5. Since the shipment of phosphate rock began from this harbor in 1911, there has been a large increase in commerce, and it appears that the maximum has probably not yet been reached. When the existing project was under consideration it was found that a depth of 24 feet would accommodate the class of vessels desiring to use the port. Since that time phosphate-carrying vessels have increased in size, and it is now apparent that a depth of about 27 feet is necessary. In this connection it may be stated that Tampa, also a phosphate-shipping port, has a project depth of 27 feet. Charlotte Harbor is about 90 miles south of Tampa and therefore its use would save a vessel trip of about 180 miles, an important item at present high rates of transportation. Up to the present time this harbor has had the unusual advantage of requiring no expenditure for maintenance. Whether this condition will still obtain with the deeper channel desired can not be definitely determined, but the district engineer is of opinion that it will, and his views appear to be justified. In view of these facts the board concurs with the district and division engineers in believing that it is advisable for the United States to undertake the further improvement of this harbor to the extent proposed. When the existing project was adopted in 1912, the traffic was largely in the hands of one company, and the future development of the port was more or less problematical. It was therefore deemed equitable to require liberal local cooperation in carrying out the work. The harbor has now become an important phosphate port, however, and is used by a number of interests. The work contemplated is at thẹ ocean entrance through Boca Grande, and in the opinion of the board it is proper for the United States to undertake this improvement without further cooperation on the part of local interests. The board therefore expresses the opinion that it is advisable for the United States to undertake the further improvement of Charlotte Harbor, with a view to securing a channel 27 feet deep, as proposed by the district engineer, at an estimated cost of $100,000. The full amount of the estimate should be made available in one appropriation.

6. In compliance with law, the board reports that there are no questions of terminal facilities, water power, or other subjects so related to the project proposed that they may be coordinated therewith to lessen the cost and compensate the Government for expenditures made in the interests of navigation. For the board:

To: The Chief of Engineers, United States Army.

(Through the Division Engineer).

Subject: Preliminary examination of Charlotte Harbor, Fla.

1. In compliance with instructions in letter of September 1, 1917, report is submitted of a preliminary examination of Charlotte Harbor,

Fla., authorized by the item of the river and harbor act approved August 8, 1917, reading as follows:

The Secretary of War is hereby authorized and directed to cause preliminary examination and surveys to be made at the following-named localities:

2. Charlotte Harbor, Fla., is a large bay on the west coast of Florida, 70 miles south of Tampa Bay. Its entrance is through Boca Grande Pass. Within the main entrance is Charlotte Harbor proper, which may be considered to extend from Gasparilla Island to Punta Gorda. Charlotte Harbor is one of the best natural harbors on the west coast of Florida. The original channel depth through Boca Grande Pass was about 19 feet. The present channel at Boca Grande has 24 feet at mean low water and a width of channel of 300 feet. After passing through the improved channel at Boca Grande, there exists a wide expanse or anchorage basin, covering about 350 acres and having a depth of 24 feet at mean low water. Of the 350 acres, about 250 acres have 27 feet or more and an average depth of 30 feet up to the dock at South Boca Grande, constructed by the Charlotte Harbor & Northern Railway Co. Charlotte Harbor is about 5 miles in width, having two equal arms extending eastward for a distance of 11 miles and northward for 11 miles. Punta Gorda is at the head of this bay on Peace River, which empties into Charlotte Harbor at its northern extremity.

3. The following table gives reference to previous reports on the improvement of Charlotte Harbor, Boca Grande, and Peace River:

of House"..

181 58th..... 2d.....

1904

1714 Unfavorable.

1 60th.. 699 62d. 121 63d.

1st.
2d..

1st.

Do. Favorable. Unfavorable.

Survey of Charlotte Harbor and

Peace Creek, Fla.

Preliminary examination

Boca Grande and Charlotte
Harbor, Fla.

Preliminary examination of House...
Charlotte Harbor, Fla. (12-
foot channel extension).

Review by Board of Engineers.. Comm..
Survey of Charlotte Harbor, Fla. House..
Preliminary examination of ...do?.
Charlotte Harbor, Fla.

! Favorable only for dredging in Charlotte Harbor at an estimated cost of $30,000.
With map.

Favorable to 23 feet over the bar at an estimated cost of $35,000.

Favorable to 25 feet over the bar at an estimated cost of $140,000.

Favorable to 24 feet over the bar at an estimated cost of $40,000, provided local interests contribute onehalf of the original cost.

4. Before improvement by the National Government Boca Grande Pass had a natural depth of 19 feet or more available at low water and on July 25, 1912, Congress adopted a project to secure an available channel depth of 24 feet and width of 300 feet from the gulf to Boca Grande. This project was completed in 1913, and has maintained itself without expense, and there now exists a channel of 24 feet depth having a width of 300 feet from the Gulf of Mexico through Boca Grande Pass to the wharves at South Boca Grande. Before the Atlantic Coast Line Railroad was built to Punta Gorda boats drawing 6 feet of water operated regularly between Cedar Keys, at that time the southern terminus of the Florida Central & Peninsula Railway, now the Seaboard Air Line Railway, and docked at Punta Gorda, near the mouth of Peace River. In 1900 the National Government completed work which provided a channel 12 feet deep and 200 feet wide from Boca Grande to Punta Gorda. There are no bridges spanning the Boca Grande Pass or the waterway from Boca Grande Pass to Punta Gorda.

5. The field work on this preliminary examination was conducted by Mr. W. W. Fineren, junior engineer, and he states as follows in regard to the desired improvement:

The Charlotte Harbor & Northern Railway Co. and all phosphate companies who ship by that route desire a channel 30 feet deep over the bar at mean low water, so that at all times an available depth of 27 feet will be secured. The Pilots' Association desire that the inner end of the channel be widened and "eased off,” so that the larger boats can make the turn with less difficulty and danger of going on the shoal at the breakers.

The 24-foot channel over the bar is holding its own, and has not shoaled any since dredging. Immediately inside of the bar channel there is from 24 to 40 feet of water in the natural channel with ample anchorage inside of the harbor, and deep water up to the terminal dock. The mean rise and fall of the tide at the bar is nearly 2 feet, and at Punta Gorda 1.4 feet. There is a tidal current of about 1.5 miles per hour in the harbor. The natural channel leads out from the pass considerably south of west, and then turns somewhat abruptly into the dredged channel leading considerably west of south. The entrance to the dredged channel is within 1,000 feet of the breakers to the north of the channel, and the fact that the bend in the channel occurs at that point causes pilots of large steamers to fear the breakers. It can not be said, however, that the channel is difficult to navigate, although a change of direction of the inner end of the dredged cut would be advantageous to navigation. At times of high northeast winds the tide goes nearly 3 feet lower than ordinary low water, and the main channel depth is decreased by that amount. On December 11, 1917, the tide all along the coast went 3 feet lower than usual, and a large steamer, drawing 22 feet 6 inches was delayed over six hours before the tide rose sufficiently to permit her to depart. At such times the 24-foot depth is not available.

The Charlotte Harbor & Northern Railway, in letter to this office of October 11, 1917, states as follows in regard to the desired improve

ment:

We are, from a great many viewpoints, interested in this project, and in addition to our own benefit-we are very greatly interested in the territory served by our railroad-it in turn would be benefited by this proposed project.

There are about 350,000 to 400,000 tons of phosphate handled through this port annually, which will undoubtedly be very greatly increased after the war, which, of course, increases the necessity of improved channel conditions. There is other freight such as lumber, ties, and naval stores that could be handled through this port.

The principal interest in the improvement of the present channel through Boca Grande Pass is manifested by the Charlotte Harbor & Northern Railway Co. This channel is used nearly exclusively for business originating on the Charlotte Harbor & Northern Railway, the terminus of which is South Boca Grande, a town having a popula

tion of about 500. In the early reports on the improvement of Boca Grande Pass statistics were introduced to show that with the pass improved there might be some shipment of fruit and vegetables to the central west by boats via Mobile and New Orleans. This business has not developed and the improvement of this channel must rest principally upon the necessity of providing a deeper channel for boats engaged in handling phosphate, the phosphate being brought by the Charlotte Harbor & Northern Railway to South Boca Grande. It is not thought necessary that the channel to fill the requirements of navigation should be increased beyond the width now existing. The improvement to a depth of 30 feet, so as to provide available depth of 27 feet at all stages of the tide, may be considered as complying with the request.

6. Boats using Boca Grande Pass during the year 1917 covered a total of 142 trips, counting arrival and departure as one trip. Of these steamers 100 were American and 12 foreign. There are no regular lines entering or leaving the port except so far as certain boats make repeated calls at this port for the purpose of securing cargoes of phosphate and lumber.

7. Commerce passing through Boca Grande Pass is as follows:

The above includes both arrivals and departures. In addition a local steamer made about a dozen trips in and out of the harbor.

NOTE. This tonnage is about 14 per cent under that of 1916, due entirely to shortage of vessels.

70,000

1,438,640

At the beginning of the present war phosphate shipments at South Boca Grande terminals had reached nearly 500,000 tons per year, which greatly exceeded tonnage that was thought probable if the channel was improved to the 24 feet depth. The war has interfered seriously with the shipment of phosphates from the State of Florida to foreign markets, but it is anticipated that at the conclusion of the war there will be an increased demand for phosphates and that the shipment from South Boca Grande will be much greater than ever before. Phosphate is shipped from South Boca Grande in the dry state. From the dry phosphate phosphoric acid is extracted, and this in turn is used in the preparation of fertilizer. The demand for phosphoric acid as a fertilizer will be very great after the war, as the farming lands will require additional fertilizer, the use of fertilizer having been much restricted by the inability of the warring countries to secure it.

The following companies, etc., are interested in the improvement of Boca Grande Pass:

The Charlotte Harbor & Northern Railway Co., Arcadia, Fla.

The Export Phosphate Co., Bartow, Fla.

The American Agricultural & Chemical Co., Pierce, Fla.

The Prairie Pebble Phosphate Co., Mulberry, Fla.

The Boca Grande Pilots' Association, South Boca Grande, Fla.

8. In regard to the work required to give a channel 27 feet deep and 300 feet wide through Boca Grande Pass, excavation will be required for about 2 feet for a distance of about 9,000 feet. Previous surveys taken at this locality have shown that no rock will be encountered to a depth of 30 feet. A recent survey made of the locality indicated that the 24-foot depth of channel with width of 300 feet, as completed under present project, has shoaled but little.

9. There are forwarded herewith two letters received from the Charlotte Harbor & Northern Railway expressing the desire of that company for the improvement of the channel. No other communications have been received.

10. In regard to terminal facilities the following extract is taken from the report of Mr. W. W. Fineren, junior engineer:

At South Boca Grande the C. H. & N. Ry. has installed the finest loading apparatus for phosphate that can be found in the State. This consists of a storage shed containing 23,000 tons of phosphate when filled. A belt conveyor runs from the hopper into which the cars dump through the storage shed and out to the end of the loading dock, 80 that the phosphate can be dumped into the shed or the boat at will, and when a supply is not coming from the cars it can be drawn, without interruption, from the storage supply in the shed. Under this arrangement a maximum of 600 tons per hour can be loaded into a vessel, but counting all incidental delays due to various causes an average of 400 tons per hour is usually reached and boats loaded in from six to eight hours with all that they can carry over the bar drawing 24 feet. It is possible for a large steamer of 3,000 tons capacity to enter the harbor, load and clear within 12 hours, which is a factor of extreme importance in shipping.

11. There are no questions of water power, drainage, reclamation, or flood protection involved in the improvement of the proposed channel.

12. There is forwarded herewith a map of "Preliminary Examination, Charlotte Harbor, Florida," one sheet, dated January 11, 1918. 13. In the Board of Engineers' report of January 3, 1912, on the improvement of this waterway, it was stated:

At the present time only one phosphate company is shipping through Boca Grande, but the output of this company is at the rate of about 300,000 tons per year, and it appears that contracts with other companies have been made which will amount to at least 200,000 per year. The depth available through the entrance is now about 19 feet, and it appears that the depth of 24 feet is required to meet the need of the character of vessels engaged in the commerce of the port.

The phosphate shipments from this port at the beginning of the present war had reached 500,000 tons or more per year. There are numerous deposits of phosphates along the line of the Charlotte Harbor & Northern Railway, and at the conclusion of the war it is thought that the shipments out of this port will be greatly increased over those existing previous to the war. The Board of Engineers' report of 1912 stated that

Depth of 24 feet is required to meet the needs of the character of vessels engaged in the commerce of the port.

1 One printed.