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lachian Mountains on the east. And the lower Mississippi River has to take care of all the water after it gets there. Is that right? General CRAWFORD. Yes, sir.
The CHAIRMAN. We will be glad to have your statement covering the situation with respect to the lower Mississippi River. You may proceed. .
widened is more above the rt stretch: Francis Bng Little mit
STATUS OF PROJECT, FLOOD CONTROL, MISSISSIPPI RIVER AND TRIBUTARIES
General CRAWFORD. The project for flood control, Mississippi River and tributaries, begins at the Little River diversion just above the Commerce Hills on the west bank of the river a few miles south of Cape Girardeau, Mo. The actual top of the levee along Little River diversion which protects the head of the St. Francis Basin, is above the 1941 grade except for a very short stretch. The 1941 net grades, however, are about 1 foot above the 1928 net grade on about 15 miles of this levee. As more urgent work and funds permit, its crown will be widened to the new 25-foot width, and an impervious facing added to its riverside slope.
Beginning at the lower end of the Commerce Hills, the levee protecting the upper St. Francis Levee District follows the right bank of the river to Birds Point, Mo., opposite Cairo, where the Birds Point-New Madrid floodway begins. The levee above Birds Point has been brought to full project dimensions. Between Birds Point and New Madrid the river-bank levee remains according to plan at 1914 grade. Existing law provides that about 10 miles at the upper end be degraded about 3 feet to correspond to 55 feet on the Cairo gage so as to admit flow automatically into the floodway at that stage. The degrading has not yet been undertaken. The floodway has been used once, namely, in 1937, at which time the water entered by way of natural, and later, by way of artificial crevasses. The planned capacity of the floodway was approximately 450,000 cubic feet per second for the project flood. In 1937 it carried from 210,000 to 670,000 cubic feet per second at various points along its course, flow entering at a number of crevasses downstream from the fuse plug.
The floodway which averages about 5 miles in width, is bounded on the west by the Birds Point-New Madrid set-back levee 34.5 miles in length, which has been brought to full project grade and cross section throughout.
The west-bank levee system is interupted at New Madrid by St. Johns Bayou. It resumes on the high ground of Sikeston Ridge and is continuous thence throughout the remainder of the St. Francis Basin, a distance of 227.8 miles to the mouth of the St. Francis River near Helena, Ark.
The lower 26 miles of this levee line, in the St. Francis backwater, do not require enlargement to the 1941 grade. Of the remaining 202 miles, 7612 miles have already been enlarged, 14 miles are under contract for enlargement, and 44 miles are scheduled for enlargement this coming season, comprising 11.8 miles from New Madrid to Point Pleasant, Mo.; work near Caruthersville, 4 miles; near Cottonwood Point, 4 miles and 24 miles extending about equal distances above and below West Memphis. Above the St. Francis backwater 13 miles of levee require no raise in levee grade. This leaves about 541,2 miles to
be enlarged following the next fiscal year. The work will be required between Sikeston Ridge and New Madrid; Point Pleasant and Missouri-Arkansas State line and from below Memphis to a point about opposite Hughes, Ark.—at an estimated cost of about $3,000,000.
After its interruption by the St. Francis River and Crowleys Ridge, the west-bank levee resumes on high ground above Helena, Ark., extends thence along the water front at Helena, and continues uninterruptedly to the mouth of White River where it loops to form the Laconia Circle. This stretch of levee is 74 miles in length. The 1928 and 1941 net grades on the upper 54 miles are identical, but about 51/2 miles of this stretch, in the former backwater area, have not been enlarged to the present approved cross section. The status of the remaining 20 miles is as follows: Two miles have been completed to the 1941 grade, about 412 miles are scheduled for construction under the fiscal year 1947 program, the remaining 1312 miles will have to be enlarged with future appropriations at an estimated cost of about $800,000.
The White River backwater levee connects with the Laconia Circle levee and extends upstream along White River, looping back to join the main Mississippi River levee just south of Oldtown Lake. No further work is required upon the White River backwater levee beyond some possible future moderate grade adjustments not yet in the planning stage, and its connection with the Mississippi River levee by extension along Oldtown Lake, where drainage adjustments remain to be made by local interests (but where the ground is so high that scarcely any levee is needed). The cost of completing the White River backwater levee is estimated at about $500,000.
On the east or left bank of the river the project starts at Cairo, Ill., which, with the adjacent Cairo Drainage District, occupies a peninsula between the Mississippi and Ohio Rivers which is converted into an island by Cache River which empties into the Ohio a short distance northeast and almost reaches the Mississippi a short distance northwest of the city. The city and drainage district are surrounded by a ring levee system. The Cache River is to be divorced from the Ohio by an extension of the Ohio River levee northward to Mound City, and is to be diverted into the Mississippi. The present Mississippi River levee at Cairo will be extended up the diversion channel to high ground near Mounds, Ill. Thus Cairo will be tied into ground above overflow by both the Ohio River levee and the Mississippi River levee; and the present levee along Cache River will become obsolete. The Cache diversion, which has been assigned to the Ohio River division, involves bridge construction and so could not be undertaken during the war. The Mississippi River front levee up to the Cache River levee has been brought to grade. The Ohio River front protection has not been completed except for 1.4 miles of set-back levee near the mouth of Cache River,
Right-of-way difficulties have interfered with the enlargement of about 1.3 miles of levee and of the 2.5 miles of flood wall which now protects the Ohio River front. Of the latter, about .85 mile has been offered to contractors, and another .85 mile will be offered soon for construction with fiscal year 1946 funds. For the remainder of the front now protected by flood wall the city plans to provide right-of-way for a levee in lieu of the present wall. The deficiency act of last December provided $1,000,000 for completing the flood wall. An addi
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tional sum of about $1,000,000 will be needed to construct the levee which will replace the existing wall below Fourteenth Street.
The east bank of the river is unleveed between Cairo and Hickman, Ky., which is the head of the Reelfoot levee district. The Reelfoot levee extends from the Hickman Bluff a distance of 22.7 miles downstream to Slough Landing Neck where it ties into high land. A dike extends out along the Neck and is being raised for a length of 3 miles in order to prevent a cut-off. The city of Hickman is protected by a levee and flood wall which is to be raised about 6 feet at a cost of $600,000. The Reelfoot district levee is all up to grade except for 3.5 3.5 miles opposite chute of island 8 now under construction to project grade and section.
The east-bank levee resumes again physically at the end of the ridge along Reelfoot Lake, near Tiptonville, Tenn., and extends downstream at a grade 3 feet below the St. Francis Basin levee opposite, a distance of about 15.7 miles. This levee was recommended by the Mississippi River Commission in House Document No. 188, Seventysecond Congress, first session. Its construction was finally authorized as a flood-control, general, undertaking by the act of June 22, 1936, so it is not technically a part of the adopted project “Flood control, Mississippi River and tributaries."
The protection of the east-bank basins against small high waters is extended downstream to and beyond Booths Point by highway fills and small private levees, beyond which, above the city of Memphis the flood plain is too narrow and too much cut up by tributaries to lend itself to protection.
Protection of Memphis to a grade of 1.7 feet above the grade of the opposite levees protecting agricultural lands in Arkansas is being provided by a series of flood walls and levees along Nonconnah Creek and Wolf River supplemented by pumping plants, for evacuation of rainfall and sanitary sewage under a flood control, general, project authorized by the act of June 22, 1936, at a cost of $9,000,000. The levee and pumping plant along Nonconnah Creek have been completed, as have 2.1 miles of levee, and one pumping plant along Wolf River The recent deficiency bill provided $950,000 for the project, and $1,000,000 more is being asked for in the forthcoming appropriation bill. With these funds it is expected to build the remaining four pumping plants, and 0.54 mile of wall and 3.75 miles of levee along Wolf River. An additional $6,500,000 will be required to complete the remaining 0.65 mile of levee and 2.6 miles of wall along Wolf River.
Beginning just south of Memphis and extending to Vicksburg, Miss., lies the Great Yazoo Basin, an area about equal in size to the States of Connecticut and Rhode Island combined. It is protected against floods of the Mississippi River by a continuous levee line 271 miles long and 29 feet in average height, extending from the bluffs below Memphis to the bank of the Old Yazoo River just above Vicksburg. The western part of Vicksburg itself is subject to overflow, and is protected by a flood wall about 4,200 feet long supplemented by short levees. The wall and levees are to be raised about 6 feet under the project at an estimated cost of some $2,000,000. Two hundred and two miles of the Yazoo Basin levee are up to grade or under contract, leaving 69 miles still to be enlarged, of which it is planned to take care of about 30 miles this coming fiscal year. On about half of the remainder, the levee crown is already up to grade but the embankment
is not faced by an impervious blanket and does not have a 25-foot-wide crown-or it is otherwise slightly deficient in cross section; for the remaining half, the levee is slightly below grade.
The levees of the Yazoo Basin have been strengthened by the addition of about 90 miles of seepage berms designed to guard against danger from sand boils.
After leaving Vicksburg, there are no levees on the east bank of the river above Baton Rouge.
Passing now to the west bank, protection of the great Tensas Basin whose area is 5,370 square miles is accomplished by a levee 378 miles long and about 26 feet in average height. In order to tie into high land, this levee has to originate at Pine Bluff on the south bank of the Arkansas River about 117 miles above its mouth. It is the longest continuous levee line on the river.
The portion which follows the south bank of the Arkansas River is 66 miles long. It is not as high as the Mississippi River portion of the line but will average about 20 feet in height when completed. About 28 miles are already completed or under contract to present approved grade; of the remaining 38 miles, which require grade increases of from 1 to 6 feet, some 26 miles embracing the lowest stretches are to be cared for this coming fiscal year, leaving 12 miles for future years. About 8 miles of seepage berms have been built or are under contract.
The arbitrary dividing line between the Arkansas River levee and the Mississippi River levee is at Yancopin. Between that point and the lower end of the levee near Old River at Point Breeze-312 leveemiles—the embankement will average 28 feet in height. About 172 miles have been brought to grade or are under construction to grade. This includes 15 miles at the extreme lower end which are to remain at 1914 grade. Some 60 miles—between Willow Point and Lakeportshown on the chart as needing treatment are already above grade, but are to be given an impervious facing at some future time. Of the remaining 79 miles which require raising, 35 miles are to be raised during the coming fiscal year and the remainder in subsequent years. About 17 miles of seepage berms have been completed or are under construction. In general, the west-bank soils are less permeable than those of the east bank.
In the general vicinity of Old River, the project flood flow of 3,000,000 cubic feet per second is to divide equally between the Mississippi and the Atchafalaya Basin. The east bank of the Mississippi is not leveed between Vicksburg and Baton Rouge because the overflow basins are too narrow to warrant the cost of the high embankments that would be required for their protection. The highlands end at Baton Rouge, however, and the Pontchartrain and Lake Borgine Basins aggregating some 2,000 square miles require protection. The levee begins at Baton Rouge and is continuous for 172 miles to Pointea-la-Hache. Its average height is about 161/2 feet. At Bonnet Carre, some 33 river-miles above New Orleans, it is interrupted by the Bonnet Carre spillway, a needle dam structure some 7,700 feet in length whose function is to pass enough water from the river via a leveed floodway into Lake Pontchartrain to prevent the Carrollton (New Orleans) gage from reading higher than 20 feet. With 1,500,000 cubic feet per second in the river below Morganza, the withdrawal necessary to peg the Carrollton gage at 20 feet is estimated at 250,000 cubic feet per
second. The spillway has operated twice—1937 and 1945—and has performed its necessary function adequately both times.
On the west bank of the river, the levee is continuous from the head of the Atchafalaya River to the Jump (271 miles). Its height averages 161/2 feet. Both the east bank and the west bank levees below Old River are in general at or above approved grade. The exceptions are relatively short, isolated stretches, which are slightly deficient in grade or cross section or both. These deficiencies are being corrected as maintenance set-backs are made. The tightness of the soils below Old River makes the need for seepage berms infrequent. There are, however, about 112 miles of them.
As noted above, the east bank levee, insofar as the adopted project is concerned, ends at the Pointe-a-la-Hache gap. The levee line originally extended as far toward the Gulf as the west bank levee, and was included in the programs of the Mississippi River Commission to its end. In 1926, however, local interests, with the consent, but not at the instigation, of the commission created a relief outlet for floodwaters by degrading about 11 miles of levee southward from Bohemia, La. No further work was performed by the commission on the 22 miles of levee south of the outlet and it was not specifically mentioned in the project adopted in 1928. The territory behind it has, however, now developed into a great oyster and fur producing area with some cattle industry. The bank for some distance inland along the degraded reach has built up a great deal from repeated overflows, and diversions from the river are now largely concentrated in a few breaches in these natural levees. The land behind the levee southward of the gap has not built up and a crevasse in the levee would permit damaging flows to invade the area. During the flood of last winter assistance in preventing crevasses was rendered under section 6 of the 1928 Flood Control Act and there is small doubt that requests for aid will continue. The estimated expense involved is $400,000 to $600,000 required in the main for wave-wash protection.
The 1,500,000 cubic feet per second of the project flood flow which is to be carried through the Atchafalaya Basin has three distinct routes of travel down to the end of the Atchafalaya River levees where all three merge into a single broad leveed floodway about 15 miles wide with two outlets—one, the natural channel of Berwick Bay at Morgan City, the other, an artificial dredged and leveed channel near Calument, La., called the Wax Lake outlet. The separate routes followed in the upper part of the floodway are the Atchafalaya River, which is leveed for 55 miles below its head, which carried the flow of Red River plus flows of varying amounts from the Mississippi at practically all stages, and which, in the project flood, will probably carry from 600,000 to 700,000 cubic feet per second; the Morganza floodway, about 5 miles wide, which leaves the Mississippi just north of Morganza, La., and in a project flood will probably carry 600,000 to 650,000 cubic feet per second; and the west Atchafalaya floodway, some 10 miles wide which will come into action last and will carry the difference between the combined capacities of the Atchafalaya River and the Morganza floodway, and the 1,500,000 cubic feet per second required to be diverted. If the Atchafalaya River and Morganza floodway perform as planned this difference will be but 150,000 to 300,000 cubic feet per second. The capacity of the west floodway is estimated