REPORT OF THE BOARD OF ENGINEERS FOR RIVERS AND HARBORS PETERSBURG HARBOR, FLA., WITH ILLUSTRATION HERETOFORE SUBMITTED ON ST. Div. Hon. J. J. MANSFIELD, WAR DEPARTMENT, OFFICE OF THE CHIEF OF ENGINEERS, Chrman Committee on Rivers and Harbors, House of Representatives, Washington, D. C. MY DEAR MR. MANSFIELD: 1. The Committee on Rivers and Hartors of the House of Representatives, by a resolution adopted FebMary 23, 1933, requested the Board of Engineers for Rivers and mitted pursuant to provision in the river and harbor act approved July 3, 1930, with a view to determining the advisability of pro riding a channel of suitable dimensions extending from St. Petersin a southerly direction to the main ship channel in the lower bay at the present time. I enclose herewith the report of the Board In response thereto. burg the 2. St. Petersburg Harbor is on the west side of Tampa Bay, near southerly end of the peninsula separating Tampa and Old Tampa Bays from the Gulf of Mexico. It is 21 miles southwest of the city of Tampa and its port facilities, at the northerly end of Hillsboro Bay, and 9 miles southwest of the terminals designated as Port Tampa on the west side of Interbay Peninsula, which separates Hillsboro and Old Tampa Bays. Under the project for Tampa Harbor the United States has provided a 30-foot channel from the Gulf to Tampa and a branch channel of the same depth leading west and north to Port Tampa. St. Petersburg Harbor is sepa rated from the main Tampa Harbor Channel to the south and east by an extensive shoal area, but on the north side of this shoal a natural channel of ample depth extends westerly frorm the 30-foot Port Tampa branch channel to within 1 mile of the St. Petersburg frontage. The existing project for St. Petersburg Harbor provides for maintaining a channel 19 feet deep and 250 feet wide from natural deep water to a dredged basin at St. Petersburg, and a depth of 21 feet in the basin. Under the provisions of the deficiency act of March 4, 1929, an expenditure of $17,000 was made for dredging a channel 14 feet deep and 200 feet wide from the outer end of the authorized 19-foot entrance channel across the shoal area to the southward. The total Federal cost to June 30, 1934, was $94,000 for new work and $21,000 for maintenance. It is reported that city and private interests have spent over three and one-half million dollars in providing yacht basins, terminals, and other waterfront improvements. The mean range of tide at St. Petersburg is 1.5 feet. The further improvements now desired are a channel 30 feet deep and 300 feet wide from the outer end of the St. Petersburg entrance channel southward across the shoal area to the main Tampa Harbor Channel, with similar dimensions in the entrance channel and in the natural channel thence to the Port Tampa Channel. 3. St. Petersburg has a permanent population of 40,000, and is a popular winter resort. Industrial activities are limited chiefly to those relating to the supply of the local community. The city is served by two railroad lines and by modern highways. Commerce of the harbor has increased from 120,000 tons in 1929 to 203,000 tons in 1934, the latter including 77,000 tons of general ferry traffic and cargoes in transit. 4. The Board of Engineers for Rivers and Harbors, after considering the reports of the district and division engineers and the information presented by local interests at a hearing before the Board, is of the opinion that a channel 20 feet deep across the shoal area south of St. Petersburg is warranted by the prospective benefits to general commerce and navigation. It points out that this improvement will effect a saving in distance of 7 miles for all vessels over 14 feet in draft moving between St. Petersburg and the Gulf, and a saving of 4 miles for many of the vessels trading at Port Tampa. The value of the improvement in reduced operating costs for commercial vessels and those of the local Coast Guard unit is evaluated by the district engineer at $18,000 annually. In addition, the improvement will increase the effectiveness of the Coast Guard unit. Depths greater than the 20 feet proposed would benefit only a small proportion of the vessels trading at Port Tampa. The Board recommends modification of the existing project for St. Petersburg Harbor, Fla., to provide a straight channel 20 feet deep and 200 feet wide from the easterly end of the present entrance channel southward to deep water in Tampa Bay, generally as shown on the accompanying map, at an estimated cost of $123,000 for new work and $1,500 annually for maintenance in addition to that now required. 5. After due consideration of these reports I concur in the views. and recommendations of the Board. Very truly yours, E. M. MARKHAM, Major General, Chief of Engineers. PORT OF THE BOARD OF ENGINEERS FOR RIVERS AND HARBORS WAR DEPARTMENT, BOARD OF ENGINEERS FOR RIVERS AND HARBORS, Sect: St. Petersburg Harbor, Fla. T: The Chief of Engineers, United States Army. 1. This report is in response to the following resolution, adopted Fruary 23, 1933: Belved by the Committee on Rivers and Harbors of the House of Reprepntatives, United States, That the Board of Engineers for Rivers and Harbors cated under section 3 of the River and Harbor Act, approved June 13, 1902, be, Dis hereby, requested to review the reports on St. Petersburg Harbor, Fla., itted pursuant to provision in the River and Harbor Act approved July 3, 27 with a view to determining the advisability of providing a channel of able dimensions extending from St. Petersburg in a southerly direction to De main ship channel in the lower bay at the present time. 2 St. Petersburg Harbor is on the west side of Tampa Bay, near the southerly end of the peninsula separating Tampa and Old Tampa Bays from the Gulf of Mexico. It is 21 miles southwest of the city Tampa and its port facilities and 9 miles southwest of the erminals designated as Port Tampa. Under the project for Tampa Harbor the United States has provided a 30-foot channel from the Half to Tampa, with a branch channel of the same depth leading west north to Port Tampa. St. Petersburg Harbor is separated from main Tampa Harbor Channel to the south and east by an extenshoal area, but ample depths are available in the natural channel ing around the north end of this shoal, from the 30-foot Port Tapa branch channel westward to within 1 mile of the St. Petersrg frontage. The improvement authorized by Congress under the Toject for St. Petersburg Harbor provides for the completion and intenance of improvements undertaken by local interests to prode a channel 250 feet wide and 19 feet deep from that depth in Tampa Bay westward to the basin at the port of St. Petersburg, a stance of 1 mile, and for maintenance of the basin to a depth of 21 t, width of 900 feet, and length of 1,400 to 1,700 feet. The ficiency Act of March 4, 1929, authorized the expenditure of £1000 for dredging a channel 16 feet deep and 200 feet wide from outer end of the 19-foot St. Petersburg Channel southerly across shoal to the main Tampa Harbor Channel. With the funds so rided a channel 14 feet deep was secured. It is reported that channel has not subsequently shoaled. It affords, for vessels less than 14 feet draft, a route between St. Petersburg and the f of Mexico approximately 7 miles shorter than the circuitous te around the north end of the shoal; and similarly shortens the tance between Port Tampa and the Gulf by 4 miles. The total Feral cost to June 30, 1934, was $94,000 for new work and $21,000 maintenance. The mean tidal range at St. Petersburg is 1.5 feet. In addition to original dredging in the project channels, local erests have constructed a second basin, called "Bayboro Harbor " t of the project basin. Bayboro Harbor is 1,360 feet long and to feet in maximum width, with a controlling depth of 9 feet. The total cost to local interests of the construction of Bayboro Harbor and work done in the Federal project channels is reported as $890,000 Other improvements include three yacht basins, a 2,400foot recreation pier, and a municipal airport on the harbor frontage. It is stated that the city has spent a total of $2,672,000 on harbor improvements, and that private interests have spent approximately $1,000,000. 4. St. Petersburg, with 40,000 permanent inhabitants, is primarily a residential and resort community. Agricultural products produced in the immediate vicinity are largely consumed locally; the small surplus is shipped by truck, principally through Tampa and Port Tampa. The area is adequately served by railways and improved highways. The commerce of St. Petersburg Harbor has varied from a maximum of 900,000 tons in 1925, when it consisted chiefly of construction materials received by water because of a shortage of land transportation during the Florida boom, to 120,000 tons in 1929, increasing to 126,000 tons of vessel traffic and 77,000 tons of general ferry traffic and cargoes in transit in 1934. Ninety-five percent of the vessel tonnage for the latter year comprised local and intraport movements of petroleum products, shell, boiler water, construction materials, and miscellaneous commodities carried in towed barges or small motor vessels for which present harbor depths are adequate. The small remainder was handled chiefly by the Bull Line, which makes one call per week at St. Petersburg with a ship 325 feet long and 22 feet in maximum loaded draft. 5. Local interests request that a channel 30 feet deep and 300 feet wide be provided from the present 19-foot entrance channel southward across the shoal to the main Tampa Harbor Channel; that this channel be continued to the northeast to the Port Tampa Channel: and that the same depth and width be provided in the existing east and west 19-foot channel of entry to the St. Petersburg Basin. The dimensions requested conform to those provided throughout most of the channels in Tampa Harbor. Local interests claim that this improvement, by affording shorter distances for deep-draft vessels between the Gulf and St. Petersburg or Port Tampa, would afford transportation economies fully commensurate with the expenditures required, and increase the efficiency of the local Coast Guard unit by permitting its deeper draft vessels to follow the shorter route to the Gulf at all stages of the tide. 6. The district engineer has prepared estimates of the cost of channels of various depths and widths extending from the outer end of the 19-foot entrance channel southward to the main Tampa Harbor Channel. These range from $29,000 for a channel 16 feet deep and 200 feet wide to $1,397,000 for a channel 30 feet deep and 300 feet wide. Estimated annual maintenance costs range from $1,200 to $2,500. The district engineer presents an analysis of the benefits to be anticipated from the desired improvement. As any vessel which could enter St. Petersburg or Port Tampa by way of the new channel, if provided, could also enter by way of the more circuitous main channels, he concludes that the value of the improvement under consideration would be limited to the degree in which it eliminates lost time or hazards. The commerce of St. Petersburg itself is largely carried in barges and small motor vessels, for which present depths are adequate, and the benefits to that commerce would be negligible. The district engineer states, however, that the improvement would afford a saving of approximately 2 hours in running time the Gulf for the larger Coast Guard and naval vessels based at & Petersburg and estimates that provision of a cut-off channel 19 et deep would afford direct savings in operating and maintenance equipment costs to these governmental agencies of $10,000 anLally. Assuming an average vessel speed of 8 miles per hour in ter the main ship channel or the proposed cut-off channel, the provement would save, for the larger vessels, approximately onef hour's running time between Port Tampa and the Gulf. Based : 1934 vessel traffic to and from Port Tampa and assuming operat4 costs of $20, $25, and $30 per hour for ships of the various drafts Folved, the district engineer arrives at a total annual saving of 200 in the cost of operating commercial vessels for a 19-foot th, increased by $3,810 for a 26-foot depth. The further savings ira 30-foot channel would be negligible. In addition, the district queer believes that certain of the larger vessels which now lie at or until daylight before proceeding up the present main Port impa Channel might navigate the straight channel under considerin at night. He considers that proper allowance for the latter al for a probable future increase in the commerce of both St. ersburg and Port Tampa would bring the total annual savings $18,000 for a 19-foot channel and $25,000 for a 26-foot channel, cluding savings to the Navy and Coast Guard. If a depth of 20 t be provided, still further benefits not susceptible of definite aluation would lie in the lessened cost and inconvenience to pasengers from St. Petersburg on the boats of the Peninsular & OcDental Line. These boats now operate to and from Port Tampa, would probably make St. Petersburg a port of call if the above hannel depth were available. Comparing annual carrying charges, cluding maintenance and interest at 4 percent with the estimated rings, the district engineer concludes that either a 19- or 20-foot annel would be fully justified but that the 26- and 30-foot channels Told not. He recommends modification of the existing project for 5. Petersburg Harbor to provide a channel 20 feet deep and 250 feet ride, extending from the entrance channel to water of that depth lower Tampa Bay, as shown on the map accompanying his report, ar estimated cost of $163,000 for new work and $1,500 annually for Laintenance, in addition to that now required. i. The division engineer does not concur in the view that improveTent of the southerly channel to a depth of 20 feet is necessary at time. He points out that vessels of as deep draft as can enter Petersburg Harbor have no difficulty in reaching the present 19Sot entrance channel by the northerly approach and considers that alleged saving in distance and cost of operation anticipated to ult from the improvement is largely visionary and incapable of alization. In his opinion, the savings of time would simply enable sels to reach the dock and tie up somewhat sooner, with no actual ductions in any but fuel costs. Noting that the act providing for the dredging of the present channel contemplated a depth of 16 feet, which has never been obtained, the division engineer considers that further legislative authority should be given definitely adopting the project for a depth of 16 feet and width of 200 feet. He believes that the ensuing benefits would justify the small expenditure required. The division engineer recommends modification of the project for St. Petersburg Harbor to provide definitely for a channel 16 feet deep |