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pil square yards. An additional erib dike. 1.0 cubie vanis in lume
, was placed across the large washout hole of 1997 and 200 ve yards of stone placed in the form of a dike on the extreme arer end of the revetment.
With the completion of this season's work the lower 3.900 feet of 2. Hopefield bank was covered with continuous fascine mats from 31 to 310 feet wide with riprap paving laid along it up to the 26aut stage.
SEASON OF 1900
we had been a gradual caving of the unrevetted bank immeditady below, producing a large pocket, which, extending upstream Mhind the revetment, destroyed some of it. When the fascine mat of 333 was carried to the Point, this was found to be 339 feet short of a INS location, and by 1899 the Point had been moved upstream
additional 175 feet; so that in the eleven years following the cupletion of the 1888 revetment the Point had receded upstream a total of 514 feet. Owing to the importance of this Point in conmling the flow of the current along the Memphis front, it was ery desirable that no further loss be sustained, and during this vagon revetment works were to be placed to hold it. They were to consist of mats along the pocket, a crib dike across it near the middie to break up the eddy action, and the necessary bank paving. The stone paving as completed in 1891 to 1893 extended to about 6+ 24 to 26 foot stages, ending against a nearly vertical bank, which for some years did not cut, but the floods of 1897 and 1898 being much higher than heretofore caused increased currents along the trunk, cutting out holes back of the paving in some places and along marly all the balance of the work cutting back the bluff bank, so as to leave a nearly horizontal bench varying in width from 10 to 30 fret, with a maximum of 50 feet in several places. These holes had been attended to, but the continued erosion of the upper bank presented a dangerous condition, which might result in extensive xour back of the paving at the next high flood stage, cutting out other large holes similar to those made and repaired in 1897. To guard against this, it was decided to extend the paving to the extreme top of the bank.
The project as above outlined was carried out. A river mat 490 feet long by 255 feet wide was placed in the pocket below llopefield Point, and in addition four connecting mats of from 75 to 125 feet in width were required here. The total mat work aggregated 1,782
:3 kut was 256 feet long, extendjest to mit besond the low-water line 22. rato 25+729e begkt. Along 9,900 linear feet of
ot; **-***7272 Tas Iidded to the top of the bank, a 1942 arengad. In addition to the above a
2-08 Depan across one of the 1897 wash1. To: Largni, and two stone embank
- On top of the bank to check
**: mas a very monlerate one, not mate-2** * T dike placed at the lower end of
T-7 Al and had broken up the mis large deposits that it was de
- war. paint a short distance below. In: 50-tadten a strong eddy, and when 1- **mat here had settled somewhat,
02:3-527-nin above for the second time. It was t:.-L. any further seitling by destroyirz tenis -- sig hy bailding a dike across the (k-1. Time ** in the iall of this year. The one at the 1o * *as and antirely above low water and was 110mtr le mariam height. The dike in the peket was
12 in which was below the zero stage. It had a hasa ni mojomi, ani a maximum height of 141, fart. Both of the dik were parni abure low water. When the dood read it was found that the head of the lower 1899 mat had heen turned over and was turtom side up for some distance from the shore. To prevent any further movement of this mat, about 100 eubie yards of stone was piaced on it. Just abreast of the head of this mat and where one of the shore dikes ended some settling had occurred. This was repaired hy adding brush work and stone. The paring was also repaired at a number of places, generally along the low-water line, about 250 cubie yands of stone being so usest.
The present condition January, 1902 of the Hopefield revetment may be briefly described as follows:
The upper 6,300 feet consists of subaqueous mats, built between 1882 and 1885, having a width of from 110 to 150 feet. Along nearly all of this length the original upper bank revetment, made of brush ballasted with stone, has disappeared, the brush having en
sau detayed and the ballast being scattered. Fortunately, along as part of the revetment there is not a strong current and no Frial caving is taking place.
The middle portion of the revetment, 4,000 feet long, was rebuilt 9191 and 1892 with mattresses of the diagonal woven type, havwidths of from 200 to 240 feet, and the upper bank was paved restone to its top. The high-water current along this portion is sing. but the work is holding well.
The lower portion of the revetment, 6,200 feet long, was conGucted with fascine mats in 1893 and 1899, these mats being from 5 to 310 feet wide. The upper bank here is paved with stone to stop. Along this portion the high-water current is quite strong, but is not damaging the revetment.
No further work is required, except to maintain the revetment in its present state of efficiency.
The cost of this work from 1893 to 1901, both years inclusive, has heen $230,000, and the total cost from the beginning of the work in 1992, $1,066,000.
Memphis. The revetment work along the Memphis front prior po 1893 has been previously described and will only be briefly men. tioned here.
Between 1878 and 1882 a revetment was constructed along the upper part of the city front, but it was all destroyed hy 1884. Between 1884 and 1887 a new revetment was put in by the United States from above Wolf River to Beal street. Below that street and protecting some 2,200 feet of bank there was constructed in 1886 a series of spur dikes, built with funds raised by subscription. Below these dikes no work was done until 1894.
The high bluffs forming the river front from Beal street south hegan caving early in the eighties, the caving there being principally along the lower part of the city, or in the vicinity of Georgia street, where the maximum loss of bank between 1882 and 1888 was nearly 200 feet. The changes in the river lessened the attack on this portion of the bank, transferring it above, or to the vicinity of Beal street, where the spur dike revetment of 1886, already des seribed, was built.
In 1890 the Kansas City Railroad Bridge Company revetta-d the hank from about 1,000 feet above their bridge to about 30 font helow it. This left an unrevetted gap of about 3,600 forint betw«uthe bridge revetment and the Citizens' dikas, which continued to care, but not rapidly, during each high water.
SEASON OF 1894 The project for the season's work was to extend the revetmentfrom the Citizens' dikes downstream to cover about one-third of the unrevetted gap, this work to consist of fascine mattresses and upper bank paving of stone. In the execution of this project one heavy fascine mat, 1,260 feet long by 300 feet wide, and 390 squares of ... connecting mats were used. The upper bank, having a comparatively flat slope, was graded by hand and paved between the zero , and 21-foot stage with 8 inches of riprap on a 4-inch spall bed, making a pavement 12 inches thick; 10,235 square yards of this were laid.
SEASON OF 1896
During this season the revetment was further extended by con- vel structing a fascine river mat, 1,212 feet long by 300 feet wide, and m paving the bank along it up to the 21-foot stage.
SEASON OF 1898
During this season the revetment was extended to connect with the Bridge Company's revetment, thus completing the project. One fascine river mat, 1,220 feet long by 300 feet wide, and one connecting mat, 208 feet long by 25 feet wide, were placed; 7,764 : square yards of bank were paved to about the 20-foot stage.
The revetment at this locality now (January, 1902) covers 3 about 14,800 linear feet of bank, extending from 1,220 feet above Wolf River to nearly 300 feet below the railroad bridge. The work al above the Citizens' dikes, 7,700 feet long, was built by the United States between 1884 and 1887. The dike revetment, 2,200 feet long, was built from funds raised by the citizens in 1886 and 1887 sia and has been frequently repaired by the United States. Below this is a fascine mat revetment, 3,600 feet long, built by the United States in 1894, 1896, and 1898, and extending from the lower end of this a distance of about 1,300 feet is the revetment built by the bridge company in 1890. All of the revetment is continuous, except along the Citizens' dikes, where there are some uncovered intervals. The upper portion, from the head nearly to Monroe street, *** a distance of about 5,700 feet, is covered with a sand bar. The present condition of the work is good, and the only place where it is probable that future work will be required is along the unrevetted intervals at the Citizens' dikes.
The cost of the work done by the United States between 1893 and
at has been $106,000, and this, with the $138,000 expended from to 1893, and the $254,000 between 1884 and 1887, makes the utal expenditure by the United States on the revetment of Memskis about $508,000.
HELENA, ARKANSAS Three hundred and six miles below Cairo, right bank.) mretment of the bank in front of Helena was begun in 1889 by
nilding a series of spur dikes. These have been previously deviribed. (See page 183.)
These dikes, although they have not been entirely finished, effecovely arrested caving for several years. The first failures of the tank were noticed after the high water of 1894, and these were long the unfinished dikes and below them; the failures were of a zinor character, consisting of longitudinal cracks in the bank, the arth between these and the river settling for a few feet. There Tere three of these slides, one along the site of Dike No. 5 and two farther downstream. They increased in extent during the next high water and further increased and were accompanied by the formation of others during the high water of 1896, at which time the loss of bank below Dike No. 4 had become so great that it threatened the destruction of the levee, which was here close to the top line of the bank. To prevent this a project was made to pret the bank from Dike No. 4 downstream. The exposed brush work of Dike No. 4 was at this time badly decayed. The shore end of the dike had settled and the bank back of it had been considerably shattered by a slide. This was to be repaired, extended farther into the bank, and paved. All the work above this dike was effective and in good condition, except that a small amount of stone was needed on the shore ends of Dikes Nos. 2 and 3.
SEASON OF 1896
(Plate LII.) The work this season consisted in making repairs to the dikes already built and extending the revetment downstream from the lower side of Dike No. 4 for a distance of about 1,500 feet, with fascine subaqueous mats, and paving the upper bank along them with stone. Three of these mats were built; two of them, 1,255 feet long by 280 feet wide, were sunk without difficulty, and one, 300 feet wide for a length of 440 feet and 280 feet wide for a length of 617 feet, was built, but only a part of it, 430 by 300 feet, was sunk, the balance being lost by breaking during the sinking operation. Five connecting mats of various widths were constructed