56th Congress, / HOUSE OF REPRESENTATIVES. \ Document 1st Session. \ ( No. 495. EXAMINATION AND SURVEY OF DIAMOND .REEF AND COENT1ES REEF, EAST RIVER, NEW YORK. LETTER FROM THE ACTING SECRETARY OF WAR, TRANSMITTING, WITH A LETTER FROM THE CHIEF OF ENGINEERS, REPORTS OF EXAMINATION AND SURVEY OF DIAMOND REEF AND COENTIES REEF, EAST RIVER, NEW YORK. March 8, 1900. — Referred to the Committee on Kivers and Harbors and ordered to be printed. * War Department, Washington, March 7, 1900. Sir: I have the honor to transmit herewith a letter from the Chief of Engineers, United States Army, dated March 6 instant, together with copy of a report from Maj. H. M. Adams, Corps of Engineeis, dated April 22, 1899, and copy of report from Maj. W. L. Marshall, Corps of Engineers, dated February 28, 1900, the former of a prelimi- nary examination and the latter of a survey of Diamond Reef and Coenties Reef, in East River. New York, made by them in compliance with the provisions of the river and harbor act of March 3, 1899. Very respectfully, G. D. Meiklejohn, Acting Secretary of War. The Speaker of the House of Representatives. Office of the Chief of Engineers, United States A rot, Washington, March 6, 1900. Sir: The river and harbor act of March 3, 1899. provided for a •reliminarv examination and survey of Diamond Reef and Coenties fceef, in East River, New York, with a view to their removal, and I H. Doc. 91 44 2 DIAMOND REEF AND COENTIES REEF, EAST RIVER, N. Y. now have the honor to submit the accompanying copy of report dated April 22, 1899, by Maj. H. M. Adams, Corps of Engineers, upon preliminary examination, and copy of report dated February- 28, 1900, with map, by Maj. W. L. Marshall, Corps of Engineers, upon survey of the locality. The plan of improvement proposed by Major Marshall provides for removing these reefs, including that part of Diamond Reef known as reef off Diamond Reef, to a clear depth of at least 32 feet at mean low water (excavation estimated to a depth of 34 feet), at an estimated cost, including contingencies, of $1,897,500. In the opinion of the local officer, improvement to the extent indi- cated is worthy of being undertaken by the General Government, and his views are concurred in by Col. G. L. Gillespie, Corps of Engineers, the division engineer. Very respectfully, your obedient servant, John M. Wilson, Brig. Gen., Chief of Engineers, U. S. Army. Hon. Elihu Root, Secretary of War. PRELIMINARY EXAMINATION OF DIAMOND REEF AND COENTIES REEF, EAST RIVER, NEW YORK, WITH A VIEW TO THEIR REMOVAL. United States Engineer Office, New York City, April 22, 1899. General : I have the honor to submit the following report upon a preliminary examination of Diamond Reef and Coenties Reef, in East River, with a view to their removal, made under authority of the river and harbor act of 1899. These reefs lie at the south end of East River, at and near its junc- tion with Buttermilk Channel and the channel between the Battery and Governors Island. New York Harbor. Diamond Reef covers an area, at the curve of 30 feet depth, about 800 feet long, with 600 feet greatest width. Coenties Reef, a quarter of a mile farther up East River, is about 280 feet long and 150 feet wide, Originally these reefs had least depths of 17.5 feet and 11.3 feet, respectively. In 1875 Coenties Reef was removed to a depth of scant 26 feet (about 25£ feet clear depth), and in 1892 the removal of Diamond Reef to 26 feet depth was completed. Between East River and North River there is a natural channel of about 35 feet depth, having a general width of 1,200 feet except for a length of 1,000 feet, where Diamond Reef, lying in the south side of this channel, reduces the width to about 200 feet. Coenties Reef lies almost directly in the axis of this narrow channel, where the harbor is \ most crowded by vessels and where the tidal currents arc very strong. These conditions make navigation there very difficult for vessels of too great draft to pass over the reefs. The river and harbor act of 1896 ordered a survey of "the channel between the Battery and Governors Island, with a view to making a| channel continuous with Buttermilk Channel thirty feet in depth and DIAMOND REEF AND COENTIES REEF, EAST RIVER, N. Y. 3 one thousand two hundred feet in width." In connection with this survey some borings were made to ascertain the area of Diamond Reef at this depth. The report, printed in the Annual Report of the Chief of Engineers for 1897, page 1182, contained estimates of cost of removing Diamond Reef and Coenties Reef to 32 feet depth. It also contained the following statements relating to the commerce of the vicinity: There are no data showing the amount or value of the commerce which passes through the channel between the Battery and Governors Island. At different times during January, 1897, for four and one-third hours altogether, the numbers and kinds of vessels passing this channel have been observed, with the following as the average result per hour: Kind of boats. Number per hour. Ferryboats Towboats without tows, and small steamers Towboats with tows Barges, etc., in tow Ships, barks, and brigs, in tow Steam lighters Large steamers Car floats Railroad ferries Total 125 Excluding the ferryboats, the total per hour is 93, of which 87 pass in midchannel or nearer the Battery shore. As nearly as can be estimated the observed traffic would be a fair average for ten hours of the day and nearly three times too great for the other fourteen hours, which would make the total traffic per day fifteen times that observed per hour. Similar observations made in summer would show a greater number of vessels; at that season there are from 50 to 100 excursion steamers daily passing the Battery, together with many pleasure boats, and large fleets of canal boats and barges from the Erie Canal and Upper Hudson, whose navigation is now [February, 1897] shut off by ice. Nearly all of the above vessels pass close to or immediately over Diamond and Coenties reefs. All but the largest boats pass over the reefs freely, but the fact that the boats of deep draft must of necessity follow a narrow course in a crowded channel creates an obstruction to vessels of all kinds. Events within the past year have demonstrated the need of a deep and unobstructed channel from the sea to the New York Navy -Yard, in East River, above these reefs. The survey of the channel between the Battery and Governors Island made in the winter of 1896-97 included borings sufficient to determine the approximate contour of these reefs at a depth of 32 feet below mean low water, and to make an estimate of the probable cost of removal. The season of the year (winter) was not favorable for making a detailed survey of the reefs, such as would be necessary before actual removal. Such a survey Avould be very expensive, under the most favorable conditions, on account of the rapid currents, the crowded channel, and the hard material underlying Diamond Reef. It could be made to best advantage during summer and fall months. ******* In my opinion the removal of Diamond Reef and Coenties Reef in East River, New York Harbor, to a depth of 32 feet below mean low water is a work of public importance, worthy to be undertaken by the United States in view of the great commercial interests involved. 4 DIAMOND REEF AND COENTIES REEF, EAST RIVER, N. Y. It is recommended that a detailed survey of these reefs be author- ized * * *. Very respectfully, your obedient servant, H. M. Adams, Major, Corps of Engineers, Brig. Gen. John M. Wilson, Chief of Engineers, U, /S. A. (Through the Division Engineer.) [Third indorsement.] Northeast Division Engineer Office, New York, May 6, 1899. Respectfully returned to the Chief of Engineers. When work ceased on Diamond Reef and Coenties Reef, the adopted navigable depth for this port was 26 feet at mean low water. Since 1892 the demand has been for increased depth extending to 35 feet, mean low water, increased to 40 feet, mean low water, over the bar at the southern entrance. The great draft of modern naval vessels and the obstruction offered to their passage up East River at low tide, notably the accident to the U. S. S. Massachusetts within the past few months, show the importance of increasing the navigable depth over the reefs in the channel leading from the navy-} 7 ard to the lower bay to 35 feet at mean low water. I therefore concur in the recommendation of *he district officer that the said reefs be lowered to the plane of 32 feet at mean low water, and that a survey to this end * * * be authorized. G. L. Gillespie, Colonel, Corps of Engineers, Division Engineer. [Sixth indorsement.] Office Chief of Engineers, U. S. Army, August H, 1899. Respectfully submitted to the Secretary of War. In accordance with the provisions of the river and harbor act of March 3, 1899, a preliminary examination has been made of Diamond Reef and Coenties Reef, in East River, New York, with a view to their removal. The localit} T is reported to be worthy of improvement, and I recom- mend that a survey be made and the cost of improvement be estimated. A. Mackenzie, Acting Chief of Engineers. War Department, August 15, 1899. Approved as recommended by the Acting Chief of Engineers. By order of the Secretary of War; John C. Scofield, Chief Clark DIAMOND REEF AND COENTIES REEF, EAST RIVER, N. Y. 5 SURVEY OF DIAMOND REEF AND COENTIES REEF. EAST RIVER, NEW YORK, WITH A VIEW TO THEIR REMOVAL. Engineer Office, United States Army, New York, N. Y, February %8, 1900. General: In compliance with Department letter dated August 18, 1899, I have the honor to submit the following; report, with estimates upon the survey of Diamond Reef and Coenties Reef, in East River, New York, made to comply with the terms of the river and harbor act approved March 3, 1899: The results of the survey and locations of the reefs are exhibited on the accompanying map. The original condition of these reefs and the reasons for their removal are fully stated in the report upon preliminary examination dated April 22, -1899, and in the report upon survey of channel between the Battery and Governors Island, printed as House Doc. No. 331:, Fifty- fourth Congress, second session, and in Annual Report of the Chief of Engineers for 1897, pages 1182 to 1185, which also contains commer- cial statistics and estimates for the removal of the reefs to 32 feet at mean low water. The commercial considerations involved in the removal of these reefs to meet the needs of navigation, both past and present, have been thoroughly reviewed in the above-mentioned reports, and in the Annual Reports of the Chief of Engineers upon the improvement of East River for the past twenty years or more. This survey has been conducted with a view of showing the character and amount of material necessary to be removed to make a clear depth of 32 feet at rnean low water over Diamond Reef and Coenties Reef, which depth is now required to meet the demands of navigation at the mouth of East River. The survey was planned and executed under direction of Lieut. Col. W. H. H. Benyaurd, by a party in charge of Mr. H. B. Gorham, assistant engineer. The held work was commenced on September 11, and completed on December 2, 1899. On account of the rapid tidal currents over and around the reefs, and the crowded condition of the channel by vessels of all classes, the floating plant required on the sur- vey had to be of the most substantial character, and after due consider- ation the large dredge Hell Gate and the tug General A. A. Eumphn ys, of the East River rock-removing plant owned by the United States, were placed in commission and used until the completion of the held work. The dredge was run into several times without causing serious damage, but upon two occasions the damage was so great as to neces- sitate its withdrawal from the work for repairs. The bills for repairs in each of these cases were paid by the owners of the vessels which caused the damage. The delays caused by collisions and a protracted period of foggy weather had the effect of prolonging the time of the survey at least a month, and thereby added considerably to its cost * * *. Experi- ence has demonstrated that it is impossible for a vessel to remain at anchor over these reefs without being run into, and there are times when moving vessels are so numerous that there is an entire block in the navigation for a short period. This fact makes it necessary to add 6 DIAMOND REEF AND COENTIES REEF, EAST RIVER, N. Y. considerably to the estimated cost of removal of these reefs, particu- larly Coenties Reef, as any plant placed there for the purpose of working upon that reef is liable to be run into and sunk at any time. The borings and soundings were taken from the dredge, which was held in a fixed position by four large anchors and chains. The borings were made with a 3-inch steel angle or drill, and with few exceptions the holes were bored through to rock bottom. The exceptions were in cases where holes were carried to the full length of the drill and no rock was found. The dredge was moved into the required positions by hauling in the chains by means of the steam windlasses or winches with which the dredge is fully equipped. In each position 2 borings and 13 soundings were taken, and by means of systematic moves the dredge occupied eight positions per hour, during which time 16 borings and 104 soundings were taken. It was found impracticable to secure accurate results by the means employed, during the full strength of the tides, consequently the work was carried on only during the period of slack tides and minimum velocities of the tidal currents. The borings and soundings were located from the dredge by sextant angles to fixed stations upon the shores of Governors Island, New York, and Brooklyn. These shore stations were located by triangulation from the bases of the United States Engineer Department and United States Coast Survey. There is a covering of loose material upon the reefs, particularly on Diamond Reef, which consists of gravel and broken stone left from former work. This loose material will be difficult to remove, and it is impracticable to make a separate estimate for its removal, as a quantity of such material will always remain lodged in the crevices all over the surface of the blasted reefs. Diamond Reef, at the 32-foot curve, at least, consists of two parts, the easterly part being known as "reef off Diamond Reef." The following estimates provide for the removal of both parts: Estimates. For removing Diamond Reef to make a clear depth of at least 32 feet at mean low water (excavation estimated to 34 feet) , 48,000 cubic yards of rock, at $30 per cubic yard $1, 440, 000 For removing Coenties Reef to make a clear depth of at least 32 feet at mean low water (excavation estimated to 34 feet), 9,500 cubic yards of rock, at $30 per cubic yard 285, 000 Contingencies, supervision, etc., 10 per cent 172, 500 Total 1, 897, 500 In my opinion the East River, New York, is worthy of additional improvement by the General Government on the plans and to the extent above set forth. Very respectfully, your obedient servant, W. L. Marshall, Major, Cordis of Engineers, Brig. Gen. John M. Wilson, Chief 'of ' Engineers, U. S. A. (Through the Division Engineer.) DIAMOND REEF AND COENTIES REEF, EAST RIVER. N. Y. 7 [First indorsement.] Northeast Division Engineer Office, New York, March 2, 1900. Respectfully forwarded to the Chief of Engineers, concurring in the views of the district officer. G. L. Gillespie, Colonel, Corps of Engineers, Division Engineer. Avery Architectural and Fine Arts Library Gift of Seymour B. Durst Old York Library