D 2. HEADQUARTERS CORPS OF ENGINEERS, Washington, D. C., January 27, 1869. GENERAL: In compliance with the resolution of the House of Representatives, dated January 6, 1869, I forward a "copy of the report.of General T. J. Cram, of the Engineer Department, upon the examination and survey for a ship canal on the prolongation of the lower reach of the Maumee River through the shoal water of Maumee Bay, Ohio, directly to deep water in Lake Erie, with plans and estimates of the cost of constructing the same." In transmitting this report I beg leave to state that the project, as presented by General Cram, has not my approval, being objectionable both as to location of proposed canal and as to plan of construction. I am of opinion that the depth of water expected to be secured by the construction of this canal not only will not be maintained, but that the work itself will tend to seriously impair the navigation through Maumee Bay, and the present outlet of Maumee River. In view of the importance of this work, the project of General Cram was submitted to a board of officers of the corps of engineers of special experience in lake-harbor works, who were instructed to "Take into consideration the plan submitted by Brevet Major General Cram, dated December 27, 1868, for the improvement of the entrance into the Maumee River, and in so doing consider the relative advantages of continuing the present plan of widening and deepening the track vessels now used in passing through Maumee Bay, and that of a new cut from deep water in Maumee River to deep water in Lake Erie. "If such a cut or canal is deemed feasible, its proper direction, its width, and the protection required for its banks, will be determined as well as its cost. The cost of executing each project discussed will be submitted. "The board will determine, as a preliminary step in its proceedings, what increased depth of entrance is required at this harbor for the greater economy and security of lake navigation, in view of the growing wants of commerce." The report of the board is transmitted. herewith. I concur with the board in its deductions and conclusion, "that the improvement of this harbor should be effected by dredging the main or western channel," and have to request that this report may be forwarded to the House of Representatives with the special report called for. General Cram estimates the cost of the improvement by his project, giving 13 feet depth, at $885,526. The board estimate the cost of the improvement, using the western. channel and giving 13 feet depth, at $124,212. Very respectfully, your obedient servant, A. A. HUMPHREYS, Brigadier General of Engineers Commanding. Major General J. M. SCHOFIELD, Secretary of War, War Department. Report upon the examination and survey, with plans and estimates, of the cost of constructing a ship canal in the direction of_the_prolongation of the lower reach of the Maumee River, directly across the shoal, Maumee Bay, into deep water of Lake Erie; by Brevet Major General T. J. Cram, colonel corps of engineers, in accordance with authority from the Chief Engineer, dated September 1, 1868. 1. REASONS FOR CONSTRUCTING THIS PROPOSED SHIP CANAL. In my annual reports of 1867–268, cogent reasons have been urged for stopping further expenditures upon the plan of widening the vessel tracks as they now pass through the bay, and deepening them to 12 feet, as we have been doing the past two seasons, under the appropriations of 1866-67, amounting to $40,000. The examination and survey, continued up to the close of the present dredging season, give us the data for arriving at the measure of the advantages and disadvantages to be expected from continuing the present plan of improvement, which I will here briefly present: On chart A I have located this improvement by the red dotted lines extending from buoy No. 9-the present mouth proper of the river-to buoy No. 7, a distance of 1 mile, in which we have dredged, so that we now have 170 feet width and 12 feet depth of channel in low water of the season of navigation, excluding those occasional gales from the west, when the water is blown from the bay, so as to lower it by 3 to 4 feet. The total amount dredged for this improvement has been 82,469 cubic yards, including dredging away the troublesome elbow near the mouth, the whole costing under the contract $35,200 50. It is very true that this improvement has relieved the navigation very much of the difficulties vessels have heretofore encountered in this reach, so much that none have been reported as having grounded here this season. The difficulties now are further out on both vessel tracks, where, in several places, the shoalness is such that they frequently ground in adverse winds, at the angles of the tracks, mostly, but sometimes even in the straight parts of the courses. These groundings became so frequent that I directed the inspector of dredging to keep a record of the number and time of detention of all that should come under his observation. His report has been rendered and shows that from the 15th of August to the 18th of November, 1868, 102 vessels grounded, and the average detention for each was 13 hours; some were detained as long as 48 hours. These detentions, bear in mind, occurred in only three (3) months of the season of navigation. It is difficult to estimate the money loss, to ship and freight owners, of these detentions. My examinations have also been extended to the questions of damage, lighterage and lights required by reason of the shoalness of the water, and the angles, or crookedness, of these vessel tracks; and I cannot set their aggregate measure in cost at less than $25,000 per season. Others set it much higher. To estimate the cost of completing the improvement by the mode we have been pursuing for the past two seasons, by dredging these tracks to a depth of 12 and width of 200 feet, I take as a basis of calculation the cost of what we have already accomplished, premising that for each mile as we should go further out, the expense of dredging, from increased risk of the dredges, tugs, and scows being driven away, and detention by the frequently passing vessels, would increase in the ratio of 20 per cent. for every successive mile over the cost of the preceding mile. Upon the foregoing basis I make the cost of dredging for completing the eastern track.. And of the west track.. And of completing both without any dikes.. $423,386 00 252,710 00 676,096 00 Should one be improved without the other there would be times when no vessel could pass in or out; hence discontent, unless both should be improved, and it would be necessary to improve both if we expect by this plan to render the bay a fit harbor of refuge in all weather. The east channel would be 6.811 miles long between the river's mouth and lake, and the west 4.943 miles long. And after dredging them to this cost, they would most undoubtedly fill up within a few years; and their angles, or crookedness, at all times would be serious hinderances to the passage of vessels under strong winds from almost any quarter. 2. PROPOSED STRAIGHT SHIP CANAL. The examination and surveys which have been especially made for this, lead us to a location for the canal represented in fine red lines, extending from 13 feet depth of water in the lower reach of the Maumee River, as seen on Chart A. This chart shows the soundings made twelve years since. Map B also shows the location of the canal, and the soundings and borings made in September and October, 1868. On a careful comparison I find that near the mouth of the river and for some distance out, there has been a filling up in the past twelve years for at least 18 inches; but as we go further out, and especially out into the lake beyond North Cape Point, the changes have not been so great. It is impossible to compare with mathematical nicety the soundings of our recent with those of the former survey-owing to the bench mark of Chart A not having been recovered; it has been lost, as mentioned on the chart. In our estimates, therefore, we are to be guided not by Chart A, but by Map B, whose plan of reference for the soundings is the surface of the water at the low stage during the season of navigation, excluding the extraordinary fluctuations already referred to. Another point: Our examinations clearly show that without much greater expense the new canal cannot be made with more than 13 feet depth of water below this low stage-which has been fixed and marked as our "standard stage;" and this is the stage designated "surface of water" in the drawings accompanying this report. There will be three divisions of the canal, viz: 1st division-from C, which we have permanently located in mouth of the river, to D, at the shore line of the cape on the bay side, an extent of 4,720 yards. 2d division-from D across the ground of the cape, which is above water, to d' at the lake shore line, an extent of 360 yards. 3d division-from d' to d", which is a point in 13 feet water in the lake, an extent of 2,270 yards. Therefore, from 13 feet water in mouth of the river to 13 feet water in the lake, the total length of the proposed canal will be 7,350 yards, or nearly 4 statute miles. The mean of all the soundings in 1st division is 8.12 feet. The mean rise of ground above water in 2d division is 1.15 feet. The mean of all the soundings in 3d division is 8.518 feet. CROSS SECTION OF PROPOSED CANAL. In my judgment, for the present and for some years to come, the wants of the general commerce for refuge, and the immediate commerce of Toledo, would be amply provided for by making the canal 200 feet wide at bottom and 260 feet at the water surface, in 1st division; and 300 feet wide at bottom and 252 feet at water surface, in 2d division; and 250 feet wide at bottom and water surface in 3d division. On the east, or bay side of the canal, in 1st division, there should be constructed of wood, with the earth dredged from the canal, a good dike, or revetment, with its face next the canal, vertical-to prevent the heavy bay waves coming from the east, from breaching through the canal bank into the canal; on the land side such a revetment would not be necessary. The canal side there should have a slope and berm; the slopes to be 1 on 2. This, in after time when increased commerce will need it, would allow the canal to be widened 25 or 50 feet, without sacrificing any of the first construction. On both sides of 2d division there should be slopes of 1 on 2, then a berm and an embankment; there would be no necessity of revetments, or defensive dike like that for the 1st division. On both sides of 3d division parallel piers should be extended out at first into the lake only to 10 feet water, having a width of 250 feet between them. This would be for the outer harbor of refuge, and a greater width I think unnecessary, and it would for all time satisfy the increasing wants of the commerce. The earth, however, must be excavated in this division to allow the cribs of the piering to stand in 13 feet water; and that excavated from between the piers to be used in part for filling the cribs up to the water surface, the remainder of the pier filling to be of rubble stones, and the remainder of the earth excavation to be thrown over back of the piers and put in proper shape. Of course, the dredging for the canal is to be extended beyond the piers, to the 13 feet curve in the lake. Sheet C shows the cross sections in each division in all the mathematical details and dimensions, drawn to a scale and with an "equalization of excavation and embankment." The tops of the banks in each division are to be 5 feet above the surface of the water. The excavation in 1st division would be.. 540,450 cubic yards. Total excavation for the canal and piers, 1,016,680 cubic yards. The embankments for the 2d division require only 15,308 cubic yards to make them; the surplus of 113,910 cubic yards is to be brought back to help make the west embankment of 1st division. The mean distance this surplus will have to be moved is 13 mile, all by water. The borings at six different places along the line of the location, show that the material to be dredged is just what contractors desire for their machines to work in, and that it is of very easy nature for dredging. It is also good for driving piles into and holding them after being driven. The design for the wood work of the dike, first division, is shown in all necessary details in sheet D; it is essentially the same as that which in every respect has proved perfectly successful for the new St. Olan flats improvement, and we need have no hesitation in adopting it for the Maumee construction. Even though the waves should wash away the earthen part of the embankment the wood work would remain intact and its sheet piling would prevent the earth from being driven into the canal. I think it would be quite sufficient to make this revetment for an extent only of 11,610 feet. The pier work in third division I would only at first extend from d' to the 10-feet curve-a distance of 1,300 yards-but dredge out to the 13-feet curve as before stated, waiting to see whether it would be necessary afterward to extend the piers further out. In my opinion the power of the outflow of this river through such a channel would keep the new canal clear of deposits quite out beyond the 13-feet curve, after dredging out to that depth, without prolonging the piers. The force of outflow is a question to which our examination and survey were extended, and my assistant, Captain G. I. Lydecker, corps of engineers, presents the following results of his experiments upon this subject: "In the reach chart A from red buoy No. 6 to black buoy No. 13, a distance of 1,300 yards, he found the surface velocity to be 0.39 mile per hour; and by a float extending below the surface 0.20 mile per hour-a light southwest breeze blowing during the experiments." He is of the opinion that under ordinary "circumstances the current in the lower part of the river is mainly if not wholly due to the winds. Thus a strong northeast wind breaks the water from the lake and bay up the river, giving, as long as it lasts, a strong current, uprising the water in the bay and lower reach of the river from 2 to 3 feet above its ordinary level. When the lull comes the water rushes out to re-establish the equilibrium and a strong down current results. And, vice versa, a strong wind from the southwest produces corresponding but opposite currents to those mentioned above as due to a northeast wind. During the day and night previous to his experiments a strong southwest wind had prevailed and the water in that reach and bay had fallen 10 inches. "But in freshets, especially those of spring-time, the outflow is very powerful, notwithstanding the winds from the quarters mentioned, and outward currents obtain for seven to ten days." The effect of these in clearing the canal, if properly made from deposits, would undoubtedly be successful. On the contrary, such an effect can never be hoped for in a division of the force of this outflow between two crooked channels, such as we have at present and should continue to have by improving ever so much the east and west vessel tracks. The view I take in respect to filling the piers of the third division, is to fill the lower parts with stone ballast for a height of three feet, thence to the water surface with the materials we dredge from the water-way between the piers, and thence four feet higher, with rubble stone to the bottom of the upper timbers of the superstructure. The cribs should be fastened in place by a pile driven in each interior corner. The effect of which I know from my own experience, when the piles are properly driven, would be to keep the cribs from careening while they settle. In this locality the borings lead to the belief that after dredging to a depth of 13 feet, the foundations will admit of close bottoms to the cribs. Should it be found otherwise in the process of construction, the tight flooring could be left out and the cribs would then have a single grating bottom. Sheet E shows the drawings of the cribs and superstructure. |