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maintenance, is about 15 feet, and that when greater depths are given there is a tendency to shoal. Under the existing project of 18 feet the annual maintenance charge is about $40,000, and it is reasonably certain that this sum would be greatly exceeded if additional depth were given. The better facilities provided by the existing project have not been followed by a corresponding increase in commerce. On the contrary, the tendency is in the other direction. Expenditures already made, together with those required for maintenance, are believed to be all that present and immediately prospective traffic warrant, and therefore the board concurs in the opinion of the district and division engineers that it is not advisable at this time for the United States to undertake any additional improvement of Winyah Bay, S. C.

8. In compliance with law the board reports that there are no questions of terminal facilities, water power, or other related subjects which could be coordinated with the suggested improvement in such manner as to render the work advisable in the interests of commerce and navigation.

For the board:

PETER C. HAINS,

Major General, United States Army, Retired,
Senior Member of the Board.

PRELIMINARY EXAMINATION OF WINYAH BAY, S. C.

WAR DEPARTMENT,

UNITED STATES ENGINEER OFFICE,
Charleston, S. C., May 10, 1917.

From: The District Engineer Officer

To. The Chief of Engineers, United States Army (through the Division Engineer).

Subject: Preliminary examination of Winyah Bay, S. C.

1. Authority. In compliance with letter from the office of Chief of Engineers, dated August 4, 1916, I submit report of a preliminary examination of Winyah Bay, S. C., made in accordance with an item of the river and harbor act approved July 27, 1916, as follows:

The Secretary of War is hereby authorized and directed to cause preliminary examinations and surveys to be made at the following-named localities, and a sufficient sum to pay the cost thereof may be allotted from the amount provided in this section:

Winyah Bay, S. C., with a view to securing a channel of increased depth and adequate width from a point on the Sampit River one mile above the limits of the city of Georgetown to the entrance of Winyah Bay.

2. Locality. Winyah Bay lies on the coast of South Carolina, 90 miles southwest of the entrance to Cape Fear River, N. C., and 50 miles northeast of Charleston Harbor, S. C. At its head and on the left bank of the Sampit River, lies the city of Georgetown.

3. Maps.-Maps of this locality have been published as follows: (a) C. & G. S. Chart No. 428-"Winyah Bay, S. C.," showing channels and shore topography in detail.

(b) C. & G. S. Chart No. 153-" North Island to Isle of Palms," showing general vicinity and inland waterways.

(c) "Post Route Map of South Carolina," showing railways and connections, rivers and postal routes.

4. General description.-Winyah Bay is an irregular crescentshaped tidal estuary some 16 miles in length, measured from the bar to the mouth of the Sampit River. At the gorge or entrance between North and South Islands it is about three-fourths of a mile wide, and then broadens out into an expanse known as Mud Bay, 4 miles in width, very shallow, and broken up by low marsh islands. In its upper part the bay is 14 miles in width. The navigation channel follows the western and southern shore.

The bay at its head receives the waters of the Waccamaw, Great Peedee, and Sampit River systems. The Great Peedee is a continuation of the Yadkin River, which rises in the mountains in the extreme northwestern part of North Carolina, and is joined at various points in its course by the Lumber, Little Peedee, Lynches, Black, and other rivers. By means of the Estherville-Minim Creek Canal, Winyah Bay is connected commercially with the Congaree-WatereeSantee system of rivers, and also with the inland waterways down the coast to Charleston. It is calculated that this bay is the outlet for waterways having an aggregate navigable length of 802 miles for steam and power boats of various capacities, and for pole-boat or flat-boat navigation such as obtained in earlier days the aggregate length is 1,023 miles.

5. Previous reports.-Previous reports on Winyah Bay and Georgetown Harbor have been made and published as follows:

(a) The river and harbor acts of July 4, 1836, and August 30, 1852, carried appropriations of $1,000 and $3,000, respectively, for surveys of the bar and harbor of Georgetown. The reports of these surveys are not available at this time.

(b) In compliance with an item in the river and harbor act of June 14, 1880, a survey was made of Georgetown Harbor, the report of which was printed on pages 1036-1038 of the Annual Report of the Chief of Engineers for 1881. The district engineer officer recommended improvement by dredging a channel 12 feet deep and 200 feet wide across the bar at the mouth of the Sampit River in Winyah Bay at an estimated cost of about $14,000.

(c) A partial survey of the bar at the mouth of Winyah Bay was made in 1881. The report was published as Senate Executive Document No. 46, Forty-seventh Congress, first session, and was reprinted on pages 1122-1127 (with map) of the Annual Report of the Chief of Engineers for 1882. The report was favorable to improvement by means of jetties at an estimated cost of $1,500,000, but recommended that more detailed surveys be made prior to beginning of construction work.

(d) A preliminary examination and survey of the entrance to Winyah Bay was made in 1884. The report was published as House Executive Document No. 258, Forty-eighth Congress, second session, and reprinted on pages 1154-1170 (with map and diagram) of the Annual Report of the Chief of Engineers for 1885. This report contains considerable data as to currents, with an analysis of the effects to be expected under certain hypotheses, and sug

gests and discusses various sites for jetties with corresponding estimates of cost. The report was favorable to improvement by means of high stone dikes or jetties, constructed by certain defined stages, at an ultimate cost of $2,500,000, the purpose being to give a depth of 15 to 20 feet over the bar. The report, however, left open for subsequent determination the bar channel to be improved, and the exact location of the jetties.

(e) The river and harbor act of August 11, 1888, directed that a board of engineer officers be convened to consider and report upon the plan for improvement of Winyah Bay entrance, submitted by the district engineer officer in 1885, as described in the preceding paragraph. The report of this board was submitted in December 1888, and was published as House Executive Document No. 117, Fiftieth Congress, second session, and was reprinted on pages 1110-1115 (with map) of the Annual Report of the Chief of Engineers for 1889. The board recommended improvement of the northerly channel across the bar-known as Bottle Channelby the construction of two jetties, designated as north and south jetties, projected respectively from islands of the same names, and extending to the curve of 18-foot depth on the seaward side of the entrance bar. The board recommended 3,000 feet as a tentative distance between the outer ends of the jetties, subject to revision based on observation of the effects during the various stages of construction. The cost was estimated at $2,500,000, and was based on the supposition that adequate funds would be provided and that the work would be rapidly carried to completion.

(f) The river and harbor act of March 3, 1899, contained an item calling for a preliminary examination of "Sampit River: From its mouth at the 20-foot depth at low water in Winyah Bay to its head of navigation, with the view of dredging shoals and removing obstructions." The report of this examination and subsequent sur vey was published in House Document No. 387, Fifty-sixth Congress, first session, and was reprinted on pages 1883-1893 of the Annual Report of the Chief of Engineers for 1900. The district engineer officer recommended that Sampit River be improved by dredging to give a depth of 20 feet from its mouth in the upper end of Winyah Bay to the upper limit of the city of Georgetown, at an estimated cost of $275,000. From the upper city limit to the head of navigation, the channel was to be 6 feet in depth at a cost of $33,542.52. The division engineer did not concur in the recommendation of the district engineer, stating that, as the project then in force called for a depth of 15 feet over the bar, and as there were in Winyah Bay a number of shoals affording a 13-foot depth only, the deepening of the Sampit River proper to a depth of 20 feet was needless and premature. Consequently, by direction of the Chief of Engineers, the district engineer submitted an estimate of $428,845 as the cost of dredging through the shoals of Winyah Bay to give a channel 400 feet wide and 20 feet deep. The aggregate cost of such a channel from the upper limit of the city of Georgetown to the ocean bar, exclusive of the 6-foot channel in the upper river, thus amounted to $703,845. (g) The river and harbor act of June 13, 1902, ordered a preliminary examination of "Georgetown Harbor, with a view to obtain

ing a channel with a navigable depth of 18 feet at mean low water, and a width of 400 feet, or such width as may be necessary or practicable, from a point 1 mile above the limits of the city of Georgetown, in Sampit River, to the ocean entrance of Winyah Bay, S. C., as far seaward as may be necessary to form a project to secure said depth." The report of examination and survey was published (with map) as House Document No. 298, Fifty-eighth Congress, second session, and reprinted (without map) on pages 1591-1609 of the Annual Report of the Chief of Engineers for 1904. This report contains a discussion of plans for improvement by way of two routes, designated as eastern and western channels, respectively. The district engineer recommended the former as the most economical, but the division engineer, and the Board of Engineers with the concurrence of the Chief of Engineers, recommended that the 15-foot project then in force be modified so as to provide for an 18-foot channel as proposed by the act, at an estimated cost of $650,000, inclusive of the balance of the funds then on hand. The improvement was to be made by way of the western channel, and was to be accomplished by means of dredging and by the construction of a training wall to deflect the current into the concave bend along the western shore. This report is, in fact, the basis of the existing project adopted in 1910, and now completed except for the construction of the training wall.

(h) The river and harbor act of February 27, 1911, carried an item for preliminary examination of the "basin of Winyah Bay, S. C., with a view to providing a uniform depth of 18 feet at mean low water, and to giving increased harbor facilities to the city of Georgetown." The report of examination was published as House Document No. 278, Sixty-second Congress, second session. The improvement desired by local interests contemplated the dredging to a depth of 18 feet of a rectangular basin 2 miles long and threefourths of a mile wide, with the middle of the basin about opposite the mouth of the Sampit River. The report was unfavorable.

6. Previous improvements. In its original condition the bay was connected with the sea by a passage 24 miles long and three-fourths of a mile wide at the gorge. Through this passage were two principal channels, the better of which had from 7 to 10 feet depth over the bar at low tide. There was a 12-foot channel from the bar to the mouth of the Sampit River, 16 miles distant, when the Sampit River Bar again reduced available depth to 9 feet. Due to cross currents and to sediment brought down by the several rivers entering this estuary, the channels within the bay as well as across the bar fluctuated from year to year. Navigation was at all times difficult and uncertain.

Operations for the improvement of navigation in Winyah Bay were begun in December, 1884, under a project to secure a channel 200 feet wide, 12 feet deep, and 2,850 feet long through the Sampit River Bar immediately below Georgetown. The project for this work was adopted by the river and harbor act of August 2, 1882, and was based on survey made in 1880, mentioned above. (Par. 5 (b).) The cost as originally estimated was $14,000, but this was increased at various times up to 1889, when it was placed at $14,500, which amount was eventually appropriated. The increase was occasioned by the fact that the proposed channel traversed a submerged cypress swamp,

which increased the cost of dredging, and also by the inadequate appropriations made from time to time, which were not sufficient to complete the work, and permitted damage to unfinished work and deterioration of plant, as well as increased the cost of superintendence. The project was completed January 10, 1893, at a total cost of $42,146.31, full channel dimensions having been obtained. By the acts of June 6, 1900, and June 13, 1902, this project was virtually merged with that for Winyah Bay, in that legal authority was given to use any dredges employed in connection with the improvement of Winyah Bay for the purpose of dredging shoal places between the outer bar and the city of Georgetown, S. C., including the Sampit River.

In the meantime, the river and harbor act of August 5, 1886, had adopted a project to secure a channel not less than 15 feet deep at mean low water, to be obtained by two jetties springing, respectively, from North and South Island and converging to 4,000 feet at the 18-foot curve on the seaward side of the bar. (See par. 5 (e), ante.) As originally projected the north jetty was to be 10,700 feet, and the south jetty 17,500 feet long. Construction work on the former was actually begun in February, 1890, and work on the south jetty was begun March 15, 1898. The former was completed by June 30, 1903, and was then 11,139 feet long with a crest 4 to 6 feet above mean low water, except that the outer 100 feet were submerged. The south jetty was completed in 1904. It was 21,051 feet long with crest heights varying from 10 feet above mean low water at the inner end to nothing at the outer end. In the meantime, also, an earthen dike had been built along the shore line of South Island, to prevent erosion and changes in the tidal regimen of the bay. The effect of this dike was augmented by "spur jetties" and some post and brush "sand catchers," or groins. This dike really served as the root of the south jetty, and as eventually built was 14,300 feet long. A seagoing suction dredge was also built and placed on the work in September, 1898. Up to June 30, 1912, when the present project had been completed to such an extent as to render unnecessary any further work on the 15-foot project, the expenditures on the latter had amounted to $2,398,351.88 for new work and $123,858.64 for maintenance.

7. Existing project.-The existing project provides for a channel 400 feet wide and 18 feet deep at mean low water from the entrance of Winyah Bay, following the western shore as far as may be necessary to a point on the Sampit River 1 mile above the limit of the city of Georgetown. This channel has been secured and maintained by (a) the construction of two jetties springing, respectively, from North and South Islands, and converging to give an opening 4,000 feet wide at the 18-foot curve on the seaward side of the bar; (b) by dredging across the bar to the 18-foot curve indicated; (c) by construction of an earthen dike 14,300 feet long to protect the shore line of South Island at the southerly side of the bay; (d) by dredging in the bay proper, following the southwestern shore for a distance of about 6 miles opposite Mud Bay; (e) by the construction of a training wall to deflect the current into the concave bend along the western shore, and finally (f) by dredging in Sampit River opposite the city of Georgetown and across the bar at the mouth of the river.

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