At the time of the survey the surface of low tide at the dam was 3.29 feet higher than at the steamboat wharf. High tide at the steamboat wharf rose 5 feet, and at the foot of the dam only 1.8 feet, thus making the high-water surface nearly level. The lower miter sill of the lock is 5.5 feet below low tide at the foot of the dam, and only 2.21 feet below low tide at the steamboat wharf. The difference in level be tween miter sills of the lock is 15.39 feet. The top of the dam is 17.11 feet above low tide, and 15.31 feet above high tide at its foot, and 7.22 feet above the level of the upper miter sill of the lock. One thousand and fifty feet above the steamboat wharf the river is crossed by a wagon bridge, and 850 feet farther up it is crossed by the bridge of the Maine Central Railroad. Neither of these bridges have drawspans. The lower chord of the wagon bridge is 33.4 feet above low tide, and 28.4 feet above high tide. The lower chord of the railroad bridge is 46.86 feet above low tide, and 43.60 feet above high tide. About two years ago the wagon bridge was rebuilt. The old bridge had two spans with one pier near the middle of the river, and the new bridge has three spans with two piers in the river, one on either side of the old central pier. The masonry of this old pier was taken down but the crib-work foundation still remains and there is only 14 feet of water on it at low tide. The channel between this old foundation and the new easterly pier has a width of only 75 feet. From the steamboat wharf to the wagon bridge there is a channel depth of 10 feet or more at low tide. Between the bridges there is a shoal 500 feet long with a depth on it of only 24 feet at low tide. Just above the railroad bridge there is a shoal 300 feet long with a least depth of 2 feet, and at the entrance to the lock another shoal with a depth of less than 2 feet on it at low tide. The great difference in level of 3.29 feet between low tide at the foot of the dam and at the steamboat wharf of course gives rise to a very strong current. Most of this difference in level is taken up on the shoals above and below the railroad bridge, and the current is so strong at low tide that it is almost impossible to row up in a small boat. From the dam to Vassalboro, 12 miles above the steamboat wharf at Augusta, the river is simply a mill pond, and has a barely perceptible current. This portion of the river varies in width from 500 feet to 1,100 feet, and has a navigable channel from 10 feet to 30 feet deep. Five miles above Augusta there is a small island in the river known as Five Mile Island. There is, however, a good navigable channel on either side of it. From Vassalboro to the foot of the rapids at Carters Ledges, a distance of 24 miles, the river shoals rapidly, and there is a navigable channel through this portion of only 6 feet depth. Between the foot of the rapids at Carters Ledges and Waterville, a distance of 3 miles, the water surface has a slope of 8.63 feet. Most of this slope occurs on the three shoals with which this part of the river is obstructed, and which are known as "Carters Ledges," "Pettys Rips," and "Fort Point Rips." At the time of the survey the current over these shoals was so swift that the only way to ascend them with a small boat was by towing along shore. Opposite the steamboat landing at Waterville there is a basin having a depth of more than 17 feet. At the lower end of this basin, and about one-fourth of a mile below the steamboat landing, there is the shoal known as "Fort Point Rips," which has a least depth on it of 1.8 feet. In a length of 2,100 feet on this shoal the slope of the water surface was 2.5 feet. From the foot of Fort Point Rips to the head of Pettys Rips, a distance of 6,100 feet, there was a fall of 1.74 feet. Between these shoals there is a navigable channel 5 feet deep, obstructed at one point only by a shoal 100 feet long on which there is a least depth of 4.6 feet. At Pettys Rips the channel is very narrow and has a least depth of 2.5 feet. In a length of 2,800 feet over this shoal there is a fall of 2.44 feet and 1.5 feet of this fall is taken up in a distance of 900 feet at the head of the shoal. From the foot of Pettys Rips to Carters Ledges, a distance of 4,200 feet, there is a fall of 0.8 foot. Through this pool there is a channel 5 feet deep obstructed at one point by a shoal 350 feet long, on which there is a least depth of 4.1 feet. At Carters Ledges the bottom of the river is almost all solid rock, and ledge crops out above the water surface in a number of places. There is a practicable channel between these ledges which has a depth almost the entire distance of 6 feet or more, but at one point it is obstructed by ledge, on which there is only 4.4 feet. For a length of 1,000 feet over this shoal there is a fall in the water surface of 1 foot and a further fall 0.15 foot to the foot of the rapids, a distance of 800 feet. At Fort Point Rips the shoal is caused by bowlders and coarse gravel. Nine tests of the bottom were made on this shoal by driving a steel rod from 6 to 8 feet below the water surface without encountering ledge above a depth of 6 feet. At Pettys Rips an irregular reef of ledge extends from the eastern bank nearly across the river, leaving a channel ouly 75 feet wide along the westerly shore. This channel is obstructed by bowlders and coarse gravel, and by tests made with the steel rod underlying ledge was found to extend across the head of the channel at a depth . of 5 feet below the water surface. The width of the river between Vassalboro and Waterville varies from 400 to 800 feet, the general width being 500 feet. The banks of the river throughout the entire distance from Augusta to Water ville are stable, being generally coarse gravel or ledge, with sand a small part of the distance. At only three places is any marked eaving taking place, and at these points it is not great enough to be of any serious consequence. For a number of years past the river has been used almost exclusively for the floating of loose logs from the headwaters of the Kennebec and its tributaries to the mills along the banks, or to a point 2 miles below Augusta, where they are made into rafts to be transported farther down the river. The value of these logs when sawed is estimated at over a million dollars annually. This industry is managed by a company which has almost completely appropriated the river as a flume for its logs during five or six months of the year, and has by means of piers, buoys, and chained logs constructed booms, which, in several places, have entirely closed the channel to navigation during the logging season. At the time of the survey the "drive" was at its height, and the logs interfered greatly with the work, and in three or four places were so jammed as to make a satisfactory examination impracticable. The present steamboat navigation of the river consists in a light-draft stern-wheel boat built between two and three years ago by a company of citizens of Waterville, to ply between Augusta and that point. This boat proved to be of greater draft than was expected, drawing when loaded about 24 feet of water. For this reason it could only run for a month or two in the spring and before the water had dropped to summer level. Beside the shoal water it had to contend with the floating logs which at some of the worst places, especially Pettys Rips and Carters Ledges, occupy the entire channel. The improvement desired seems to be for practicable navigation for light-draft boats and barges from Augusta, the present actual head of navigation, to Waterville. These boats and barges would be used for transporting bulky freight, mostly coal, up the river. The Maine Central Railroad follows the river closely from Augusta to Waterville, but it is claimed by citizens of Waterville that by making the river navigable the saving in freight rates to Waterville would be large enough annually to justify a moderate expenditure for the improvement. The trouble caused by floating logs would have also to be in some way abated to make navigation safe. To force the logging company to raft their logs below Waterville would be so expensive as to seriously cripple the industry. The only practicable method would appear to be to compel the logging company to construct a boom almost the entire length of the river which would leave a channel free from logs and sufficient for safe steamboat navigation. At the narrow places where it would be impracticable to divide the channel a sufficient force of men would have to be kept on duty by the logging company to check back the logs at such times as steamboats wished to pass. The simplest improvement for the upper part of the river would be the construction of a lock and dam at Carters Ledges, or at Vassalboro, but the cost (roughly $125,000) would be out of proportion to the benefits to be derived and would still leave the part of the river below the dam to be improved. Another objection to this plan of improvement is that by raising the water high enough to give a navigable depth at Fort Point Rips the water power at Waterville would be to some extent interfered with. The estimate herewith submitted is to obtain a channel 60 feet wide on the bottom and 5 feet deep at the stage of water to which the soundings on the map are referred. Such channel could be obtained by dredging, at all the shoals except Carters Ledges where the removal of a small amount of ledge would be necessary. This width and depth for the channel was fixed upon as they are the greatest which can be secured without removing large quantities of ledge. At extreme low-water stages there would be at least 1 foot less depth on the shoals, leaving a navigable depth of not more than 4 feet at such stages after the improvement is completed. The material to be dredged is all coarse gravel and bowlders. The rock to be removed at Carters Ledge is solid ledge. The prices given in the estimate are based on the expectation of the work being done by contract, and above the dam competition would be limited to such small dredges as can pass through the lock. A lump sum of $500 is added to the estimate for the removal of bowlders from the channel between the points to be dredged. The channels proposed have been made as nearly straight as practicable while following closely the line of deepest water. The locations of the proposed cuts are marked on the tracings submitted. ESTIMATE. Dredging coarse gravel and bowlders below dam at Augusta, 11,548 cubic yards, in scows, at $1.25. At shoal below Pettys Rips, 1,100 cubic yards, in scows, at $1.50 . $14,435.00 1,650.00 7.837.50 At shoal above Petty Rips, 300 cubic yards, in scows, at $1.50. Total....... 450.00 33,850.50 $25.00 500,00 4,252.00 45,800.00 If it should be thought advisable to add 50 feet to the length of the lock at Angusta, an improvement which is said to be desired, $25,000 would have to be added to this estimate, making a grand total of $70,800 as the cost of the whole improve ment. Very respectfully, your obedient servant, Lieut. Col. PETER C. HAINS, Corps of Engineers, U. S. A. F. S. BURROWES, APPENDIX B. IMPROVEMENT OF CERTAIN RIVERS AND HARBORS IN MASSACHUSETTS. REPORT OF LIEUTENANT-COLONEL S. M. MANSFIELD, CORPS OF ENGINEERS, OFFICER IN CHARGE, FOR THE FISCAL YEAR ENDING JUNE 30, 1892, WITH OTHER DOCUMENTS RELATING TO THE works. IMPROVEMENTS. 1. Newburyport Harbor, Massachusetts. 5. Harbor of refuge, Sandy Bay, Cape 6. Gloucester Harbor, Massachusetts. 10. Winthrop Harbor, Massachusetts. UNITED STATES ENGINEER OFFICE, Boston, Mass., July 8, 1892. GENERAL: I have the honor to transmit herewith annual reports for the works of river and harbor improvements in my charge for the fiscal year ending June 30, 1892. Very respectfully, your obedient servant, Brig. Gen. TпоMAS L. CASEY, S. M. MANSFIELD, Lieutenant-Colonel of Engineers. Chief of Engineers, U. S. A. B I. IMPROVEMENT OF HARBOR AT NEWBURYPORT, MASSACHUSETTS. Newburyport is situated on the south bank, 23 miles approximately, from the mouth of the Merrimac River. The river empties into the Atlantic Ocean midway between Cape Ann and Portsmouth, or about 30 miles a little east of north from Boston in a direct line. The outlet of the river between Plum Island and Salisbury Point is 1,000 feet wide and 30 feet deep at mean low water. At a distance of nearly a mile outside lies a sandy bar, thrown up by wave action, through which, previous to the improvement, a channel, variable in position, direction, and depth, was maintained by the current of the river, increased by the tidal prism in a large interior basin, due to a range of tides equaling 73 feet. For 1,000 feet outward from the gorge toward the crest of the bar the current was able to maintain a channel of navigable width and 18 feet deep at mean low water, and for a further distance of 1,500 feet a channel 12 feet deep. From the 18-foot contour line on the inside to the same on the outside the distance was 4,000 feet, and between the 12-foot contours the distance was 3,000 feet. The depth on the crest of the bar was generally less than 7 feet at mean low water. The object of the improvement is to create through the outer bar a channel 1,000 feet wide and at least 17 feet deep at mean low water, so that vessels may cross the bar and find a harbor at any stage of the tide, with as great draft as can reach Newburyport by the river at high tide. The project submitted September 16, 1880, proposed two converging rubblestone jetties, their outer ends parallel for 1,000 feet, and about the same distance apart, and the protection of the beach in their vicin ity. This was modified in 1882 so as to provide for the partial closing of Plum Island Basin, with a timber dike about 800 feet long and 5 feet above mean low water. The direction of the south jetty and the character of the shore protection was modified in 1883. The north jetty, from Salisbury Beach, is to be 4,000 feet long, approximately, and the south jetty, from Plum Island, is to be 2,400 feet long, approximately. Both are 15 feet wide on top, which is in a plane 12 feet above mean low water. The two jetties have slopes of 1 on 2 on the sea side, and of 1 on 1 on the harbor side. A map showing the location of the jetties is published in the Annual Report of the Chief of Engineers for 1885. Their form and dimensions are shown in the Report for 1881. The location and details of construction of the dike are given in the Report for 1883. The estimated cost of the improvement was $375,000. The total appropriations to date have been $257,500. On June 30, 1891, the condition of the improvement was as follows: The north jetty was completed for 2,300 feet in length, and 375 feet in addition were partly completed; the south jetty had been completed 1,077 feet, and partly completed for an additional length of 223 feet, and its shore end had been strengthened by a durable sand catch; the dike had been completed so far as was prudent at the time for its safety. It was 817 feet long, 5 feet high above mean low water, except that near its center a weir had been left 150 feet long and 2 feet above mean low water. The least depth in the channel across the bar was 12. 1 feet at mean low water. Operations were in progress under a contract with Mr. J. H. White to deposit in the north jetty 10,000 tons, more or less, of rubblestone, This contract was completed during the year; a total of 11,445 tons of rubblestone was deposited under it, and the north jetty was com pleted for a length of 2,485 feet. During the latter part of June, 1892, a survey of the bar was made. It shows that the channel crossing the bar has changed but slightly in direction since the survey of 1891, but has deepened so that the least depth at mean low water is 13. 1 feet in a navigable channel at least 200 feet wide. The distance across the bar between the 18-foot contours is 2,100 feet. On the outside of the bar some advance of the deep-water contours is noticed. Inside the bar and between the jetties, no important change is noted in the deep-water contours. At the date of this report the north jetty is completed for a length of 2,485 feet, and partly completed for 190 feet in addition. The south jetty and the dike are in the same condition as on June 30, 1891. From notes furnished by Mr. Hiram F. Mills, engineer of the Essex |