410 DOCUMENTARY HISTORY OF THE FLORIDA CANAL

 known as route 13B, follows the present St. Johns River Channel from its
 mouth to Jacksonville; then, still following the St. Johns, proceeds south to
 Palatka, 80 miles from the mouth. At Palatka the route turns southwest to
 the Oklawaha River and follows along its valley to a point about 8 miles south-
 east of Ocala, near the famous Silver Springs. Here it turns westward and
 cuts through the high ground of Florida's central ridge, to enter the valley of
 the Withlacoochee River near the town of Dunnellon. From Dunnellon the
 route follows the Withlacoochee Valley in a westward direction to enter the Gulf
 of Mexico near Port Inglis, or Yankeetown, about 80 miles north of Tampa.
 This is the route followed by the present project.
 With the assistance of the United States Coast and Geodetic Survey, which
 established a net of triangulation stations and a line of primary levels within
 a 15-mile strip centered on the preliminary location of the selected route, and
 by utilizing large-scale single-lens aerial photographs and controlled mosaics, an
 accurate alinement was staked out on the ground and a line of levels run
 along it.
 Subsurface explorations were carried out on the alinement. Core drillings
 were made at 1-mile intervals throughout the limestone area and were supple-
 mented, where practicable, by wash boring and churn drill operations. In the
 summit section the casings were left in the core drill holes to permit the periodic
 measurement of the permanent ground water levels. Some 400 wells, sinks,
 lakes, and drill holes were measured at regular intervals over a period of about
 16 months, and pumping tests at a number of sites showed the rate of infiltra-
 tion and exflltration. Other examinations included grouting experiments to
 determine the practicability of sealing cavities in the limestone; field and lab-
 oratory tests to ascertain the bearing capacity of Ocala lime rock; determina-
 tion of the suitability of sand and concrete aggregate; studies of all available
 meteorological, rainfall, and run-off data; accurate determination of the character
 and positions of materials of excavation and the recording thereof on a large-
 scale geological section along the center line of the alinement; and preparation
 of detailed estimates of excavation. Other items of cost also were carefully
 considered.
 To ascertain the economic desirability of the project, the special board made
 extensive studies of the commercial aspects of the areas which would be most
 affected by construction of the canal. Aiding in the compilation of basic data
 in this connection were the Bureau of Research of the United States Shipping
 Board, and the Bureau of Foreign and Domestic Commerce of the Department
 of Commerce.
 The economic studies covered the commercial, Industrial, and agricultural
 development of Florida; a survey of potential local commerce and of the ter-
 minal and transfer facilities of Florida ports; a survey of the Gulf water-borne
 commerce for the calendar year 1981, which disclosed that practically all of
 the Gulf trade would be affected to some extent by the canal and that, there-
 fore, the entire world might be considered as the project's tributary area; an
 analysis of the arrivals and departures- of all ships at United States Gulf
 ports during 1981, which showed that there were 9,573 movements of vessels
 of all types and carrying a total of 41,91,307 long tons, that could have used
 the canal to advantage in making their regular ports of call; and a study of
 the cost of operating ships at sea for each of the several types engaged in
 the Gulf trade.
 The last-named data, that of ships' operating costs, were used to evaluate
 the potential annual savings to vessels transiting the canal, by establishing the
 average saving in operating costs and fxed charges per transit, adding esti-
 mates for saving of interest on cargo and relief from delay due to hurricanes,
 and deducting an expense for pilotage, thus deriving a net saving per transit.
 At the request of the Chief of Engineers, in May 1982, the Transportation
 Division of the Bureau of Foreign and Domestic Commerce, Department of
 Commerce, undertook an independent economic survey which substantiated the
 findings of the special board. The Division also made an extensive commodity
 study which Indicated trends in the production and distribution of commodities
 in the Gulf area.
 During the following year, the Ship Canal Authority of the State of Florida,
which had been created by an act of the Florida State Legislature, applied
to the Federal Emergency Administration of Public Works for a loan to be
employed In construction of the canal as a local enterprise. Engineers of the
Administration concurred in the selection of the route 13B which the special
board had designated as being the most practical alinement from both engi-