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eddy pocket that had formed just at the foot of the 1894 work. The subaqueous mat was sunk during a rising river and at the 19foot stage, and, consequently, laps over 50 feet on the bank from the zero stage. The upper bank was graded by the hydraulic process, but owing to its composition it washed so badly that but one stream could be used and much shovel work was necessary to produce a proper grade for the paving; 4,000 square yards of paving of the previous character was placed along the new work, with its upper edge at the 33-foot stage, and 535 square yards of old paving, which was somewhat displaced by settling, was repaired. The total field cost of the season's work was $13,000.
SEASON OF 1898
During the high water of this spring there was some caving just above the head of the work and also some slight caving below its lower end, but the revetment itself was unharmed. During this season the revetment was extended upstream to prevent further caving there. A fascine mat, 355 feet long by 265 feet wide, was placed at the head of the work and across a depression known as Dry Slough. Another mat, 1,218 feet long by 265 feet wide, extended the revetment downstream. Two connecting mats were placed along the latter, and the bank paved to the 33-foot stage. In this paving the bank was first covered with a 4-inch layer of spalls and on this was placed the riprap, 8 inches thick at the bottom of the slope and tapering to 6 inches thick at the top. The amount of mat constructed was 4,375 squares, and there was this year added to the revetment 1,533 linear feet, making the total revetment in place 3,643 linear feet.
SEASON OF 1899
An examination of the work made after the spring rise showed a settlement of the shore edge of mat where it crossed Dry Slough, caused by the discharge from this slough cutting under the mat. There had also been increased scour of the bank above the top of the paving along the business portion of the town, where the work of 1893 had been carried to the 27-foot stage only. This scour had been going on for some years during high-water stages, but had now become so great that there was danger of the water cutting down and behind the paving. The bank immediately below the revetment had scoured but little since last season, but about 1,800 feet below a gully of considerable size had been caused by the storm water from Cypress Slough falling over the bank.
The work of this season comprised repairs at the localities above noted and the extension of the revetment downstream. A fascine foot mat, 110 by 60 feet, was sunk across the mouth of Dry Slough, and a paving was placed along it on the bed of the slough from bank to bank. A foot mat, 100 by 40 feet, with paving along it to the top of the bank, was also placed in front of the mouth of Cy. press Slough, and the paving along the town front was extended to the top of the bank for a length of 500 feet. The revetment was extended downstream 800 feet, with a subaqueous fascine mat 275 feet wide, the paving along which was carried up to the 25-foot stage, the bank being graded by hand, as the natural slope was practically 1 on 3.
All of the work placed at New Madrid has been quite effective in protecting the bank from caving; it is now in good condition and no further extension is contemplated, as the bank for some distance below it has practically ceased to cave. The total length of the revetted bank is 4,500 feet and the total cost has been $151,000.
CARUTHERSVILLE, MISSOURI (One hundred and ten miles below Cairo, right bank.) The bank in front of this place began to cave rapidly in 1897, and Congress being appealed to made in 1898 a special allotment of $20,000 for its protection. This sum being insufficient for the construction of a continuous revetment along the entire city front, it was decided to construct a series of four brush and stone spur dikes. (Plate XLIII.) These dikes were to be spaced 450 feet apart, center to center, and were to consist of the usual form of brush and stone cribs resting on fascine sill mattresses, each sill mattress to be 120 feet long and to extend out about 200 feet from the low-water line; the upper bank along these sill mattresses was to have the usual bank paving. Each dike was to be built of two cribs, the bottom one being 150 feet long by 20 feet wide and 8 feet high, and the upper one was to be 10 feet wide, 8 feet high, and of such length that it would extend from the top of the graded bank to near the outer edge of the sill mat.
SEASON OF 1898
It was expected that the entire project would be completed this season, but owing to some delays in the papers relating to the
project it was not until late in November that the approval of the Impartment was received and the work could be started.
Work was begun November 28, with the river at a most unfavorstile stage and still rising and much drift running. This delay in beginning operations was very unfortunate, for it prevented the completion of the project. Three of the sill mats were completed without any difficulties, but while the fourth was under construction ice began running, and this compelled a temporary stoppage of work and the retirement of the plant to a place of safety, in order to prevent damage to it. At this time 85 feet of mat was afloat; this was launched off the ways and swung into the bank and prowrited against the ice floe. After four days the ice ceased running and the mat plant was brought back into position, the mat hauled wut to its proper place and completed to its required length by securely sewing to it the 35 feet still needed, after which it was sunk. Grading began as soon as the first mat was down, which, in order to avoid interference from the grader, was a downstream one. Crib No. 1 was begun under very unfavorable conditions of river, and in attempting to lower it to the bottom the pressure of the current and drift against the 8-foot wall of the crib became too great for the mooring lines to resist. Three of these, two 1-inch steel cables and ode 24-inch manila line, parted, while a fourth steel cable pulled out its shore anchorage. This set the whole outfit adrift, and the erib was hurriedly let go, going down to the bottom all right, but somewhat out of place. The reports from the upper rivers being then very unfavorable, and it being so late in the season (January 21), no further work was attempted here, except the completion of the paving at the site of each of the four spurs. The mats as constructed were 220 feet wide, reaching out about 200 feet from the zero contour.
The project, as described above, was probably the best that could be devised for the expenditure of the small amount of funds allotted, and if completed it might have held the bank for some time. The banks here are very high, and the water in front, 200 feet from shore, ranges from 43 to 59 feet in depth below mean low water, with a moderately strong current at all stages. These conditions are suitable to the creation of strong eddies between the spurs, and these once created rapid erosion of the unprotected intervals would have taken place, which would probably eventually have destroyed the spurs themselves, or else cut them away from the bank. How
During the high waitr vf this vason the work as plaed proirini tie bank to a wasidcrabit estrot against further caring ang the murder, there having been but little caring between tkt varius lais up to the tice vreining work the following var. But know the size crib a very large [uwket had been escarat by the streg tudy ertaini by this erib. Plate XLIT. This edds paket. and Sole others that had formed below the town, showed eirar.y that the bank was subjet to rapid destruction if attacked in this way and that the locality was not one where spurs could be used to advantage.
There became available this season a new appropriation of $3.5.1**), and the promit for the expenditure of this sum called for the abandonment of the old project and the substitution for it of continuous work, using as far as possible the sill mats already in place and removing the old and damaged crib above low water.
Active operations were begun September 1. Three subaqueous mats, 2013 fert wide, were constructed in the intervals between the four sill mattresses placed the preceding season, each new mat lap. ping at the head and foot over the old ones. Below the fourth of the sill mattresses a new mat was constructed, continuing the work downstream about 100 feet. Along this entire length the bank was graded to the usual slope of 1 on 3. except at the salient left at the site of the lowest spur by the eddy earing. Here the grade was made Hatter and the point rounded off somewhat to diminish the strength of the eddy.
The bank was then pared, and according to the project this should have been extended to near the top of the bank, but the shortage of the stone supply prevented this, and as a result at the end of the season the paring reached only to the 18-foot stage, except at and near the point where it extended to the top of the bank, it being expected that the point, on account of its saliency, would be subjected to stronger attack at high water.
The revetment as thus constructed is continuous for 1,890 feet of bank and has effectively stopped the caving.
Since 1899 there have been no funds available for further work, and no damage has been done to the existing revetment except at two or three places, where concentrated surface drainage has
caused some settlement of the bank paving. This matter has been called to the attention of the city authorities and they have promised to prevent further damage from this cause. However, below the town caving has gone unchecked, and there have been shown here some good examples of eddy caving that have been previously described. (See page 19.) It is probable that if this caving is pot checked it will eventually work up back of the existing revetment and destroy it. Consequently, it is expected that in the near future funds will be made available for use at Caruthersville, to be espended in extending the paving to the top of the bank and in continuing the revetment downstream.
The total cost of this revetment at Caruthersville has been $55,000
Plum Point Reach.-(From 150 to 170 miles below Cairo.) The banks along this reach have been revetted at several localities : Daniels Point. (From 150 to 152 miles below Cairo, right bank.) Ashport Bend. (From 153 to 156 miles below Cairo, left bank.) Fletchers Bend. (From 158 to 161 miles below Cairo, right
Plum Point. (One hundred and sixty-four miles below Cairo,
Daniels Point.--As has been previously stated, the revetment work at this locality was begun in 1889, when 5,300 feet of bank were revetted with what was at that time the standard type for such work. Faults began to develop in the work at the next high water and became greater as time went on. Repairs were made in 1891 and 1892, but these failed to stop the destruction of the work.
SEASON OF 1895
(Plate XLV.) No further work was done here until this season, and when operations were renewed it was found that of the 5,300 feet put in only about 900 feet now remained in good condition, one piece 500 feet long near the lower end and another 400 feet long some distance below the head of the work. Above this several hundred feet of work had been completely destroyed by the river cutting in behind it. Soundings along the other damaged parts of the work seemed to show that the river mats were still in existence,