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APPENDIX B B B.

WASHINGTON AQUEDUCT--INCREASING THE WATER SUPPLY OF WASHINGTON, DISTRICT OF COLUMBIA-ERECTION OF FISHWAYS AT GREAT FALLS.

REPORT OF COL. GEORGE H. ELLIOT, CORPS OF ENGINEERS, OFFICER IN CHARGE, FOR THE FISCAL YEAR ENDING JUNE 30, 1894.

1. Washington Aqueduct.

2. Increasing the water supply of Washington, D. C.

3. Erection of fishways at Great Falls.

OFFICE OF THE WASHINGTON AQUEDUCT,
Washington, D. C., July 1, 1894.

GENERAL: I have the honor to transmit herewith report of operations for the following works in my charge for the fiscal year ending June 30, 1894, viz: Washington Aqueduct; increasing the water supply of Washington, D. C.; erection of fishways at Great Falls. Very respectfully, your obedient servant,

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GEORGE H. ELLIOT,
Colonel of Engineers.

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WASHINGTON AQUEDUCT.

Appropriations for the Washington Aqueduct are applied to the improvement, the maintenance, and repair of those portions of the Washington water supply, other than the tunnel from the distributing reservoir to the new reservoir near Howard University, that have been placed under the supervision of the Chief of Engineers. The works include the masonry dam, 2,877 feet long, extending from the Maryland to the Virginia shore at Great Falls of the Potomac, 14 miles west of Washington; the works at Great Falls for regulating the supply of the conduit; the conduit from Great Falls, 9 feet in diameter; the three reservoirs, viz, the Dalecarlia receiving reservoir, about 4 miles west of the city, the distributing reservoir, about 2 miles west of the city, and the high service reservoir in Georgetown for the supply of the higher portions of that city; the mains by which the water is

carried from the reservoirs and delivered into the city's distributing system, and the bridges for supporting the mains across Rock Creek. The following statement exhibits the condition of the aqueduct and its accessory works, and the operations of the last fiscal year:

THE DAM AND OTHER WORKS AT GREAT FALLS.

Advantage was taken of the very low condition of the Potomac in August to replace the riprap back of the dam that had been carried away by ice in the two preceding winters. Five hundred and one cubic yards were used for this purpose at the dam across the Virginia channel and 405 cubic yards at the dam across the Maryland channel, making a total of 906 cubic yards. This work had been postponed on account of want of funds for the purpose.

A new frame was made for the screen at the intake of the conduit. The painting of the machinery that operates the valves in the gate house and the roof of the gate house were commenced in June and nearly completed.

On December 21 there was introduced into the Senate of the United States and referred to the Committee on the District of Columbia a bill entitled "A bill to amend an act approved July 15, 1882, entitled An act to increase the water supply of the city of Washington and for other purposes."" The bill provided for the acquirement by the United States by the right of eminent domain or otherwise, of so much of the land and water rights at Great Falls as might be deemed necessary for the present and future water supply of the District of Columbia. It also provided for securing by the United States to its co-owners in the land and water rights at the falls, by contracts, the right to use and the facilities for using the remainder of the flow of the river, and for the ascertainment and payment of damages for the land and water rights taken under the act of 1882.

In the report on the bill which I made on March 20, and of which a copy will be found in Appendix 3, I endeavored to show that while the remainder of flow above mentioned would amount to five-sevenths of the low-water flow and sixty-three sixty-fifths of the average flow, the riparian rights of the United States at Great Falls are so extensive that the Government appears beyond all question to own by far the greater part of all the water flowing at that point; that, therefore, it would be unwise for the United States to enter into the contracts referred to, but that on the contrary it should proceed to acquire by the exercise of the right of eminent domain, or otherwise provided for in the bill, all of the water and water rights at Great Falls not now owned by it, to the end that the United States for itself and the District of Columbia could not only increase from time to time and without limit and without further controversy with its co-owners (the Great Falls Manufacturing Company and the Chesapeake and Ohio Canal Company) the supply for ordinary purposes, but could utilize the remainder for power to be used in the generation of electricity for the lighting of the public buildings, the public grounds and streets of Washington, for the pumping of water to the higher levels of the city, and for other public purposes.*

A delay in submitting this report enables me to also append hereto (see Appendix 6) a report of a board of engineer officers, dated July 18, 1894, upon the feasibility and advisability of using the water power of the Great Falls of the Potomac or other water power in the neighborhood of Washington, D. C., for the purpose of lighting by electricity the public buildings, grounds, and streets of the District of Columbia.

These suggestions were approved by the committee, and the bill as amended now pending (S. 1359 and H. R. 7280, Fifty-third Congress, second session) provides for legislation that is of the highest importance to the United States and the District of Columbia, and in respect of the water supply of Washington more important than any that has been enacted since the completion of the aqueduct thirty years ago.

It is understood that the property has recently been offered for sale to private parties at the price of $350,000, and I think that there can be no doubt that it can be acquired by the process provided for in the bill at a fair and reasonable price, fair to the United States and the District of Columbia, and fair to the co-owners.

The importance of early action in this matter is stated in the report of the Senate Committee on the District of Columbia in the following terms:

If the entire power at Great Falls is acquired, we believe it will be ample for electric lighting and pumping purposes for the city. The Great Falls Power Company have very recently obtained new charters from the legislatures of Virginia and Maryland. Their purpose is evidently to develop the power and supply it directly, or through other companies, to the city for lighting and other purposes. There are no improvements now at Great Falls except the Aqueduct dain, built and owned by the United States. If the Government is ever to acquire control it should be done before any outlay is made by the other owners. Such outlay must be to them a questionable investment, in view of the fact that the Government is sure to require an increased supply from time to time in the future, thus endangering the business of the power company and destroying or greatly lessening the value of their improvements, with the risk that they may not be sufficiently recompensed. Your committee are therefore of the opinion that all the water and riparian rights at Great Falls necessary for the control and use of the entire power should be acquired at this time; that it will be a wise economy to do so; that ownership in part by the United States and in part by private business corporations is a relation unwise and unsafe for the Government, and should be terminated at once; that the other owners can offord to surrender their rights now on much better terms for the Government than after they have made their improvements, and that no outlay of money can contribute more than this to the future welfare of the capital of the country.

There is another reason why the bill should be acted upon at the earliest possible moment.

There is immediate necessity for raising the dam at Great Falls, and in my estimates appended to this report will be found an estimate of $125,000 for the work. An explanation of the same will be found under the title "Explanations of estimates."

Not since the 48-inch main was laid have there been so many complaints of want of water as during the present summer, not only in the higher portions of that part of the city supplied by gravity, but in other portions of this area from which complaints have never come before. I am informed that many houses, including some of the better class as far down as Lafayette Square, are losing their tenants because they can not get water in their bathrooms, and it is feared that pecuniary loss, sickness, and inconvenience will result from this state of affairs. The District authorities are extending the area of high service (to which water is pumped from the United States mains) to Tennallytown, Brightwood, and other places in the "county." As this will make a new and increased demand on the mains, it is certain that the deficiency in the portion of the city supplied by gravity will soon be greater than it is now, and the only remedy, other than the stopping of unnecessary and avoidable waste by the enactment of a law requiring the use of meters by all consumers of Potomac water, is the raising of the dam.

When the dam was last raised and extended to the Virginia shore

(the work was finished in 1886), increasing the supply to the city about 25,000,000 gallons per diem, it gave rise to extraordinary claims for damages on the part of the coowners with the United States of the land and water rights at Great Falls, amounting to hundreds of thousands of dollars, which have not been settled to this day. In my judgment but a very small portion of these claims is justly due, but whatever be paid on them will have to be paid jointly by the United States and the District of Columbia.

For the reason, therefore, that the respective amounts of water to which each of the three riparian owners at Great Falls is entitled have never been judicially determined, they should be so determined, or, if it be possible, the United States should acquire all of the water at the Falls in the manner proposed, before another increase in the height of the dam be made.

I should further remark in connection with this subject, that the object of raising the head of water at the in-take of the conduit is to increase the velocity through the conduit, and thus enable it to bring more water down from Great Falls and into the distributing reservoir, to the end that the water in this reservoir may be kept up to its proper height of 146 feet above datum. It may be found, however, that even with the water in the distributing reservoir at this height, it will not restore the pressures in the city (which by reason of the rapid increase in consumption and waste, are constantly falling), to what they were when the 48-inch main, which I laid in 1890, was first put in operation.

In this case, it will be necessary at once to finish the tunnel connecting the distributing reservoir with the new reservoir near Howard University, or to lay another 48-inch main from the distributing reservoir to and through the city. It should be understood, however, that neither of these is the alternative of raising the dam at Great Falls, which must be done in any case, and with the least delay practicable. Estimates for raising the height of the dam at Great Falls, for the protection of the inlet to the Aqueduct, and for the construction of a storehouse at Great Falls, will be found in the list of estimates appended hereto, and explanations of the same will also be found further on in this report under the title "Explanations of estimates."

THE RESERVOIRS.

A portion of the land required for the improvement of the Dalecarlia receiving reservoir, for which an appropriation of $60,000 was made in the act of Congress of March 3, 1893, was acquired by the purchase of five parcels, the areas and the dates of the deeds of which, as well as the dates of their record, will be found in the following table. The deeds are recorded at Rockville, Md., in the office of the clerk of the circuit court of Montgomery County. Boundary stones have been planted at the corners of these lands.

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One and forty-two one-hundredths acres of land were also obtained by lease from Ignatius Belt, for one year from July 10, 1893, with the privilege of extending the same for one or two years longer, at the option of the United States, for the purpose of constructing thereon the temporary buildings required.

The preparatory work of this improvement, a description and the plans of which were contained in my last annual report, commenced on July 5. A road was graded extending from the Conduit road at the western foot of Dalecarlia Hill to the mouth of the proposed tunnel near waste weir No. 2 of the Washington Aqueduct, to be used for hauling the compressor and other drilling plant and the materials required for the work. A wooden flume 250 feet long, 4 feet wide, and 12 inches high was constructed from the mouth of the tunnel leading from the waste weir to Little Falls Branch, which flume was made necessary by the leakage from the gates in the dam of the waste weir, which ran directly over the site of the portal of the proposed main drainage tunnel. A magazine of rubblestone was constructed in the valley of Little Falls Branch, above the reservoir, for the storage of dynamite. A blacksmith shop, a storehouse, and other necessary buildings were constructed at points convenient to the work, and a building was hauled from the Champlain avenue shaft of the tunnel leading to the new reservoir near Howard University, to serve as the office of the assistant engineer in local charge of the work. A railway about 500 feet long was constructed for the transportation of material, and a telephone line, connected with this office, was run to the work.

For the purpose of guarding the proposed shaft in the valley of Little Falls Branch and the hoisting machinery in floods, a temporary dam was constructed across the branch at a distance of about 100 feet from the site of the shaft, and the channel of the branch was changed from the west to the east side of the valley. Careful surveys were made along the route of the proposed open channels between East and Mill creeks and between the latter and Little Falls Branch, and borings were made on the sites for the permanent dams across these streams. Contracts were made with the Ingersoll-Sergeant Drill Company, of New York, for furnishing a 40-horse power boiler, an air compressor, and other machinery required for driving machine drills; with McMa han, Porter & Co., of New Cumberland, W. Va., for re-pressed vitrified bricks for the invert, and with the Frederick Brick Works, of Frederick, Md., for common bricks for the main body of the lining of the tunnel and for the shaft; with James H. McGill, of Washington, D. C., for Cumberland hydraulic cement, and with the American Forcité Powder Manufacturing Company, of New York, for dynamite and exploders.

As soon as the water from Waste Weir No. 2 had been turned into the flume and disposed of (July 17), work on the rock excavation of the open cut was commenced with a gang of drillers and laborers. On the 24th another 8-hour shift was put on, and on the 29th the excavation of the open cut was completed by the removal of 538 cubic yards of rock. Its total length is 70 feet.

On August 1 the excavation of the tunnel was commenced, and from the 3d of that month, when the third shift was put on, until its completion on February 6, it was carried on night and day, except on Sundays and holidays. The excavation, by hand drilling, of the shaft in the valley of Little Falls Branch was commenced on October 12, and was completed to the top of the space to be occupied by a water cushion on January 8. The excavation of the tunnel from its north

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