APPENDIX E. REMOVING OBSTRUCTIONS IN EAST RIVER AND HELL GATE, NEW YORK. REPORT OF BRIGADIER-GENERAL JOHN NEWTON, CHIEF OF ENGINEERS, BVT. MAJ. GEN., U. S. A., OFFICER IN charge, FOR THE FISCAL YEAR ENDING JUNE 30, 1884. UNITED STATES ENGINEER OFFICE, New York, July 30, 1884. SIR: I have the honor to transmit herewith the annual report upon removing obstructions in East River and Hell Gate, New York, for the fiscal year ending June 30, 1884. Very respectfully, your obedient servant, JOHN NEWTON, Brig. Gen., Chief of Engineers. The CHIEF OF ENGINEERS, U. S. A. REMOVING OBSTRUCTIONS IN EAST RIVER AND HELL GATE, NEW YORK. Owing to the failure of the passage of the river and harbor bill in March, 1883, it became necessary to reserve a sufficient balance to provide for the extensive and valuable plant belonging to this appropriation, and the funds so reserved have been devoted during the year to that purpose. It has been necessary to run the pumps on Flood Rock in order to keep the excavation from filling with the water which leaks through the seams of the rock, and a few men, in addition to their duties as watchmen, have been kept busy in caring for and making repairs to the machinery and stopping such leaks as were accessible. The steam-drilling scow, with all the other floating property, consisting of three steamboats, one tender scow, and one dump scow, were removed from Flood Rock in November and laid up in Gowanus Creek, as it was not safe to leave them exposed to the large quantities of ice which go with great velocity through Hell Gate. The appropriation for improving East River and Hell Gate for the year ending June 30, 1885, is limited in its application to "removing the reef at Hell Gate." A hitherto unknown rock off Twentieth street, East River, has been recently struck by one of the Boston passenger steamers, and has been 5908 EN- -44 689 found to be of small size but dangerously near the deep-water channel A reef with 21 feet at low water also exists about 150 yards northeast of the place occupied by Diamond Reef previous to its removal. These two rocks, together with Pot Rock and the remains of the Frying Pan Rock, constitute serious obstructions to deep-water navigation. I append herewith the report of Capt. James Mercur, Corps of Engineers, who is on duty in connection with this work. The original condition of the channel of East River and Hell Gate was the existence of many large and dangerous rocky obstructions to navigation. The depth over Diamond Reef at mean low water was 171 feet; over Coenties Reef, 14.3 feet; over Frying Pan, 11 feet; over Pot Rock, 20 feet; over Heel Tap, 12.1 feet; over reef at the North Brothers, 16 feet; Hallet's Point from the shore at Astoria projected under water 325 feet to the contour line of 26 feet at mean low water, and embraced an area of about three acres. The Middle Reef, with an area of about nine acres, lay in the middle of the channel at Hell Gate, having a small backbone projecting above high water, and caught vessels swept upon it by the ebb currents, which passed directly over the rock. Hallet's Point and the Middle Reef may be said to have been alternate in mischievous functions; vessels which escaped one ran a great risk of falling upon the other. What added considerably to the danger from these reefs was the bend at right angles of the river at this spot. The originally adopted project for the improvement was the least extensive of three projects discussed by the engineer in charge. That one now being carried out was judged by the authorities in 1867 to be too extensive and costly. The project first adopted was the removal of Pot Rock, Frying Pan, Way's Reef, Shelldrake, the rock off Negro Point, the rocks near Wolsley's Bath-house, Blackwell's Rock, portions of Hallet's Point and Scaly Rock. Sea-walls were designed for the Middle Reef, Hogsback, the Bread and Cheese, and a beacon for Rylander's Reef. The project most favored by the engineer in charge, which included likewise the total removal of Hallet's Point and of the Middle Reef has, as time passed, received the approval of the authorities. The project first intended solely for Hell Gate has also been modified by incorporating with it rocky obstructions in the East River, Diamond Reef, Coenties Reef, and a reef near the North Brothers. 'The amount expended thereon to the close of the fiscal year ending June 30, 1883, was $3,136,945.28. The condition of the improvement was the removal of Diamond, Coenties, and Way's reefs and Shelldrake to a depth of 26 feet at mean low water; the breaking up of Heel Tap Rock, the tunneling and explosion of Hallet's Point, and the removal of the débris to the depth of 26 feet at mean low water; the tunneling of the Middle Reef (Flood Rock) to the extent of 23,180.9 linear feet, and the removal therefrom of 70,347.9 cubic yards of stone, measured in place; the removal of the reef off the North Brother's Island to a depth of 26 feet at mean low water. The amount expended during the year ending June 30, 1884, was $25,098.03, and has been for running pumps to keep Flood Rock clear of water and for watching and preservation of the property. During the year ending June 30,1885, the available balance, $371,878.87, will be applied to extending the galleries in about three-quarters of an acre, drilling about 5,000 feet of 3-inch holes in the reef and all the holes in the pillars for the final blast, which, it is expected, will take place about September, 1885. The amount that could be profitably expended in the fiscal year ending June 30, 1886, is $500,000, which should be expended as follows: For completing excavation at Flood Rock, $60,000; for removing Pot Rock and Frying Pan in Hell Gate, and a reef near Diamond Reef in East River, $180,000; for grappling and removing in part the broken stone after explosion of Flood Rock, $260,000. The total cost of removing the débris from the explosion would probably amount to $600,000. The estimated amount required for the entire and permanent completion of the work of improvement in accordance with the approved and adopted project is $1,602,963.67. This work is in the collection district of New York. The nearest port of entry is New York City. The amount of revenue collected during the year ending June 30, 1884, $135,093,152.62. The amount of commerce and navigation benefited by the completion of this work, about $4,000,000 daily. ORIGINAL ESTIMATE. Removing reefs at Hell Gate and Diamond and Coenties reefs... $5, 139, 120 AMOUNTS EXPENDED DURING THE YEAR ENDING JUNE 30, 1884. July 1, 1884, amount expended during fiscal year, exclusive of outstanding liabilities July 1, 1883 July 1, 1884, outstanding liabilities.. $21,773 40 23, 907 55 Amount (estimated) required for completion of existing project. 1,602, 963 67 500, 000 00 REPORT OF CAPTAIN JAMES MERCUR, CORPS OF ENGINEERS. NEW YORK, July 22, 1884. SIR: I have the honor to submit the following report upon the work of removing obstructions in East River and Hell Gate, New York. Lieut. George McC. Derby has been in superintendence of this work under your personal direction up to April 8, 1884, and since that time under your orders as transmitted through this office. Owing to the lack of funds due to no appropriation being made for the fiscal year ending June 30, 1884, it became necessary to stop active work on May 31, 1883, and reduce the expenditures to those necessary for the preservation of the work already done and the care and preservation of the plant on hand. At Flood Rock all leaks were gone over and plugged and wedged as tight as possible, reducing the leaks as measured from 737 gallons per minute, at the beginning of the year, to 565 gallons per minute at this date. A number of changes in the manner of running the pumps were made during the year by Lieutenant Derby, resulting in a large saving in the amount of coal required for pumping. The most novel of these changes was connecting three pumps so that the exhaust steam from the first worked the second, and that from the second worked the third, instead of supplying each with steam direct from the boiler. This allowed the use of steam at a pressure of from 60 to 70 pounds to the inch to be supplied to the first pump, which gave about 40 pounds to the second and 20 pounds to the third, the expansion being obtained by increased speed in the second and third pumps, instead of by increased area of piston, as in the ordinary compound engine. Without this device the steam pressure had to be relieved to about 20 to 25 pounds to the inch by throttling in order to give the pumps a safe speed. So far as I know this is a new device. A small force of machinists has been kept at work putting the drills, compressers, &c., in-order, and the floating plant has been watched and kept in good repair, the tug-boat Gen. A. A. Humphreys and the dumpscow have been docked and made tight. A portion of the holes for the final blast were drilled before the beginning of the year; these have been surveyed and plotted, and some of the computations necessary for the distribution of the charges for the final blast have been made. The drilling scow, which at the beginning of the year was at work at New Rochelle, finished the work there and was laid up at Flood Rock in August, 1883, where she remained until the approach of winter necessitated placing her in a berth secure from running ice. The scow, with the rest of the floating plant, was removed to Gowanus Bay, South Brooklyn, in November, 1883, where it has remained up to date. It will be necessary to put the drilling scow in dock and thoroughly caulk her seams before putting her at work for another season, as she has now been in service and subject to the action of ship worms for six years since she was last out of water Respectfully submitted. Brig. Gen. JOHN Newton, Chief of Engineers, U. S. A. JAS. MERCUR, Captain of Engineers. |