PRESERVATION AND IMPROVEMENT OF BOSTON HARBOR; PRESERVATION OF THE HARBOR OF PROVINCETOWN; IMPROVEMENT OF THE HARBOR OF NEWBURYPORT, AND SURVEY OF THE MERRIMAC RIVER. Officer in charge, Brevet Major General J. G. Foster, lieutenant colonel corps of engineers, assisted by Brevet Lieutenant Colonel G. L. Gillespie and Brevet Major George Burroughs, captains corps of engineers. 1. Dredging off the southwest point of Lovell's Island.-The work has been carried on steadily by the contractor, who removed 66,909.54 cubic yards, widening the channel to 600 feet at the 16-feet curve, with an average depth of 162 feet. By the close of the season it is expected that this depth will be increased to 23 feet, (See Appendix S.) 2. Dredging channel across the Upper Middle Bar.-Four hundred and fifty cubic yards of material have been removed. The work has been suspended and the amount heretofore allotted for this work has been transferred to the dredging at Lovell's Island. (See Appendix S.) 3. Blasting and removing Corwin Rock.-This rock and an adjoining ledge has been entirely removed to a depth of 23 feet at low water. 1,356 tons of rock have been blasted; 1,192 tons deposited on shore, and 164 tons allowed to remain in deep water. The channel formerly between this rock and Tower Rock has been widened by the removal of these rocks from 250 feet to 600 feet. (Appendix S and S 1.) 4. Blasting and removing Barrel Rock.-A survey of this rock was made as well as contracts for its removal, and the preliminary preparations for active operations This rock has since been removed. (See Appendix S.) 5. Sea-wall at Point Allerton.-The title to the land for the site of the wall (forwarded in January last) has not received the approval of the Attorney General yet; as soon as this is obtained, proposals will be invited for the construction of the wall. (See Appendix S.) 6. Sea-wall at Gallup's Island. This work has steadily progressed; 558 feet of foundation and 456 feet of wall has been built. (See Appendix S.) 7. Sea-wall for the preservation of the North Head of Long Island.-The jury of the county court has determined upon the amount to be paid by the United States for the site of this wall, and the fortifications to be erected there. As soon as this amount is paid, either to the owners or to the judge of the court, (according to an act of the legislature of Massachusetts,) and the title receives the approval of the Attorney General, preparations for active work will be made. Estimates for the fiscal year ending June 30, 1871, for continuing the preservation and improvement of Boston Harbor, a portion of which should be made available for the present fiscal year: For dredging at Lovell's Island, to complete the work.... $75,000 00 For sea-wall at Gallup's Island, to complete 60,000 00 For dredging at Upper Middle Bar.... 100,000 00 For sea-wall at Point Allerton, to complete.. 40,000 00 40,000 00 For contingencies. Total.... 15,000 00 330,000 00 8. Preservation of Provincetown Harbor.-At Beach Point a brush bulkhead and jetties have been constructed which are fast gathering the floating sand. A dike to guard against any possible breach by the sea through the outer beach has been constructed across the Salt Meadows and East Harbor Creek at High Head. The current and tidal observations in the immediate charge of Captain George Burroughs, brevet major United States Army, have been completed. An allotment of $9,000 from the appropriation of 1869 was made for the construction of certain works for the preservation of the harbor urgently needed, which will be expended this season. Amount required to be appropriated for the fiscal year ending June 30, 1871, $25,000. (See Appendix S and S 2.) 9. Merrimac River.-Surveys have been made of the obstructions in this river, and a report with estimate of cost of removal submitted. (See Appendix S and S 3.) SEA-WALLS AT GREAT BREWSTER, DEER, AND LOVELL'S ISLANDS, BOS TON HARBOR. Officer in charge, Brevet Major General H. W. Benham, colonel corps of engineers. 1. Great Brewster.-The work of the fiscal year comprised the setting of the heavy shell-stone paving in rear of the whole of the most exposed portion of the east face of the North Head, about 700 running feet; filling the rear of about 400 feet of other portions with earth, covered in the most exposed parts with small bowlders as a temporary protection against the dash of the sea, and the construction of a strong stone pile jetty to protect the west corner of the wall of South Head. It is expected that at the close of the present working season all the work remaining to be done for the complete protection of the North Head, together with two or three jetties at the angles, will be finished, so that all that now appears necessary for the protection of the island will be completed this season, and no further appropriation for this object will be required. Amount on hand July 1, 1868. Allotted from appropriation of July 25, 1868. Expended during the fiscal year... Amount available July 1, 1869.. (See Appendix T.) 2. Deer and Lovell's Islands.-Upon the sea-wall at Deer Island 1,250 running feet of the wall of the North Head had been rebuilt and repaired up to the close of the present fiscal year, (June 30,) making in all about 2,210 running feet of wall rebuilt on the three bluffs of the island since 1865. All the most exposed parts of this wall are now repaired. The engineer in charge recommends as an additional security that some 200 or 300 feet of the North Head wall be rebuilt at a cost of about $8,000. At Lovell's Island a strong but small wall of about 800 feet in length, with four jetties at the anglés, has been built to protect the southeast bluff, which appear to answer the purpose and to increase the breadth of the beach in front of it. An apron facing of stone, protected by concrete, has been constructed in front of the eastern half of the old wall Some further repairs and a new jetty are recommended at a cost of about $2,000. IMPROVEMENT OF HARBORS IN THE STATE OF MAINE. Officer in charge, Brevet Brigadier General George Thom, lieutenant colonel of engineers. 1. Saco River improvement.-These improvements consist in the rebuilding of some of the most important piers in the river, the removal of the sunken rocks, and the construction of a breakwater at the mouth of the river. On the 30th of June, 1869, the sunken rocks had all been removed from the channel near Little Islands, and the breakwater at the mouth of the river had been partially built for a distance of 4,000 feet out from the shore, containing 51,223,5 tons of stone. The first 2,550 feet of this breakwater is built up to a general level of nine feet above mean low water, with an average thickness of twenty feet, the remaining portion forms but the "core" of the work to be built, and is barely sufficient to divert the channel as required, or to withstand the violent storms to which it is exposed. This work in its present unfinished condition has accomplished all that was expected from it. It has closed the old North Channel, (as was intended,) and formed a new one, (as was desired,) which is deeper, much more uniform and direct along the inside of the breakwater as far out as it extends, and it is apparently improving beyond that point. To complete this work in a proper manner, it must be increased throughout in height and thickness, and extended. The additional amount required for the completion of all the improvements proposed at this time (exclusive of the capping of the breakwater estimated for in previous reports) is $60,000, which amount can be profitably expended during the fiscal year, ending June 30, 1871. (See Appendix U.) 2. Extension of the breakwater and improvement of the harbor at Portland, Maine.-The capping of the unfinished portion of the breakwater has been completed, in all 733 lineal feet. Under a joint resolution of Congress, approved June 5, 1868, the harbor has also been improved by dredging a channel through the "Spit," near the "middle ground," in which there are now twenty feet of water at mean low water, or twenty-nine feet at mean high water. A contract has also been made for excavating a new channel through the "middle ground bar," to be completed on or before the first of November, 1869, and it is probable that it will be completed in that time. On hand July 1, 1868. On hand July 1, 1869.. $79,397 87 64, 491 82 Which amount will be expended by the close of this working season in deepening the channel. For finishing the breakwater, an additional sum will be required of $40,000. (See Appendix U, U 1 and U 2.) 3. Improvement of the Kennebec River, between Gardiner and Augusta, Maine. This work consists in straightening and deepening the channel of the river, by dredging through several shoals and the removal of rocks which obstruct it between Gardiner and Augusta, Maine. The width of the channel estimated for is one hundred feet at bottom, with sides having a slope of two feet to one foot rise, and a depth of seven feet up to Hallowell, and six and one-half feet thence to Augusta, at low tide in the lowest stages of the river, being about twelve feet at high tide in the same stages. The channel has been completed through Hallowell and Shepard's Point Shoal (at and below Hallowell) to a width of 75 feet, and is in progress to the same width through Britt's Shoal, above Hallowell, which will probably be completed before the 1st of October, 1869. The channel through Gage's Shoal will, it is probable, be more than half completed during the present season. About thirty bowlders have also been removed from the river at Shepard's Point, Hallowell and Britt's Shoals. The additional amount required to complete the channel from Gardiner to Augusta, (through Hinckley's Shoal and the unfinished portion of Gage's Shoal,) and to increase the width of the new channel throughout to one hundred feet, is estimated at $22,500. (See Appendix U.) 4. Improvement of the navigation of the St. Croix River, above the ledge. For this improvement it will be necessary to deepen its channel by the removal of slabs, edgings, and sawdust which for thirty years and more have been accumulating in large quantities in this river. The act making an appropriation for this improvement requires the co-operation of the province of New Brunswick, which has not yet been obtained, so that operations have not yet been commenced. Amount appropriated for this work... $15,000 00 35, 000 00 It being understood that the province of New Brunswick will contribute an equal amount for this purpose. (See Appendix U.) 5. Survey and improvements at Richmond's Island, Cape Elizabeth, Maine.-A survey of this locality has been made, with a view to forming an estimate of the probable cost of a breakwater to connect the island with the main land. Such a breakwater would form a good harbor of refuge, affording safe anchorage and good holding ground, with the wind from any point between north and southwest, affording refuge to vessels prevented by northeast storms from entering Portland or adjacent harbors. The breakwater to be permanent should be built of rubble stone, of which the engineer in charge estimates that there will be required 68,000 tons. This, when placed in the structure, would cost $93,000. Amount which can be profitably expended during the fiscal year ending June 30, 1871, $50,000. (See Appendix U.) 6. Improvement of the "Gut" Back River, opposite the city of Bath, Maine. Owing to the contraction of the channel of Back River at the upper Hell Gate, the tidal current runs through this gate with such violence as to endanger the navigation at any other time than at high and low water, except for steamers. The difficulties are still further increased by a large rock, known as "Boiler Rock," which lies in midchannel some seventy-five yards below the gate. The engineer in charge examined this rock with the aid of a submarine party. It lies in from three to four fathoms water at low tide, its highest point being only about three feet below the surface at mean low water, and ten feet below it at high water. For the improvement of navigation at this place, the engineer in charge recommends 1. Boiler Rock to be removed to a depth of twelve feet, requiring seventy cubic yards of blasting, which, at $50 per cubic yard, would cost.. 2. The point of ledge contracting the channel at Upper 3. Deepening the bar about midway between Upper Hell Total required for the proposed improvement..... $3,500 00 6, 000 00 5,500 00 1,500 00 16,500 00 All of which could be profitably expended during the fiscal year ending June 30, 1871. (See Appendix U.) 7. Survey and improvement of the Penobscot River, Maine.-This survey has been completed. Very extensive and accurate soundings and borings made in the river show that from Crosby's Narrows up to Bangor, a distance of some three and a half miles, the bed of the river is seriously obstructed with slabs, edgings, and sawdust, to an average depth of ten feet, and in some localities more than eighteen feet; and that the harbor of Bangor is also obstructed with several large sunken rocks. To restore the channel to the original river bed would require an excavation of more than 5,000,000 cubic yards of its accumulations. But a passable channel could be made at a cost estimated at from $100,000 to $500,000, according to its width and depth. (See Appendix U.) 8. Improvement of Union River, Maine.-A careful examination of this river, from its mouth to Ellsworth, has been made. The engineer in charge estimates that for the improvement of the navigation between these points, by clearing it of slabs, edgings, and sawdust, removing boulders and sunken rocks, and erecting five stone beacons, there will be required an appropriation of $40,000, which, in view of the large lumber trade, he recommends to be made. (See Appendix U.) RIVERS AND HARBORS ON THE PACIFIC COAST. Officer in charge, Brevet Lieutenant Colonel R. S. Williamson, major corps of engineers, assisted by first Lieutenant Wm. H. Heuer, corps of engineers. 1. Improvement of the Willamette River, below Portland, Oregon.—The operations on this river during the past fiscal year have been confined to dredging on Swan Island Bar, and the bar at the mouth of the river, and to removing snags at each of these localities. Surveys were made of the Willamette slough and of the mouth of the river. Many difficulties were encountered causing delays in the prosecution of the work. In December, 1868, when the dredging was temporarily suspended, a channel had been cut over Swan Island Bar, admitting vessels drawing fifteen feet, during the low water stage. The total length of channel excavated since the commencement of the work in 1867, at this locality, |