high is 12,333, at $30 each.... The number of gabions for both piers placed in two rows and one tier Filling the same, 77,488 cubic yards, at 50 cents... $369,990 38,744 Total 408,734 Filling same, 116,229 cubic yards, at 50 cents... Raising the piers C D and E F by a second tier will require 18,499 gabions, at $30 each..... 554,970 00 58,114 50 Additions to the above estimates by the Board: 92,496 00 30%,320 00 Being an excess over Captain Howell's estimate of.. It is difficult to estimate the cost of placing and filling the gabions, but on the supposition that an average of 15 per day throughout the year can be placed in position, it is estimated that the cost per gabion will be $10. 30,832 gabions, at $10 each, $308,320. Total Add Captain Howell's estimate... 635.401 50 1,124,000 35 Total estimate of Board for the two outer piers, if raised two tiers 1,759,401 85 R 8. IMPROVEMENT OF REDFISH BAR IN GALVESTON BAY, TEXAS. This work, for which an appropriation of $10,000 was made June 23, 1874, is but an extension of the work reported on pages 634 and 635 Report of the Chief of Engineers for 1873. The work there reported complete, answered the then existing wants of commerce. Since, a deeper and wider channel than it afforded through Redfish Bar, has become desirable. The money now available will be expended in deepening and widening the channel but is not considered sufficient to complete the work. The work is located in the collection-district of Galveston and near the light-house on Redfish Bar. Financial statement. Amount in hands of officer and subject to his check July 1, 1873. Estimate for completion of the work will be submitted in December next, it being deemed advisable to await the results of the present ap propriation before recommending another. Total amount appropriated. Total amount expended.... $20.000.00 9,961 59 R 9. SURVEY FOR LOCATING THE TERMINUS OF THE FORT ST. PHILIP CANAL UNDER THE LEE OF SABLE ISLAND. This survey was projected on the following suppositions: 1st. That a sheltered harbor excavated under the lee of Sable Island with a breakwater located on the shoal ground to the northward, if practicable, would be preferable as an entrance to the projected canal, to an entrance projected from the front of Sable Island directly into the throat of Breton Island Pass. 2d. That by inclosing Grand Bay a tidal reservoir might be established, receiving and discharging through the entrance to such harbor and thus creating currents sufficiently powerful in scouring effect to maintain the depth of entrance given to the harbor. 3d. It was assumed that this direction given the entrance would necessitate artificial works interfering the least with the flow of tidal currents through Breton Island Pass; that protection of the west end of Breton Island would be perhaps rendered unnecessary, and that a breakwater on the shoal between the east and west forks of Breton Island Pass, while protecting the entrance to the harbor from the north, might be so planned as to deepen and lengthen the west (or harbor) fork. 4th. It appeared evident that the entrance, so located, could be better protected by fortification on Sable Island than if located at any other point. The survey of 1871 and 1872 gave all the data for considering this location, except 1st. Borings and soundings along the line of probable location of the trunk of canal. 2d. For inclosure of Grand Bay. These data are now presented in the following report and on the chart herewith: UNITED STATES ENGINEER OFFICE, SIR: I have to make the following report on the "survey for locating the terminus of the Fort St. Philip Canal under the lee of Sable Island." The survey was commenced March 19, 1874, and the field-work was finished April 22, 1874. The triangulation, soundings, level-line, and sections of borings, have been plotted on a single sheet, which is submitted herewith. A tide-gange was established at Camp Howell, in Mississippi River, and another near station 6, in Grand Bay. A level-line has been run from Camp Howell to station 2, and from station 2 to the tide-gauge in Grand Bay. Taking high-water of 1874 as the plane of reference, we have plotted the section of the proposed route so as to show low-water in Mississippi River, 1872. Its reference is 6.45 feet. Extreme high-water in Grand Bay, for time covered by survey, 2.13 feet. Extreme low-water in Grand Bay, for same period, 7.03 feet. In order to preserve the record of this work five bench-marks have been established. Bench-mark No. 1 is the top of a stake at the northwest corner of the house at Camp Howell. It is 0.66 below the zero of the gauge at Camp Howell, and its reference is 0'.76. Bench-mark No. 2 is the top of a piece of 1-inch round iron, driven into the end of a yellow-pine stick, 3' by 12" by 12", buried in the ground and standing upright near the northeast corner of house at Camp Howell. It is 4.85 from the northeast corner of the house, and 15'.45 from northwest corner of the house. This bench-mark is 1.03 below the zero of the tide-gauge at Camp Howell, and its reference is 1'.13. Bench-mark No. 3 is the head of a 3-inch by 16-inch iron bolt, driven into the end of a cotton-wood log, 3 feet long, buried in the ground, standing upright, near the southeast corner of the house, at Camp Howell. It is 6'.05 from this corner and 16.05 from the southwest corner of the same house. This bench-mark is 1.83 below the zero of the tide gauge at Camp Howell, and its reference is 1'.93. Bench-mark No. 4 is a stake 82.5 from station 6, in the direction of station 2, (see chart.) The top of the stake is 2'.36 below the zero of gauge in Grand Bay. Its reference is 3'.99. Bench-mark No. 5 is the head of a g-inch by 16-inch iron bolt, driven into the end of a cotton-wood log, 3' by 15", buried in the ground, standing upright, 49 from station 21, in the direction of station 2. This bench-mark is 2.49 below the zero of the gauge in Grand Bay, and its reference is 4'.12. Seven borings have been made, 4 to a depth of 100', 1 to 97', 1 to 79', and 1 to 44. The sections of the different strata are shown on the next sheet. The specimens, 56 in number, are properly numbered for each boring, and the depth from which the earth was taken is indicated on each specimen. The location of each boring is indicated on the chart. A hydrographic survey has been made of Grand Bay. This work can be added to our general chart by reducing the scale to goo I have estimated the amount of excavation for the proposed route ( 2, to A 8, see chart) from the end of the lift-lock to 27 feet water in the Gulf, Width of canal at bottom, 200 feet; depth at extreme low-water, 25 feet; depth at mean low-water, 27 feet, (26.63.) Side slopes . The outer end of the canal to be 1,000 feet wide for a distance of 8,075 feet. Total excavation in cubic yards, 10,203,915. I have also estimated for the breakwater and jetty, indicated on the general chart. Breakwater : Breakwater to have a section similar to the construction at Rotterdam, length 11,600 Length, 11,100 feet. Depth at outer end, 11 feet. Cubic yards, fascines, and ballast, 87,704 feet. Cost, at $5 per cubic yard, $438,520. Sections of the bayous, on the south side of California and Grand Bays, have been made as directed by you. Each section is lettered, and the corresponding letter on the general chart indicates the approximate location of the section. Very respectfully, your obedient servant, Capt. C. W. HOWELL, Corps of Engineers, U. S. A. H. M. ADAMS, Lieutenant of Engineers. The work is located in the collection-district of New Orleans, near Fort St. Philip, La., and the nearest light-house is that at the head of the passes. R 10. SURVEY OF THE NECHES AND ANGELINA RIVERS, TEXAS, MADE IN COM PLIANCE WITH SECOND SECTION OF ACT OF JUNE 10, 1872. UNITED STATES ENGINEER OFFICE, New Orleans, La., December 30, 1873. GENERAL: I have the honor to forward herewith report on survey of the Neches and Angelina Rivers. The recommendations made by Lieut. H. M. Adams meet my approval. The charts to accompany this report were forwarded to the Chief of Engineers, September 29, 1873; five sheets. Very respectfully, your obedient servant, Brig. Gen. A. A. HUMPHREYS, Chief of Engineers, U. S. A. C. W. HOWELL, Captain of Engineers. |