REPORT OF THE ENGINEER OF THE WASHINGTON AQUEDUCT. DEPARTMENT OF THE INTErior, OFFICE OF THE WASHINGTON AQUEDUCT, Washington, D. C., October 1, 1866. SIR: In compliance with the regulations for the government of persons employed upon the Washington aqueduct, approved August 18, 1863, I have the honor to submit the following report for the year ending September 30, 1866: At the date of the last annual report the work on all the unfinished portions of the aqueduct was entirely suspended. An estimate of the cost of completing the Washington aqueduct was submitted with the report, but Congress did not make an appropriation for completing any portion of it until the close of the session. The following is a copy of the correspondence in reference to the resumption of work on certain portions of the aqueduct : DEPARTMENT OF THE INTERIOR, Washington, D. C., August 6, 1866. SIR: The act of Congress approved July 28, 1866, entitled "An act making appropriations for sundry civil expenses of the government for the year ending June 30, 1867, and for other purposes," contains the following items, viz: “To complete the dam in the Potomac river at the head of the aqueduct, from the shore to Conn's island, with cut stone, $51,687; to complete the connecting conduit around and outside the receiving reservoir, $70,897; to finish gate-house at Great Falls, $14,000; for temporary dam at Conn's island, $1,000; for management, miscellaneous, and contingents, $15,000.” I request that you will report to me as speedily as possible whether, in your opinion, the works thus provided for could not be re-let to responsible contractors, after due notice, at rates below those at which they were last let. I am, sir, very respectfully, your obedient servant, THEODORE B. SAMO, Esq., JAMES HARLAN, Secretary. Engineer in Charge Washington Aqueduct. [Extract from letter sent in reply to the above.] DEPARTMENT OF THE INTERIOR, OFFICE OF THE WASHINGTON Aqueduct, SIR: In reply to your communication of this date requesting me to report whether, in my opinion, certain portions of the Washington aqueduct could not be re-let to responsible contractors at rates below those at which they were last let, I have to state that, in my opinion, no responsible contractors would be willing to undertake to complete the works for less than the present prices. I considered the present contracts advantageous to the government when the work was last let, and during its progress and since its suspension I have seen no reason why I should change the opinion then formed. The work on the dam and on the connecting conduit was let at the lowest prices offered, as will appear by reference to the enclosed comparison of bids. I am, sir, very respectfully, your obedient servant, Hon. JAMES HARLAN, Secretary of the Interior. THEODORE B. SAMO, Engineer in Charge. DEPARTMENT OF THE INTErior, SIR: I have received your report of yesterday, in answer to my communication of same date, touching the resumption of work on the Washington aqueduct. Relying upon the opinion expressed by you that the works in question cannot be re-let to advantage to the government, you are authorized to direct the contractors to resume their work with every practicable despatch, giving special attention to the construction of the dam. I am, sir, very respectfully, your obedient servant, THEODORE B. SAMO, Esq., JAMES HARLAN, Secretary. Engineer in Charge Washington Aqueduct. DEPARTMENT OF THE INTERIOR, GENTLEMEN: You are hereby ordered to resume the work embraced in your contract of July 30, 1864, for the construction of the Potomac dam across the Maryland channel of the Potomac; also the work embraced in your contract of August 2, 1864, for the construction of the connecting conduit around the receiving reservoir, and so much of the work embraced in your contract of August 18, 1863, as pertains to the gate-house at the Great Falls. The work on the Potomac dam must be begun on the 9th instant, and continued as rapidly as possible until its completion. The work on the connecting conduit must be begun on or before the 13th instant, and continued in like manner. I am, gentlemen, very respectfully, your obedient servant, Messrs. DUNBAR, SHERRILL & BANGS, Contractors Washington Aqueduct. In compliance with the above order the construction of the dam and of the connecting conduit was resumed on the 9th and 13th of August respectively, under the immediate supervision of Charles H. Sherrill, esq., the managing head of the firm. POTOMAC DAM. It is much to be regretted that the appropriation was not made early in the spring, so that the work could have been resumed immediately after the spring freshets had subsided, and fully completed by the 1st of December. Since the resumption of work on the dam it has progressed in a satisfactory manner. The accommodation roads and bridges which were washed away in the spring of 1865 have been rebuilt; the excavation for the foundation is over half done; fully one-half of the foundation masonry is built, and the superstructure masonry is commenced. Unless the work should be delayed by high water, I am of the opinion that by the beginning of December the foundation masonry will be completed across the Maryland channel to Conn's island. The excavation for the foundation has been deep and expensive in many places, but the solid rock bed of the river has been reached at every point. Previous to the resumption of work on the dam an estimate was made of the damage it had sustained during the two years that the work was suspended, which is as follows: 987 cubic yards of back filling, washed away during the spring freshets, at $3 50 650 cubic yards of excavation, from trench previously excavated, but filled up during the spring freshets, at $2 50 Total... $3,454 50 1, 625 00 5,079 50 No damage has been done to the unfinished masonry, which has withstood successfully the heavy spring freshets of the Potomac for two successive seasons. TEMPORARY DAM AT CONN'S ISLAND. As was predicted in the last annual report, this structure was washed away by the spring freshets of 1866. It was thoroughly repaired in August, and will probably not require any further expenditure. GATE-HOUSE AT GREAT FALLS. Thus far it has been a difficult matter to get mechanics to work at Great Falls. The place has the reputation of being extremely unhealthy, and malariuos fevers prevail to an alarming extent. The mechanics of Georgetown and Washington will not work there when they can procure employment in the city. The force of masons at present at work was brought from New York city. It being doubtful whether the gate-house could be finished before winter, it was deemed advisable not to begin its construction until early next spring, but to keep all the force that could be procured at work upon the dam. CONDUIT FROM GREAT FALLS TO THE DISTRIBUTING RESERVOIR. The conduit has been in almost uninterrupted use since December 5, 1863 All parts of it appear to have been built in the most substantial manner, and since July, 1864, not a dollar has been expended on any portion of it for repairs. Several of the embankments, with the completion of the Potomac dam, will require an increase of material over the crown of the conduit, in order that it may be used to its full capacity. The road over the conduit, which for the want of money has had very little attention paid to it during the past year, is now being graded and put in good condition. BRIDGES. No appropriation was made at the last session of Congress for completing the stone bridges on the line of the aqueduct. An estimate of the amount required was submitted to the department a year ago; the same estimate is again respectfully submitted. The necessity for completing these bridges is no greater now than it was then, only it is more obvious. Bridge No. 3, seventyfive feet span, and bridge No. 4, Union Arch, two hundred and twenty feet span, and which costs about $237,000, have been for nearly three years in their present incomplete condition. CONNECTING CONDUIT. The work on the connecting conduit was suspended April 1, 1865. It was resumed August 13, 1866, after a lapse of over fifteen months. During the suspension this portion of the aqueduct sustained very little damage; the excavation in a few places caved in and filled the trench which had been prepared for the masonry. This work is now being vigorously prosecuted, but was begun too late to insure its completion the present year. DISTRIBUTING RESERVOIR. No work has been done on the construction of the distributing reservoir since June, 1864. Since then it has been in constant use for storage and settling purposes. At the flow-line it has an area of forty-four acres, and the waves have considerably damaged its unprotected banks. The inhabitants of Georgetown and Washington are indebted to it for their constant supply of clear water. It is difficult to determine how it can now be dispensed with. The influent, effluent, and auxiliary gate-houses, in connection with this reservoir, are in the same unfinished condition that they were a year ago. The longer they are left in their present state, the greater must be the final cost of completing them. GOVERNMENT MAINS AND IRON BRIDGES. The mains which have been laid by the government have an aggregate length of 17 miles. During the past year no leaks or breaks of any importance have occurred. On Pennsylvania avenue, near the Wallach school-house, the 12-inch main has been uncovered by the alteration of the street grade, and will require to be either lowered three and a half feet below the present grade or incased in a stone gallery. The tubular bridges over College pond and Rock creek are in good condition. The hand rail of the latter has been newly painted; the tubes and spandrels require painting, and an estimate for that purpose is submitted. WORTHINGTON WATER PRESSURE ENGINE. This engine supplies Georgetown heights with Potomac water. It has been in perpetual motion the past year, and is in good condition. The high service reservoir on Georgetown heights, which is fed by this engine, has during the past year been in constant use; it is unfinished and should be completed without delay. FINANCIAL STATEMENT. At the date of the last annual report there remained unexpended of the appropriation made July 4, 1864... Received from the Washington and Georgetown Railway Company from one-half the cost of the new floor of bridge 6 Balance transferred by Clem. L. West, esq. Received from the sales of property.. Total $7,058 00 649 88 301 16 100 00 8, 109 04 On July 28 Congress appropriated for the Washington aqueduct $142, 584 00 Received from sales of property. Balance in treasury as above 320 00 2 23 142, 906 23 Total.. The expenditures to date are as follows: Existing liabilities August 1, being for engineering, superintendence, and repairs.... Engineering, superintendence, repairs, and contingents, from August 1 to date... Repairs of temporary dam at Conn's island Construction of Potomac dam.... Construction of connecting conduit Balance in the treasury applicable to this work, October 1, 1866 $4, 280 92 2,985 89 486 02 10,602 45 7, 352 91 117, 198 04 Total 142,906 23 Estimate of the cost of completing the Washington aqueduct. STONE BRIDGES NOS. 1, 2, 3, AND 4. |