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worst parts of the channel, and to greatly increase the depth for several miles down the chute.
At the foot of Half-moon Island a dam and some excavation in channel will be required, which will probably cost $3,000.
Shields's Dam.-Nothing has been done here.
Turner's Bar. A small amount of rock-excavation in channel has been done here, leaving about four-fifths of it yet to be completed.
Caney Creek Shoals.-The improvements originally ordered at this point have been completed; but, although we have gained 12 inches in depth, we have not yet secured 3 feet depth, as desired, there not being more than 28 inches in the channel at low water. Another dam will have to be constructed at the foot of these shoals in order to give the desired depth. The probable cost of this dam is $5,000.
Long Island Shoals.-The rock for the dams has been quarried, and the work is about half finished.
Seven Island Shoals.-All the stone required for the dams at this point has been quarried, leaving about two-thirds of the work yet to be done.
Wilson's Island Shoals. All the stone needed in the dams is quarried, leaving about two-thirds of the whole work yet to be done.
Bacon's Shoals.-Nothing has been done here.
Bogart's Shoals.-A dam 575 feet long has been built, and half the channel.excavation bas been finished.
Sweetwater Shoals.-About 1,000 linear feet of dams have been built, and 500 are set to be built. An increase in channel-depth of 9 inches has been gained.
Harrison Shoals and London Shoals.- Nothing has been done here.
The character of the work done is well indicated by the fact that, although during the past winter these dams, with a united length of three iniles, have been subjected to the almost continuous action of heavy freshets, loaded with trunks of trees and other heavy floating objects, the damage which they have sustained is so slight that not more than 200 cubic yards of stone would be required to repair them.
Until the interstices between the stones of which they are composed are filled by the drift, the whole effect of these works cannot be ascertained. This tightening of the dams will also strengthen them; and Mr. Hampton, the very able assistant engineer, who has supervised the work on the Upper Tennessee, proposes to further strengthen them by planting willow-twigs upon them. This was tried last year at Sanda Shoals, Half-moon Shoals, and Caney Creek Shoals; and about onethird of the twigs are still alive and flourishing, which is quite a fair result.
The chief difficulty that has been experienced in conducting this work arises from the sudden changes occurring in the stages of water in the river. A slight rise is commonly sufficient to put an end to channel-excavation, and work upon the dams is often stopped in the same way. Where the rise seems likely to last for a time, it is often necessary to disband the working-parties, as their subsistence, while idle, would increase too much the cost of the work, and some delay is of course experienced in re-organizing them again.
Some injury has been done to the dams by thoughtless people in making passages through tbem for their canoes. These gaps are apt to increase in size and to diminish the effect intended to be produced by the dams. There is probably no remedy for this, except united action on the part of steamboat-men and others who are engaged in the navigation of the river, and who from their occupation are better able
than any one else to ascertain who are the mischief-doers, and to make known to those who live along the river the danger to navigation of such injuries.
The estimates heretofore given for the improvement of the Tennessee River between Chattanooga and Knoxville are to be found in the reports of Capt. L. C. Overman, Corps of Engineers, dated August 9, 1871, and January 5, 1872, contained in the Annual Reports of the Chief of Engineers for the years 1871 and 1872, at pages 502 and 438 respectirely.
It will be observed that these estimates are based upon rapid examinations of the river, the first, between Chattanooga and Kingston ; the second, between Kingston and Knoxville; and were intended to be but approximations. The more careful examination of the river by a party specially organized for the purpose, which has been begun under the recommendation of the Senate Select Committee on TransportationRoutes to the Seaboard, will give us the means of correcting those estimates, and in the meanwhile, as a convenience for future reference, I will give bere an abstract of Captain Overman's estimates.
In the first estimates, for points lying between Chattanooga and Kingston, the quantities only of work to be done are given, and no prices. I have, however, given the prices for which the work could hare been done under the lowest bids received for a part of the work as advertised, as given in the Report of the Chief of Engineers for 1872, page 484. In this estimate, nothing was allowed for contingencies or supervision of work.
In the second estimate, for points lying between Kingston and Knoxville, I have added the 60 per cent. mentioned as the increased cost of a three-foot channel over a channel but 24 feet deep.
The points mentioned are taken in order, beginning with that one wbich lies nearest to Chattanooga.
Chattanooga to Kingston : Sanda Shoals.
$6, 100 00 Kelly's Shoals.
4, 425 00 Watts's Bar.
1, 087 50 White's Creek Shoals..
6, 475 00 Half-moon Shoals.
8,450 00 Shields's Dam...
4, 562 50 King's Shoals..
5, 606 25 Turner's Bar...
2,725. 00 Caney Creek Shoals.
$17, 156 25 Kingston to London: Long Island Shoals.
4,000 00 Seven Islands Shoals.
5, 120 00 Wilson's Island Shoals.
3,680 00 Bacon's Shoals...
1,934 00 Bogart's Shoals.
5, 280 00 Sweetwater Shoals
8,000 00 Harrison's Shoals.
1,280 00 London Shoals...
1, 280 00
30, 624 00 London to Knoxville : Bonder's Sboals...
2, 560 00 Lenoir's Shoals..
6, 080 00 Bell Canton's Shoals.
960 00 Bustle's Bar.....
2, 560 00 Sister Island Shoals.
2,400 00 Coulter's Island Shoals.
5, 120 00 Chota Island Shoals...
10, 210 00 Russell's Shoals..
9, 920 00
Little River Shoals..
$9, 200 00
61, 280 00
Superintendence, contingencies, &c., (making the sum of these
last two estimates $125,000, as in the original report) .....
172, 156 25 Which is the original estimated cost of the improvement of the Tennessee River between Chattanooga and Knoxville, exclusive of a part of the contingent expenses. In my reports I have usually assumed the cost of in proving this part of the river at..
$175, 000 00 There have been appropriated already for this part of the river the following sums: From the appropriation of $80,000 for the improvement of the
Tennessee River below Chattanooga, act of July 11, 1870, modified by the second section of ihe river and barbor bill approved March 3, 1871..
$35, 000 00 Act of June 10, 1872...
25, 000 00 Act of March 3, 1873.
25, 000 00 Act of June 23, 1874.
25, 000 00
110,000 00 Yet to be appropriated...
65, 000 00
$110, 000 00
Froin the sum of these appropriations, namely
$40, 472 40
85, 861 43
24, 138 57 This balance will be entirely exhausted before the close of the present calendar year.
It should be remembered that the estimates for the cost of improving this part of the river were based upon examinations or reconnoissances only, and it is quite possible, therefore, that the more minute examination or survey now being made may develop the necessity for more work than was contemplated when these estimates were made.
This necessity has already shown itself at the following points where we have been working, and where additional dams are needed : Sanda Shoals, additional dam...
$6,000 00 Watts's Bar..
5,000.00 White's Creek Sboals
2, 500 00 Caney Creek Shoals ,
6, 000 00 Total....
19, 500 00 I have not thought it necessary at present to add this and the contingent expenses, omitted in the first estimate, to the $175,000 first taken as the estimated cost of this improvement, because the whole of that sum has not yet been appropriated ; and until it has been, and there is actual need for more besides, it will be sufficient to indicate simply the possible necessity for going beyond the amount first called for.
TENNESSEE RIVER BELOW CHATTANOOGA. For the reason given in my last annual report, namely, the greater necessity for the speedy completion of the works above Chattanooga,
not so much time has been given to the works immediately below Chattanooga, which are under the supervision of the same civil assistant.
Ross's Towhead.-About 700 linear feet of dam have been built at the head of the island, and about a thousand more cubic yards of rock remain to be put in it. The rock for the dam at the foot of the shoal has been quarried, although the dam itself has not been begun. The work here is difficult of construction, by reason of the strength of the current; and the scour of the bottom is so great that far more stone is needed for the dams than was at first supposed necessary. Mr. Hampton reports it as one of the hardest places he has had to manage
The quarries first opened for this work, and which were quite near it, gare out before a sufficient quantity of stone had been obtained, and it became necessary to open another one about three-quarters of a mile farther up the river.
Tumbling Shoals.—About 350 cubic yards of rock have been removed from the channel, and perhaps half as much more is yet to be removed. The current here is very swift, and is likely always to give trouble, even if all the channel.obstructions are removed. It will be necessary to place here a good capstan and ring-bolts to enable steamers and flat-boats to warp up against the stream.
The Suck; the Pot.-Nothing bas been done at either of these obstructions during the year, and but little remains to be done under the original schemes for their improvement, except the removal of the débris left by the contractor, and the completion of a small amount of work left unfinished by him.
Muscie Shoals. For the reason given in my last annual report, namely, the utter inadequad of the appropriation, no work of construction bas been attempted here. The appropriation of June 2:3, 1874, of $100,000 for the improvement of the Tennessee River below Chattanooga, includ. ing the Muscle Shoals, in addition to the balance of the appropriation for the preceding year, although not nearly suflicient to enable us to do justice to the undertaking, would have enabled us to begin work at once but for the unfortunate destruction of the records of last year's detailed surveys in the burning of our office in the early part of the year. party is now in the field engaged in the preparation of new data for the beginning of this work, and before the close of the year I expect to be able to report progress upon the repair of the old canal around Big Muscle Shoals, lying between Lamb's and Campbell's Ferries, twentyone miles and seven miles, respectively, above Florence, Ala.
I must, however, repeat the statement made in my last annual report, that it is absolutely impracticable to conduct this work either satisfac torily or economically with such relatively small appropriations. The preliminary expenses of a work of this magnitude, in the procurement of tools and the construction of works of protection, will exhaust too much of the money so far appropriated to admit of much progress in the work proper; and to omit these temporary protections would be simply to invite the destruction of any work which might be undertaken without them. This work ought not to be begun with a working fund of less than $500,000, and much more than this could be expended an. nually to the profit of the work.
The expensive system of making a large number of small annual appropriations for a work, instead of a sinaller number larger in amount, is certain in the end to make the actual cost of the work exceed its original estimated cost.
Colbert Shoals.-The work of removing rock from the channel across
Hoop-pole Reef, and of constructing the dams provided for in the original specifications, was continued to completion in the early part of the fiscal year.
In the course of operations here it was found advisable to remove more rock from the channel than had been at first intended, and to tighten, and in some cases to rebuild, the dams that had been previ. ously built under contract. Nowhere on the river is the difference between the work done by hired labor and that done under contract more conspicuous than here. While the dams built under the former system are regular, solid, and tight, those built under the latter system are crooked, loose, and weak, and must, without exception, be rebuilt. During the winter-freshets a large part of the dam built by the contractor at the head of Colbert Island has been carried away, while its extension, built under the hired-labor system, and more exposed to the shock of the waters than the other part, has stood uninjured. The whole amount of work originally ordered at this point has been done, but the effect expected from it has not been attained, because the dams first built are so loosely put together that very much of the water which they were designed to retain escapes through them. To put these dams in such order as they should have been put in originally, and to rebuild the parts which bave been carried away, will make a large addition to their original cost, which must come out of the appropriation for the improvement of the Tennessee River below Chattanooga. A force is now engaged in repairing the break in the dam, which is of such a nature and in such a position that it is dangerous for boats to attempt the passage of the channel in its present condition.
The proper construction of these dams, in the first instance, which could have been secured by the employment of hired labor, would have restuted in a saving of all it will cost now to put them in order, which will probably amount to one-half their original cost. There is no kind of construction which can so little afford to be neglected as this waterwork; but it is next to impossible to have it done as it should be done, unless the entire control of it is kept in our own bands, and the workmen are made to feel an interest in their work and to take some pride in it.
No very close examination has ever been made of the probable cost of improving this part of the river, lying between Chattanooga, Tenn., and Paducah, ky., with the exception of Muscle Shoals, the cost of a canal around which has been estimated at $1,003,000.
A hasty examination of some of the other obstructions in this part of the river was made in 1868, but it was not sufficiently in detail to admit of the formation of very reliable estimates of the cost of improving them. The detailed examination now being made of the whole river, from Knoxville, Tenn., to Paducah, Ky., with a view to its improvement, will furnish the necessary data for this purpose.
The amounts heretofore appropriated for the improvement of this part of the river are as follows, viz: Allotted from the general appropriations for rivers and harborsIn 1868
$85, 000 00 In 1869
40, 500 00 From the appropriation of $20,000, act of July 11, 1870.
45, 000 00 Act of June 10, 18.2.
50, 000 00 Act of March 3, 1873
100, 000 00 Act of June 23, 1874.
100, 000 00
420, 500 00
June 30, 1869.
$15, 239 69