its whole extent, and a vessel could readily wait there until the services of a tug were available. The question may here be asked, why not extend the south breakwater to lap the detached work covering the entire area of anchorage just as completely against waves from the southwest as from the west ? The answer is that it has been shown by experience that such a relative arrangement is dangerous and apt to throw the entering vessel upon the detached breakwater, which would then be to leeward of the south breakwater head. In other words, this arrangement practically reproduces the vital defect of the parallel pier system, and it is better to suffer the inconvenience of a subsiding swell in a portion of the area of anchorage than to endanger the entrance by any obstruction designed to remedy an interior inconvenience. The same objection applies to an additional covering breakwater shutting off waves from the westward. The simpler the entrance consistent with absolute safety, the easier the harbor is of access, and therefore the more serviceable. Again, it may be asked, why not arrange the covering works to the southward of an extension of the north pier and thereby make a perfect lee in a southwest gale? There are practical difficulties in arranging the entrance for such a harbor as this, which it is not necessary to enumerate here; but the main objection is that the littoral current which flows from the southward would convert such a harbor in winter-time into one large field of drifted ice anchored and compacted so as to block all navigation, probably until long after it had opened elsewhere. On the other hand, under the project I have the honor to submit I should expect Ludington to be accessible by steam navigation all winter, the south breakwater being connected with the shore and effectually protecting the channel of entrance from all drift. In carrying into effect this project the first measure to be taken in hand is the south pier extension converting it into a south breakwater. Owing to the great amount of driftlogs and ice which is dashed against this pier in southwest gales, its construction must be of substantial timber work filled with stone and resting upon a firm foundation. For such a work, resting on brush mattress, which will probably be less expensive, and has been proved by last year's experience to be as unyielding and secure as a pile or stone foundation, I estimate the expense as follows: 700 feet piering, 30 feet wide, with 6 feet superstructure, in an average of 23 feet soundings, at $186 per linear foot.... 10 per cent. contingencies.. Estimated cost of south breakwater...... A pier-head 50' x 40', in 28 feet soundings, with 8 feet superstructure.. Total.... 250 feet piering, 34 feet wide, with & feet superstructure, in an average of 25 feet soundings, at $250 per linear foot.... $130, 200 The detached breakwater upon a pile foundation with stone filling, built according to the plan successfully used at Michigan City, Ind., and other places, would cost as follows: 2,000 linear feet, 40 feet wide, with 8 feet superstructure, in an average of foot.... Total.... $600,000 with 8 feet super at $265 per linear 265,000 865,000 Making allowance for the variation in cost of labor and material during the series of years through which the project would probably be in course of execution, it may be fairly estimated that it will cost from $1,000,000 to $1,500,000, depending upon the variations above mentioned and the length of time the project is under construction. The detached breakwater could be constructed of piles and mill edgings, with stone filling at the top, at a much less expense than by building in timber and stone on a pile foundation, if a method can be devised to secure the work while in process of construction. To this end I have devised a frame caisson for carrying edgings in raft in sections of 100 feet length, which I would prefer testing in shoaler water before applying the system to a work of so great depth as the one under consideration. I shall submit a project to this effect in a report upon another work to be rendered very shortly, and if the work in question is ordered will have ample opportunity to test the efficacy of this method before the time would arrive to begin the detached breakwater construction under the project herewith presented. Pile and edging construction has a record for standing a great deal of wear and tear at points as much exposed as the site of the proposed breakwater, and I do not see why it cannot be applied to advantage at this point when the mechanical difficulties and question of supply are solved. The breakwater in pile and edging construction would cost as follows: 2,000 linear feet, at $110 per linear foot... 1,000 linear feet, at $70 per linear foot.. Total.... 10 per cent. contingencies.. $220,000 70,000 290,000 29,000 319,000 Which, substituted for the $951,500 estimate for the same work in timber and stone, would reduce the estimated cost of the entire project to $547,470, or about one half. As, under the existing approved project of pier extension at Ludington Harbor, the south United States pier must be soon rapidly extended to head off the sand spit which is threatening the approach to the channel of entrance, in the event of the adoption of the project for a harbor of refuge, it would be well, while having the entire project in view, to hold the construction of the detached breakwater in abeyance until the south breakwater was completed; and if, in the mean while, experiment in the cheaper pile and edging construction should show it to be available, by its adoption the total cost of the project would be reduced onehalf, as above demonstrated. Should it be decided to construct the harbor of refuge at Ludington on the plan I propose, or any other plan involving the extension of the South United States pier, I should require for the first year $140,000 to enable me to build the first 700 feet, in order to throw out of consideration the threatened attack of sand from the southward, which, if permitted to advance and encroach in any large mass upon the channel of entrance to the interior harbor, would add an estimate for its removal or dispersion to the estimates I have already made. One hundred and forty thousand dollars is, therefore, my estimate for the first year's wo and the balance of the estimate for the south break water for the sec year, in order to complete that work in two years. The detached bre water could then be taken up, and built upon any plan, and with s degree of annual progress as might be deemed advisable and Cong by appropriation might afford. I have the honor to be, general, very servant, The CHIEF OF ENGINEERS, U. S. A. respectfully, your obedi F. HARWOOD, LETTER OF COLLECTOR OF CUSTOMS AT LUDINGTON, MICHIGAN. LUDINGTON, MICH., February 8, 188 DEAR SIR: In compliance with your request that the citizens of this place for to you an account of the wrecks on this shore and included between "Big and L Point Sable," I have compiled the inclosed statement, giving names of vessels, v of vessels, value of cargoes, total loss, number of lives lost and where lost. In compiling my statement, I have been as careful as possible, gaining my infor tion from my own books, the books of the life-saving stations, and from the older izens-reliable men. Some of the cargoes lost I could not ascertain the value of, so have left bl Any other information required please let me know, and I will give it my pers and immediate attention. Hoping this may be of much service to you, and that our legislators may recog the necessities of the proposed project, I remain, major, very truly and sincerely yours, EUGENE ALLEN, Collector of Customs for the District of Michigan, City of Ludingt To Maj. F. HARWOOD. P. S. Should some of the values prove incorrect, you will know that the accou as near as could be made. |