I 6. IMPROVEMENT OF BLACK WARRIOR AND TOMBIGBEE RIVERS, ALABAMA. Under an appropriation of $25,000 made by act of Congress approved March 3, 1875, and in accordance with the project submitted by me for the prosecution of this improvement of these rivers, and approved by the Chief of Engineers, the work was commenced during July, 1875. On account of the difficulty encountered in obtaining necessary materials, the construction of the boats required for the prosecution of the work was considerably delayed. A small force was, however, employed at Tuscaloosa Landing blasting and removing rocks and constructing dams for the removal of some sand-bars above and below the landing. In the middle of August the first flat-boat and tender were completed, and work at Eagle Bar, below Tuscaloosa, was commenced. Three more flat-boats, with tenders, were built successively, and put on the work as fast as they could be equipped and manned, and by October 4 a full force of 100 men were employed. Three of these boats, with their tenders, were engaged on the bars and shoals in constructing the works required for their improvement, while the fourth, which had been fitted up as a snag-boat, was pushing its way down the river, removing snags, sunken logs, and overhanging trees as it advanced. During the months of September and October, sickness prevailed to such extent among the men that one-fourth to one-third of them were constantly on the sick-list, and in November, when the whole force was in good working-condition, winter rains began to set in, and by the 26th of that month the river had risen to such a height that work had to be suspended, the men discharged, and the boats laid up in a safe place for the winter, thus reducing the season's work (which is generally estimated at six) to less than three months' full work. On rivers like the Black Warrior and Tombigbee, whose bottom and shores are principally formed of materials easily moved by the current, shoals and bars are usually found where the river, by the washing of its shores, has attained an unusual width, or in some instances where an accumulation of sunken logs interferes with the free flow of the water. The general plan adopted in this improvement was, 1st, the removal of all snags and sunken logs; 2d, the construction of jetties and paral lels to contract the width of the river, and, 3d, in protecting the shores, where necessary to prevent futher abrasion. The removal of snags and sunken logs was accomplished by the snag-boat, which, however, has proved too light for the heavy strains to which she had to be subjected, and a stronger boat is being built for next season's work. Jetties and other works were constructed with the forces on the three other boats and their tenders, which latter were supplied with small pile-drivers. The method selected for building jetties and parallels was to drive piles 4 feet apart, in two rows, with 3 feet space between them; to fill in this space with closely-packed brush to 4 to 6 feet above low-water; to cap the piles crosswise to keep them from spreading; to cover the whole structure with earth and gravel, which were allowed to form their own slopes on either side. The earth penetrated and filled the interstices between the brush, so that the jetties acquired great strength in resist ing the action of the water. During last winter's heavy freshet they not only remained intact, but were strengthened by large accumulations of sand and gravel, and have in most instances already produced the desired effect of deepening the channel. Where the action of the jetties had a tendency to undermine the opposite shore, a single row of piles was driven parallel with that shore and well wattled with cane; this simple structure has been found to fulfill its purpose admirably. As soon as the river has fallen to low-water mark, a careful examination of the condition of the works and their effect on the regimen of the river will be made, to serve as a guide in planning future improvements on these rivers. During the month of June, 1876, all the boats engaged on this improvement have been put in thorough repair; a new snag-boat has been built; and should the river, as is expected, reach its low-water stage, a full force, with all necessary outfit, will begin operations during the latter part of this month, or by July 1, 1876. I append herewith a summary of amount and kind of work done on the different bars and shoals during the past fiscal year: In regard to the statistics of the trade on these rivers, I am only able to give the number of bales of cotton shipped to Mobile since September 15, 1875: Black Warrior, 30,560; and Tombigbee, 51,786. It is proposed to continue work on the improvement of these rivers during next fiscal year. Original estimated cost of the work as now being carried on for Black $151, 103 00 Tombigbee River, (see report 1870–71).. 21,500 00 172,603 00 Whole amount appropriated since the adoption of the present project.... 25,000 00 100,000 00 Money statement. Amount available July 1, 1875 Amount expended during fiscal year ending June 30, 1876.. Amonnt available July 1, 1876 . Amount appropriated by act approved August 14, 1876..... Amount (estimated) required for completion of existing project... $25,000 00 19,881 92 5, 118 08 15,000 00 132,603 00 Amount that can be profitably expended in fiscal year ending June 30, 1878. 100, 000 00 32 E I 7. EXAMINATION AND SURVEY OF THE ALABAMA RIVER, FROM WETUMPKA TO ITS MOUTH. UNITED STATES ENGINEER OFFICE, Mobile, Ala., March 8, 1876. GENERAL: I have the honor to report that the examination and survey of the Alabama River, from Wetumpka to its mouth, provided for by act of Congress approved March 3, 1875, and assigned to my charge by letter from your office, has been very much delayed by high-water in the river, which prevented an early commencement of the work, and retarded its progress at various times afterward, by sickness of the parties employed, from malarious influences; and by the severe indisposition of Mr. Yuille, assistant engineer in immediate charge of the work since the completion of the field-work, brought on by his labors in connection with it. The report and estimates, in their present condition, are forwarded now, rather than delay longer for a more perfect presentation of the subject. The examination has resulted in showing the Alabama River to be in need of and susceptible of great improvement by a moderate expendi ture. Two estimates are submitted: 1. For obtaining a channel 200 feet wide and 4 feet deep at low-water, at a total cost of $229,741. 2. For obtaining a channel 150 feet wide and 6 feet deep at low-water, at a total cost of $459,773.25. The first project is recommended as giving all that is needed at present, and should the future commerce on the river demand a greater depth, as is very probable, the money expended in carrying it out will be judiciously expended for executing the second project. A great deal of difficulty has been met with in obtaining full com mercial statistics, but such as can be will be forwarded as soon as they can be prepared. Complete details will be found in the report of Mr. Yuille, accompany. ing this. Very respectfully, your obedient servant, Brig. Gen. A. A. HUMPHREYS, Chief of Engineers, U. S. A. A. N. DAMRELL, Captain Engineers, U. S. A. P. S. The following figures have been furnished me since, by parties connected with the commerce on this river: Fifty-one thousand two hundred and sixty-eight bales of cotton have been received at Mobile, Ala., from the Alabama River since September 1, 1875, and the amount of up and down freight collected during the past year is $140,000. As at the opening of the cotton season the river is usually at a low stage of water, and boats can only carry small loads, nearly one-third of the cotton-crop tributary to this river is carried by railroad to the Atlantic sea-ports, and if is to be reasonably expected that by the proposed improvement the trade of this river will increase nearly to that extent. An appropriation of $50,000 is asked for fiscal year ending June 30, 1878. REPORT OF MR. GAVIN B. YUILLE, ASSISTANT ENGINEER. MOBILE, March 1, 1876. MAJOR: I have the honor to submit herewith my report on the examination and partial survey of the Alabama River from Wetumpka to its mouth. In obedience to your letter of instruction, dated July 27, 1875, I left the city of Mobile on the same day, and proceeded by the usual route of travel to Wetumpka, arriving there on the morning of the 28th, and took immediate steps to procure a suitable flat-boat, and arrange for necessary fitting of same for the service required. In furtherance, also, of the work in view, I was engaged some days at Montgomery in making tracings of United States township maps, embracing the Alabama River, from the records in the secretary of state's office, and in procuring other data relating to river elevations above tide-water, at points crossed by railroad surveys, obtainable from records of the railroad companies. On the 14th of August, the river at Wetumpka indicating its near approach to the usual low-water stage, and the fitting of the boat being about completed, the necessary party for the work were engaged and organized. While engaged on some examination of the river at Wetumpka, work was intercepted by heavy rains, which, extending to the upper waters of the Coosa River, caused a rise of 9 feet, delaying the start down the river till the 25th of August, when the boat was cast loose with a rise yet in the river of 3 feet above usual low-water. Admonished by the already rapid inroad of lost time upon the possible season of lowwater at command, it was not deemed prudent to attempt any extended surveys, or even a partial instrumental survey, of all the probable points requiring investigation. Taking into consideration, also, the small means at command and the many miles of river to be examined, it was determined, as the proper plan, to secure a completed general result by a careful examination of the whole river, rather than a probable incomplete result by attempting a survey of every point offering obstruction to navigation. In conformity to this plan, instrumental surveys were only made at those points where, from their magnitude or departure from the usual character of other obstructions, a survey seemed necessary to properly set forth the nature and character of it. In conducting this examination there was soon developed a similarity in the characteristics of many of the bars that was striking; so that a careful consideration of one secured a result applicable to many. Governed by these considerations of plan and economy of time and means, the examination was steadily pushed on to completion at the mouth of the Alabama River, on the 26th of October, interrupted, however, by sickness of party, and delays caused by the occurrence of several rises of the river. This completing the required examination of the Alabama River, the boat was moved on down the Mobile River as rapidly as adverse winds and tides would admit, reaching Mobile on the 30th of October, when the party was discharged, the instruments and other property properly accounted for, and I reported in person at your office for further duty. Accompanying this report are the following papers: 1. Index-map, in two sheets, Nos. 1 and 2, scale 2 inches to the mile, compiled from United States township maps, showing the entire river from Wetumpka to its mouth, with the relative position of the bars, shoals, reefs, &c., and the situation of important towns and places of trade upon and adjacent to the river, with their railroad connections. 2. Maps of surveys, in eight sheets, marked A to H inclusive, scale 200 feet to the inch, or 40, showing some of the more important obstructions to navigation. The amount appropriated for the examination not justifying any extended surveys, (as heretofore stated,) every effort was made to collect whatever data was available from railroad surveys and other sources, that had a bearing upon the object to be attained, so as to arrive at just conclusions regarding the inclination of river-bed, volume of discharge at minimum stage, and oscillation in times of flood, upon which to base a correct opinion as to the proper treatment for the removal of and the remedy for the obstructions to navigation found. Having in view, first, what may be termed a restoration of the normal capacity of the river; second, to determine the possible maximum capacity of same under a more extended improvement, with the conditions of volume, inclination of river-bed, and probable character of necessary excavations, as elements of the question. EXAMINATION AND SURVEY. The results of the examination may be briefly stated as follows: Commencing at Wetumpka, which is situated at the head of an open reach of navigable water on the Coosa River and at the foot of the last of a series of rapids that obstruct the upper portion of that river, with a width here of 400 feet, between fixed and stable banks, partly formed of gneiss rock, through which the river has made its way, it assumes a lake-like appearance, maintaining a uniform width, with a very moderate current, and depth of not less than 6 feet, till the mouth of the Tallapoosa River is reached, the junction of which with the Coosa forms the Alabama River proper. At the mouth of the Tallapoosa we come upon the first serious obstacle to navigation, caused by an extensive deposit of coarse gravel in the channel of the united rivers, brought down the former in times of flood, filling up the bed and causing a widening of the main river, with a consequent dispersion of the water into several shifting channels, through which only about 2 feet depth is found at low-water stage. The filling up of the main river, acting as a dam, has caused a great increase of the natural inclination of the river-bed below, and the formation of slack-water pools in each above the obstruction. The formation of this dam or bar in the main river is evidently the result of the very square entrance of the Tallapoosa into the Coosa, with the heavy character of deposit brought down the former and discharged into the channel of the latter, together with the very unstable nature of the adjacent river-banks, allowing an undue widening to take place with the ever-varying conditions of each river in flood and low-water. This disturbance of the otherwise favorable condition of the river continues for about 3 miles, when the normal character of the river is again found, with an increase of width to 500 feet since the accession of the Tallapoosa, and with a depth of from 6 to 15 feet in all open reaches of the river. We now enter upon a portion of the river that is very uniform in its characteristics. in the character of the banks, width and depth; also in the great similarity and nature of the obstructions found; this similarity continues so long as the river is bounded one eide or the other by high and solid bluffs. It is therefore unnecessary to enter into a minute description of the successive obstructions found; a general illustration of the governing characteristics will be more useful. The banks generally of the upper portion of the river are of a solid and firm nature. and in no case was there found any extensive caving or falling in. In a very large proportion the banks upon one side of the river or the other are composed of a compact soft rock or marl, usually called rotten limestone; a material that offers an effective barrier against the eroding action of the river, and which often contain ledges of a harder material, fit in many places for building-stone; the bluffs also contain large quantities of nodules or concretions of a hard and solid character, that fall from the face of bluff and collect at the edge of low-water, that would make suitable material for filling cribs of dams and jetties, easily gathered by boat at low-water. This general character of the river, however, is only applicable to those parts that are free from islands, bars, and shoals, of which there are great numbers, as shown upon the index-map. These obstructions may be said to have resulted from the failure in resistance offered to the action of the river by one or the other of the banks, allowing an increase of width in the flood-stage, and the consequent filling by timber, gravel, and sand in the unduly-widened river-bed during the subsidence of flood. This action has in the course of time divided the channel, forming islands and bars with those in a less advanced state, constituting the present shoals. The foregoing description of character of river applies to that portion commencing near the mouth of Tallapoosa River, and extends to a point between Claiborne and Gainstown, where the high bluffs come to an end. The width of the river in this portion ranges from 500 to 600 feet, and wherever that width is exceeded will be found the bars and shoals. In the open reaches of river ample water is always found ranging from 8 to 15 feet, and often much deeper. At none of the bars or shoals was there found any excessive current, and in the open reaches the current did not exceed ‡ or 1t miles per hour. In this really beautiful portion of the river its usefulness is marred by many bars, shoals, and reefs, and collections of logs, at many of which points the low-water depth is reduced 34, and even 24 feet. We now come to that part of the river between Gainstown and the mouth, where the width has increased to 600 and 800 feet, the depth ranging from 10 to 12 feet in the fair reaches, and upon the shoals as low as 3 feet was found for low-water. From near this point, where the high bluffs terminate, the river-banks are mostly overflowed in high-water, and are more subject to erosion by the river; a much wider scope of the valley of river is overflowed, and we find a sudden falling-off of the oscillation. One of the most damaging obstructions of the lower river is what is known as the "Cut-off," about 16 miles above the mouth of Alabama River, where the waters of the latter have of late years made an outlet through to the Tombigbee River, of such magnitude as to seriously impair the volume of water passing down the Alabama. As the Cut-off serves no useful purpose, but, on the contrary, is likely at no distant day to so lessen the volume of the main river that its usefulness will be entirely destroyed by filling up, a result that has already taken place at the head of the Cut-off in the main channel, causing a shoal of scant 4 feet at low-water, requiring the loaded steamers, either passing up or down the river, to use the Cut-off, thus leaving the main |