59TH CONGRESS, TWO RIVERS HARBOR, WISCONSIN. LETTER FROM THE SECRETARY OF WAR, TRANSMITTING, WITH A LETTER FROM THE CHIEF OF ENGINEERS, REPORT OF SURVEY OF HARBOR AT TWO RIVERS, WIS. APRIL 27, 1906.-Referred to the Committee on Rivers and Harbors and ordered to be printed, with accompanying illustration. WAR DEPARTMENT, Washington, April 26, 1906. SIR: I have the honor to transmit herewith a letter from the Chief of Engineers, U. S. Army, of yesterday's date, together with copy of a report, with map, from Capt. (now Maj.) W. V. Judson, Corps of Engineers, dated January 31, 1906, of a survey of the harbor at Two Rivers, Wis., made by him in compliance with the provisions of the river and harbor act of March 3, 1905. Very respectfully, WM. H. TAFT, The SPEAKER OF THE HOUSE OF REPRESENTATIVES. WAR DEPARTMENT, OFFICE OF THE CHIEF OF ENGINEERS, Washington, April 25, 1906. SIR: I have the honor to submit herewith for transmission to Congress report of January 31, 1906, with map, by Capt. (now Maj.) W. V. Judson, Corps of Engineers, upon survey authorized by section 1 of the river and harbor act approved March 3, 1905, of harbor at Two Rivers, Wis., with a view to obtaining depths of 16 and 18 feet, respectively. Two Rivers Harbor has been under improvement by the United States since 1871 and at the present time has the projected channel depth of 13 feet. In his report herewith the district officer presents alternative estimates for securing the proposed depths of 16 and 18 feet, but after discussing them at length expresses the opinion that the final cost of either plan is disproportionate to the present and prospective commerce of the locality. In forwarding the report to this Office, the division engineer, Lieut. Col. W. H. Bixby, Corps of Engineers, differs with the district officer and regards the locality as worthy of further improvement by the General Government, either by way of improving conditions in connection with the present 13-foot project, or with a view to securing increased depths, dependent upon the will of Congress, all as indicated in his report of March 7, 1906, also herewith. This report has been referred, as required by law, for review by the Board of Engineers for Rivers and Harbors and attention is respectfully invited to its report of the 11th instant, herewith. For the reasons given the Board concludes that it is not advisable for the United States to undertake the work of creating a channel depth of 16 or 18 feet into Two Rivers Harbor, and in this conclusion I concur. Very respectfully, A. MACKENZIE, Brig. Gen., Chief of Engineers, U. S. Army. Hon. Wм. H. TAFT, SURVEY OF TWO RIVERS HARBOR, WISCONSIN. UNITED STATES ENGINEER OFFICE, Milwaukee, Wis., January 31, 1906. GENERAL: 1. I have the honor to submit the following report on a survey, and an estimate of cost of the improvement of Two Rivers Harbor, Wisconsin, with a view to obtaining depths of 16 and 18 feet, respectively, in accordance with the requirements of item making appropriations for the improvement of said harbor, contained in section 1, river and harbor act approved March 3, 1905, together with a map of the survey. 2. The harbor of Two Rivers, Wis., is situated on the west shore of Lake Michigan, at the confluence of East and West Twin rivers, which unite immediately inside the shore line. This harbor is about 85 miles north of Milwaukee and about 7 miles north of Manitowoc. A projecting point of land, known as Two Rivers Point, situated a few miles north of the harbor, affords protection from northerly winds, and but little trouble is experienced from winds in the northeast quadrant. 3. Two Rivers is the northern terminus of a branch of the Chicago and Northwestern Railway, about 7 miles in length, running from Manitowoc. It has no other railroad facilities for the transportation of merchandise. An electric railway, for the carrying of passengers only, connects Two Rivers with Manitowoc. 4. The population of Two Rivers is about 4.600. The business of the place is chiefly manufacturing. Considerable fishing is also carried on from this port. The principal articles of export are hay, pease, veneered goods, and wood type; the principal articles of import are coal, coke, lumber, saw logs, and wood. 5. The original project for the improvement of this harbor was adopted March 3, 1871, and provided for the formation of a channel 13 feet deep below the datum plane of harbor improvements, which is 581.63 feet above mean tide at New York City, by building parallel piers extending to the 19-foot contour and dredging between them. The estimated cost of this project was $265,588.80. 6. In 1897 the piers terminated at the 14-foot contour, and a modification of project then adopted provided for abandoning further pier extension. At that time a channel of the required depth had been obtained at a cost of $214,500. Since then the expenditures have been for maintenance. The total expenditure to December 31, 1905, was $246,180.40, of which $31,680.40 was for maintenance. 7. At the present time the channel has the full projected depth of 13 feet, and with the exception of the superstructure on the outer portions the piers are in good condition. 8. The piers for a distance of about 1,000 feet, beginning at the shore line, are of pile construction. As originally built in 1871-1874, these piers were unprovided with sheet piling. In consequence, sand easily found its way through and the dredged channel rapidly deteriorated. In 1878-79 these piers were provided with sheet piling on their outer or lakeward faces, but the sheet piling was of an inexpensive and inferior character and as time went on it failed to afford the expected benefit. In 1903-1905 sheet-pile revetments were built along the channel faces of the pile piers. The revetments are impervious to the passage of sand and the piers are now sand proof for their entire length. 9. The outer portion of each pier for a distance of 750 feet consists of timber cribs, each 20 feet wide and 50 feet long, sunk on stone foundation. The superstructure of these cribs is badly decayed and should be rebuilt. 10. Harbor lines were established by authority of the Secretary of War on September 1, 1905, along those portions of the rivers which constitute the harbor of Two Rivers. The established harbor lines in the vicinity of the harbor entrance are indicated on the map herewith by light broken lines. It is understood that the city of Two Rivers intends to cause the rebuilding of the wharves and bulkheads, on the established lines, in the near future. 11. The inner harbor, especially in the vicinity of the harbor entrance where, at the present time the most important commercial wharves are located, is subject to great disturbance during severe storms from a southeasterly direction, the waves at times sweeping over the wharf situated immediately opposite the harbor entrance and carrying away lumber and other commodities piled thereon. * * * 12. The effect of wave action at this harbor was made one of the subjects of a report by a board of engineers appointed in pursuance of an item in section 1, river and harbor act approved March 3, 1905. This report is published in House Document No. 62, Fifty-ninth Congress, first session, to which attention is respectfully invited. On page 7 of this report it is stated The effect of wave action is much aggravated by the form of the inner harbor and by the contraction of both of the Twin rivers, which at their narrowest points are only about 110 feet in width and are protected by solid bulkheads. After passing only about 250 feet beyond the inner ends of the entrance piers waves strike a solid bulkhead standing squarely across the line of channel entrance and are reflected, producing great disturbance near the inner end of the piers and in the Twin rivers themselves. 13. After discussing the probable cause of these conditions, a method of ameliorating them is proposed by the Board of Engineers, which consists in cutting down to about ordinary lake level the revetments lately built along the channel sides of the piers from the shore line outward about 1,000 feet, and constructing thereon a sloping rubble mound above the water. 14. While this would result in an amelioration of existing conditions, it is believed it would be inadequate of itself were the depth of channel increased, thereby permitting increased wave action. Any plan of improvement involving a material increase in depth of channel should therefore provide for an additional and more effective method of reducing wave action within the harbor. This, as is stated in the report of the Board above mentioned, can be accomplished either by forming a basin of sufficient dimensions inside the main entrance, wherein the waves may expand, or by building breakwaters outside of the main entrance. 15. It is not considered necessary or advisable to extend the present piers. These piers now terminate in about 14 or 15 feet of water. From experience at other harbors in this district, notably at Milwaukee, it is believed that a depth of 16 feet or 18 feet can be maintained outside the present pierheads by dredging the exterior channel to a width of 500 feet, thereby permitting the formation of very flat slopes without encroachment upon the channel proper. 16. To obtain a suitable channel 16 feet or 18 feet deep two methods are proposed. The first method, which will be hereafter referred to as Plan A, is shown on the accompanying map by heavy broken lines; the second, referred to as Plan B, is shown by light dotted lines. 17. Plan A provides for the construction of two "stilling basins," by building two diverging piers, beginning at the inshore ends of the crib piers and extending well within the present shore line, and for dredging to obtain the desired depths. This plan provides for using as much of the present piers and channel as possible. 18. The new north pier should be a pile pier 14 feet wide, about 1,000 feet long; each wall sheeted with triple-lap sheet piles, and the pier filled with stone and riprapped. The pier should be so built that it may be cut down to a plane 2 to 3 feet below datum and provided with a concrete superstructure at some future period, if so desired. This style of pier has been constructed at Racine Harbor, Wisconsin, and has been found to be entirely satisfactory. 19. The new south pier should consist of about 350 linear feet of pile pier, similar in construction to that just described, and of about 550 linear feet of sheet-pile revetment. 20. Each of the present pile piers should then be entirely removed for a distance of about 600 feet, measured from the inshore ends of the crib piers. The partially inclosed areas thus formed should be dredged, as indicated on map, so as to form basins on each side of the dredged channel. This dredging should be as shoal as possible, being limited by the depth necessary to float a dredge and scows. The new shore line thus formed should be thoroughly riprapped to prevent erosion, and to break up and dissipate the waves. 21. It is also proposed, as suggested by the Board of Engineers, to cut down the remaining sheet-pile revetment on each side of the channel to the water surface, and to build thereon a rough rubble. mound, about 3 feet high, having a slope upward of about 1 to 5 from the channel side. 22. The land necessary for the carrying out of this project is indicated on the map by the area bounded by shaded broken lines. It should be donated to the United States by the city of Two Rivers. 23. It is believed that the waves passing beyond the inner ends of the present piers would be greatly reduced in height by these expansion or stilling basins. It is quite probable, however, that even with these basins dangerously high waves would roll into the river during severe storms, striking the solid bulkhead or "dock," so called, immediately opposite the inner end of the entrance channel, and causing great disturbance in that vicinity. 24. It is proposed that the existing bulkhead or dock be removed from the north line of Main street to the south line of Smith avenue, and that a shelving beach shall be formed along the established harbor line between said limits. This beach should be well riprapped, as in the case of the shores of the stilling basins. The waves will then expand themselves on the beach without being reflected, and the disturbances in the vicinity of the harbor entrance due to wave action will be minimized. The necessary land-indicated on map by the area bounded by shaded broken lines-should be donated to the United States by the city of Two Rivers. It is proposed that the United States shall dredge and maintain the small basin-indicated on map by heavy broken lines immediately inside of the harbor entrance, as this interior basin will then constitute a part of the harbor entrance, rather than of the inner or commercial harbor. 25. But it is doubtful if sufficient protection will by these means be afforded against very severe southeasterly storms. The worst storms at Two Rivers come from that quarter, and it is not improbable that if the depth of channel be increased to 16 feet or 18 feet, the improvements mentioned will prove to be inadequate to prevent dangerous disturbances in the inner harbor during severe southeasterly gales, and that during such storms it will be hazardous for vessels not only to enter the harbor but to be moored to the wharves in the vicinity of the harbor entrance. 26. In discussing the needs of this harbor the Board of Engineers in the report before mentioned states on pages 7 and 16: The winds complained of most by the local pilots and property owners are those from the south and east as making the entrance difficult and dangerous, and those from the southeast as specially causing waves and "undertow" between the piers and inside the harbor. Should the commerce at this harbor increase so that more dock room would be needed, and should larger vessels desire to enter the port, necessitating a deepening of the entrance which would give rise to a corresponding increase of wave action in the interior harbor, it may then be necessary to revert to the type plan already described for Ludington Harbor. In such case the first work to be done would be the lakeward end of the southern breakwater, following the type plan. 27. The "type plan" refers to an arrangement of two breakwaters, their outer ends located about 1,200 feet from the pierheads, the opening between the breakwaters being about 1,400 feet, and the axis of |