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Amount that can be profitably expended in fiscal yearending June 30, 1890 $30,000, Submitted in compliance with requirements of sections 2 of river and

harbor acts of 1866 and 1867.

Expenditures apportioned as follows:

For services..

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$11,939.1

92.

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1,357.

1,520.:

451.

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Under an appropriation of $37, 500, made by the river and harbor act approved gust 5, 1886, for this harbor, I was directed to make an examination and prepar project. This examination was made in September, 1886.

The Commission, however, decided to defer any work, as the amount available w considered too small. Later, and with the understanding that the city of Greenvi would give at least an equal amount, the Commission directed me to submit a proj for protecting the bank by submerged dikes, such as had been used on the Memp front.

In obedience to their orders I prepared a project which was adopted by them July 2, 1887, and was subsequently approved by the Secretary of War.

The city, by a vote of the people, issued bonds for $50,000 for the work. Of th $47,500 were sold, and the net proceeds, $42, 277.10, were deposited in the Bank Greenville subject to my draft. This, with the appropriation made by the Uni States, gave a total of $79, 777. 10 available for the work. The fleet arrived and we began on September 15, 1887; it closed, and the fleet returned to Wilson's Point, Ji uary 20, 1888, occupying a period of four months and five days.

The average number of men employed was: September, 67; October, 217; Nove ber, 284; December, 250; January, 190; and during the time the following pla Two steamers, 6 quarter-boats, 2 pile-drivers,5 mattress-boats, 27 barges, 1 machi shop, 2 yawls, 9 skiffs, and 1 grader.

During September and until the middle of October material was plentiful and lal scarce. In November and December the amount of brush furnished by the contrac fell below the requirements and prevented the employment of as large a force as co be worked to advantage, as the weather and stage of water were both favorable pushing the work.

During the latter part of December and until the close of the work, the weath was very unfavorable. The various kinds of work may be divided into: Grading bank, building and sinking subaqueous mats, crib-work and upper bank protecti Grading. Part of the grading was done by hand, a sluice-box being used to ca the material shoveled into the river; the water for this purpose was pumped out the river by a pile-driver; this being found too expensive, in view of the large amou of grading to be done, one of the hydraulic graders was used for the rest of the wor The grader was in service about a month.

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Subaqueous mattress.-The usual method of construction was employed in this work, iron rods and wire cables being used to give longitudinal strength.

Crib work.—The method adopted on the Memphis work was used on nine of the dikes. In one dike the frame of the cribs was constructed of sawed gum lumber, 3 by 4 inches, in lengths of 8 and 16 feet, fastened by one-half inch bolts at each intersection.

Upper bank revetment.—The upper 100 feet was made of two layers of brush and the lower part of one layer, in the usual manner. It was found in ballasting the slope daring the low-water stage, that the work was so expensive and the progress made so slow (the vertical line to the top of the bank being nearly 40 feet), by carrying the stone up the slope as is usually done, that, to reduce the expense, a plan was devised of utilizing a pile-driver for hoisting the stone in a large wooden box carrying about three-fourths of a cubic yard. The box was suspended to a traveler running on a wire rope 1 inches in diameter. The driver was placed on the outside of the stone barge to be unloaded, and the wire rope led from the leads of the driver to the top of the bank, passing over a trestle about 16 feet high on the top of the bank, and anchored to a fastening in the ground about 40 feet behind the trestle. The whole apparatus was shifted from place to place as the ballasting was completed.

During the progress of the work caving occurred at Ranges 10 and 11. In both places it ceased as soon as mattresses were built and sunk there. On December 29, more than a month after the dike had been finished, a cave took place immediately above Range 8, at the foot of Washington street.

The cave extended down to the dike proper, the revetment above the dike being undermined. An extra mattress was sunk in front of this cave and carried about half-way up the slope. Since then no further caving has occurred.

After this work was finished a sinaii balance remained, and I decided to build an earthen dam or levee across the foot of the chute, to prevent in a great measure the overpour at the foot of the island. This has now been built and sacked.

By referring to the map accompanying this report it will be seen that the remains of Island 83 throws the main current away from the bank at the upper part of the town. The current strikes the bank at some point near Washington street. From here south the bank caved by the direct action of the current, and between the foot of the island and this point by an eddy current. It was this that enabled me to recommend doing this work on the lower end of a caving bank. It would be safe so long as the island remained. It was then estimated that the island would last at least two years. One of these has now passed, and should no work be done to save the small piece of island the work already done will be lost. An examination of the work was made May 31. All the dikes are intact, and no caving has occurred on the protected bank. The eddy action has been almost obliterated. There are indications of considerable fill having taken place, but a survey will be necessary to determine amount. The work has now stood the severest test to which it is likely to be exposed, and may be pronounced an entire success.

The table of cost given on the map does not include the cost of towing stone paid for by the general service. Adding this makes the cost $101,011.03, or $20.20 per linear foot. For this work I would estimate, to complete 18,000 linear feet, at $20, $360,000.

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GREENVILLE REACH.

Money statement.

July 1, 1887, amount available

July 1, 1888, amount expended during fiscal year, exclusive of

outstanding liabilities

July 1, 1888, outstanding liabilities...

July 1, 1888, amount covered by existing contracts....

$37.500.00

$37, 367.05
16.55

37, 383.60

116. 40

July 1, 1888, balance available

Amount that can be profitably expended in fiscal year ending June 30, 1890 360,000.00 Submitted in compliance with requirements of sections 2 of river and harbor acts of 1866 and 1867.

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Owing to the continuous shoaling in the channel leading from the river to the lakefront of the city of Vicksburg, steamers have been shut out for a longer period each year since the cut-off of 1876.

Many plans have been suggested, and work has been done to keep this channel open throughout the year. A report including plan and estimate made by a Board of Engineer Officers in 1878 is published in the Report of the Chief of Engineers for 1878 (pages 638 to 646, Part I).

Before the organization of the Mississippi River Commission work was begun on Delta Point, opposite Vicksburg, to prevent further recession of the bank at this place. After the organization of the Commission this work was continued, and has thus far been successful. By the river and harbor act approved August 5, 1886, an appropriation was made for this harbor. Under this a survey was made and a project with plans and estimates submitted in March, 1887. This project was later adopted by the Commission and approved by the Secretary of War.

This project is as follows:

To prevent the flow of water into the lake and make a still-water basin in front of Vicksburg. Then to dredge a basin in front of the town, and a canal connecting this with the river. To carry out this project it was proposed to build a dam across the lake from the city to De Soto Island, and a dike from near the river end of the island to the canal, and thence parallel to the canal to the river. The basin to be 1,700 feet long and 300 feet wide, and the canal 75 feet wide at bottom, with the natural slope on land side and one-fifth on water side.

Under this project advertisements were issued on August 5, 1887, for dredging. Only one bid was received.

Abstract of proposals for dredging in Vicksburg Harbor, opened September 5, 1887.

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This bid, being considered reasonable, was accepted and contract made. On November 29, 1887, advertisements were issued for piles, poles, brush, braces, stringers, and stone.

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