 5. Other miscellaneous details incident to the execution of the general project.
Since. the creation of the Mississippi River Commission in 1879 there has been appro priated and allotted for expenditure under it on the Mississippi River and its tributaries to 1917, $96,375,610.68.
Consult Anderson, A. D.,