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section of river quickly attained impressive dimensions. The river established increases in its velocity records and increases in its discharge quantities as compared with those elements corresponding to similar previous stages.
From Natchez to just above Angola, in which 60-mile stretch of river there was only one cut-off--and that was notably not a very efficient cut-off--new high-water elevations were established that exceeded those of 1927. It is probable that the 1937 flood heights may have exceeded those of 1927 much farther downstream than Angola, were it not for the fact that the Mississippi River was at unusually low stages for many weeks preceding the beginning of this flood wave. The Atchafalaya River was likewise at a low stage and the reservoir relief offered by the backwater area in the lower end of the Fifth Louisiana Levee District was available to a greater degree than is usually the case, by reason of these low river stages. Then there was the Bonnet Carre spillway, the operation of which materially helped in keeping the river stage down. With all these favorable factors operating for the benefit of the lower river the stages nevertheless were high, being 2.0 feet below 1927 at Angola, 2.8 feet below 1927 at Baton Rouge, and 1.9 feet lower than 1927 at New Orleans.
An inspection of the hydrographs of the 1929 and 1937 floods does now show 1937 to be a flood as great in volume as that of 1929.
At Cairo the period that the river exceeded the flood stage of 40 feet was 51 days in 1937, as compared with 93 days in 1929.
At Memphis the period that the river exceeded the flood stage of 34 feet was 43 days in 1937, as against 92 days in 1929.
At Angola, the river was above the flood stage of 45 feet for 50 days in 1937, as against 96 days in 1929.
At New Orleans the river exceeded the flood stage of 17 feet, 40 days in 1937 as against 85 days in 1929.
Conservative river observers have expressed the opinion that under normal and previously existing river conditions, a flood of the 1937 character and magnitude and under similar preflood river conditions could easily have been passed at New Orleans, at 19 feet on the gage, and without operating the Bonnet Carre spillway. But due to the speeding up of the discharge caused by the cut-offs in the upper reaches of the river, or to express it in another way, due to the delivery to the lower river of more cubic feet per second than is normally received, the flood reached a stage of 19.1 feet even with the Bonnet Carre spillway operating. Until this situation is corrected, the flood-reducing effect of the Bonnet Carre spillway is nullified.
This is readily understood when it is explained that previous to the up-river cut-offs, there was an average slope of approximately threetenths of a foot per mile in the high water flow line between Arkansas City and Angola and approximately two-tenths of a foot average slope per mile between Angola and Carrollton. The shortening of the river length by the cut-offs, even though some of these are as yet not fully developed, has resulted in an average slope per mile from Arkansas City to Angola of four-tenths of a foot, or twice the amount of slope existing below Angola. Steeper slope means greater veolocity and greater velocity with the same cross section means greater discharge. The record shows that with 55.1 feet on the Vicksburg gage,
the discharge in 1937 was 300,000 cubic feet per second more than in 1929 at the same gage reading, so that it is seen that the river is behaving true to form.
It is respectfully submitted, that in view of the accelerated discharge of the floodwaters of the upper river into the reaches of the lower river, where no changes have been made or can be made toward increasing discharge capacity except by adding to flood heights, the remedial works planned to take care of this condition through the construction of the Morganza floodway be considered in the light of emergency work and that Congress be urged to pass the necessary amendment with the least delay to permit their speedy execution.
Senator OVERTON. Now, Mr. Klorer, in view of the fact that you are an engineer for the Sewerage and Water Board of New Orleans, I want to ask you whether or not the city of New Orleans is considering the construction of Morganza floodway and whether it has been considered that the operation of the floodway would be to the advantage and protection of that great city.
Mr. KLORER. That is unquestionably the opinion of the interested parties in the city of New Orleans.
Senator OVERTON. I infer from your statement that you entertain the view that instead of a necessity for the Morganza having decreased during the last few years, the necessity for the construction and operation of the Morganza floodway has increased?
Mr. KLORER. Yes.
Are there any other questions? If not, we thank you very much, Mr. Klorer.
We will next hear from Mr. Jacobs.
STATEMENT OF HARRY JACOBS, CHIEF STATE ENGINEER OF
Senator OVERTON. Will you give your name, residence, and official position to the reporter?
Mr. Jacobs. Harry Jacobs, chief State engineer of Louisiana.
Senator OVERTON. Mr. Jacobs, how long have you been engaged in the engineering profession approximately?
Mr. Jacobs. About 28 years. I have been on the river about 25 years. I have been connected with the board of State engineers for 23 years and have served as chief State engineer, with the exception of a short time of about a year, since 1928.
Senator OVERTON. As chief State engineer, what is your main work? Is it in relation to flood control on the lower Mississippi Valley or is it something else?
Mr. JACOBS. No; among other things, it is principally flood control in the lower Mississippi Valley.
Senator OVERTON. The Mississippi and its tributaries?
Senator OVERTON. Are you familiar with the bill that we have under consideration?
Mr. JACOBS. Yes, sir.
Senator OVERTON. I should like you to give the committee the benefit of your views in reference to that bill.
Mr. JACOBS. Mr. Chairman, and members of the committee, it has been just about 11 years since the great flood of 1927. Following that flood the Congress authorized the 1928 Flood Control Act. That act provided for the enlargement and raising of the levee system on the Mississippi River, the Bird's Point-New Madrid floodway, the Boeuf floodway, the Atchafalaya floodway, the Bonnet Carre spillway, above New Orleans.
Work was first started in the upper stretches of the river in each of the different basins, and it was the intent, as the act provided, to correct flood conditions on the main stem of the Mississippi River. The act provided that this should be extended into the tributary areas as far as the effect of waters on the Mississippi went. The levee system on the Mississippi River has been rebuilt and I would say completed with the exception of necessary changes that occur from time to time to be made. Bird's Point-New Madrid floodway has been completed. The Atchafalaya floodway has been practically completed.
Senator OVERTON. That is, the West Atchafalaya and the East Atchafalaya?
Mr. Jacobs. The Atchafalaya floodway, with the exception of the upper part on the east side, in the Pointe Coupee Parish.
The Bonnet Carre spillway has been completed.
Each of those projects was undertaken separately and completed. It was a necessity that they be completed, because of the dependence on them for protection of lives and property in the most thickly populated areas of the valley.
The city of Cairo has been given full protection, Greenville has been protected, and in addition to the work provided for in the original act, there has been an additional 4 or 5 million dollars spent there by the construction of a dike in the river since the cut-offs have been made, and in doing all of this work there has not been one dime spent in the city of New Orleans. The city of New Orleans has protected itself.
The Bonnet Carre spillway was constructed some 30 miles above the city at a cost of thirteen and a quarter million dollars, but I do not believe today that, after all of these works have been completed, the area on the Mississippi River above the city of New Orleans, which is the area that supplies the city and makes it possible to a large extent for the city to exist, has complete protection. I do not believe any area on the river that has only 1 foot freeboard is completely protected.
In the original 1928 act there were 35 miles of fuse plug provided for at the head of the Boeuf and Tensas Basins. There has existed from that time down to the present in the construction of these levees a fuse plug of 60 miles. There was also provided a fuse plug at the head of the Atchafalaya Basin of about 40 miles. That fuse plug length of section of the levees remains there today.
Following the work authorized under the 1928 act, after many controversies about the engineering works provided for in the act and after the hydraulic laboratory had been established at Vicksburg and ample time for additional studies of the river was provided for, it was then agreed by all those concerned in the valley that the 1928 act should be amended. That act was amended in 1936 by an amendment introduced by yourself.
In the original report of the Mississippi River Commission called for by the House Flood Control Committee in 1935, it was recommended that in lieu of the East Atchfalaya floodway, the Morganza floodway be constructed, and in lieu of the Boeuf Basin floodway (which was conceded by all not to be the final or the proper location for the floodway) the Eudora floodway be constructed.
Several years before this amendment was passed, under authority of Congress the Government Engineers had done a great deal of channel correction work in the Mississippi and the Atchafalaya. Today there have been constructed 13 cut-offs in the Mississippi River, and it has shortened the river by 113 miles. The Atchafalaya River has been enlarged by channel corrections, such as various kinds of dredging to develop and increase the outflow of that river.
Any plan of engineering proposed 10 years ago or 20 years ago necessarily will change as times change and the conditions of the regimen of the river change.
Senator OVERTON. In that connection, the President of the United States, in a message to Congress the other day, said that our floodcontrol plan should
be revised annually. Here is his statement: (Reading :)
Our knowledge of the Nation's water resources and our ideas on their best use and control change rapidly in the light of new investigations and of dynamic economic conditions. Water plans should be flexible. The history of floodcontrol plans for the alluvial valley of the Mississippi River affords many examples of plans once considered comprehensive, which soon were replaced by others. Water plans should be revised annually.
I mention that because it is in line with your statement.
Colonel Potter, who was president of the Mississippi River Commission in 1928, in his comprehensive plan refused to recommend it as a final plan at that time, because he, knowing the river for the many years that he had been on it, recommended an interim plan which would permit studies to be made because of the changing conditions of the river. That has been referred to by nearly every engineer in the Government who has made any plans on the river.
Before you introduced the amendment in 1936, these cut-offs had been under way, and when the flood of 1936 came out of the Mississippi Valley, which I considered to be the superflood of the Ohio Valley, and when it arrived at Arkansas City it passed there with the lower gage reading of 10.5 feet in the same volume that it passed during the 1927 flood. When that same flood arrived below Natchez or in the Natchez area, it was 2 feet above the 1927 flood.
Now, there have been certain works done in the Atchafalaya River, but because of these cut-offs and the changing of the river and the shortening of that stream, the river had picked up tons of silt which it could not pass through into the Atchafalaya River; consequently a great deal of it went down into the lower Mississippi River, below Angola. Conditions in the lower river south of Angola have also changed.
The cut-offs today are not operating 100 percent. There is only 1 out of the 13 that is, and that is the one at Leland. The others vary from 25 to 65 percent.
The cut-offs today are not operating 100 percent. There is only 1 out of the 13 that is, and that is the one at Leland. The others vary from 25 to 65 percent.
It is my opinion, from the information that I have been able to gather through contact principally with those in authority for the Government, that when these cut-offs are developed fully and carry the full load, we can look for a greater carrying of volume than was carried during this past flood.
General Ferguson is in a much better position, through the assistance of those engineers who are under him, who make the various observations, to determine, from actual observation, volumes and the effects of the river as it is today as compared to that of the river existing during 1929. Nineteen hundred and twenty-nine was the first highwater of any consequence that passed through the levee system without a crevasse, and it is, of course, our belief that it is of vital importance to south Louisiana to immediately construct the Morganza floodway to prevent an overflow or topping of the 40 miles of fuse plug levees at the head of the Atchafalaya Basin in the next major flood.
Morganza should be constructed because it will add the additional factor of safety to the lower Mississippi Valley in the State of Louisiana north of the city of New Orleans and north of the Bonnet Carre Spillway.
The last time any floodwaters from the Mississippi River entered the city of New Orleans was in 1849, and while we have had floods greater than that of 1927 at the city of New Orleans, I do not believe that it is possible, under the present condition, for the city of New Orleans to be overflowed. I think the city of New Orleans is perfectly protected as a city, but the surrounding territory, especially that north of the city, which is the territory upon which the city exists, is not protected unless the Morganza is constructed.
Prior to the Overton amendment in 1936 as originally drawn, a great many of those present in this room today were present in a room in the Peabody Hotel in Memphis when we agreed upon the engineering changes that were to be brought here to Washington and laid before you, when we requested you to introduce that amendment. There were representatives from the State of Mississippi, and there were representatives from the State of Arkansas, and in that room in the Peabody Hotel, together with the representatives from Louisiana, they all entered into a gentleman's agreement that that was what we would request to be done.
Prior to your amendment there was no payment for any lands in any floodways. There was no payment or any provision made for intercepted drainage. There was no provision made for bridges or roads along these levees. Those things were included in your amendment.
It was agreed upon at that time that the proper elevation of the weir at the head of the Eudora Basin should be constructed in order to skim off the crest of the flood and prevent disasters during superfloods in that stretch of the river south of Arkansas City. The same provision was agreed upon to be put into that amendment which applied to the Morganza floodway. The elevations arrived at and which were written into that act were the result of a lot of deliberation and consideration by those informed and in authority in the State of Mississippi and also in the State of Arkansas, as well as Louisiana.
Conditions have changed so that we find today, and I believe it will be conceded, and I believe you have been told by the Government engineers, that it is no longer necessary for any such floodway as 10 miles wide through north Louisiana, but because of those same changed