178 DOCUMENTARY HISTORY OF THE FLORIDA CANAL

level or a lock canal, and whether it should be 80 or 35 feet in depth. The
data before the Department Indicate rather clearly that the effects of the
sea-level canal on the underground water supply of the State will not be of a
widespread and serious nature. Consequently there is no necessity for the
construction of a lock canal at an increase in construction cost and in oper-
ating time over a sea-level canal The information gathered by the Depart-
ment shows that a depth of 80 feet will suffice for practically all vessels now
engaged In the Gulf trade, or likely to be engaged in that trade for some time
In the future.
 & You refer to paragraph 8 of the resolution which proposes an inquiry into:
 "The sufficiency of authentic information to determine whether the canal will
 contaminate the ground-water supply of the adjacent areas", and ask if, in
 my opinion, a sumciency of information with respect to underground water
 supply has been gathered to make a determination of the effect of the canal
 on such supply. This Department, in its investigations of the canal, has uti-
 lised the services of expert geologists and water engineers. A special board of
 review, formed pursuant to instructions from the President, also had the
 services of a competent water engineer. The preliminary data gathered by
 the Department indicated that there was some possibility of adverse effects on
 the underground water supply. The more detailed information which is now
 available clearly indicates that the adverse effects are largely local and not of
 a serious nature. When the project was placed under way as a part of the
 relief program, I had the district engineer at Ocala, Fla., assemble a board of
 selected experts to consider the data gathered by the two boards, the State
 geological department, and the Geological Survey, and to undertake additional
 and exhaustive field investigations. These experts have recently submitted
 their interim report which definitely concludes that the effects of the sea-level
 canal on the underground water supply will not be serious, but local in nature,
 and capable of control with reasonable expenditures for remedial works. The
 authentic information available permits the conclusion that the sea-level canal
 will not contaminate the underground water supply of adjacent areas.
 4. You refer to paragraph 4 of the resolution which proposes an inquiry
 into: "The nature and extent of the available traffic to warrant the ultimate
 expenditure of between $140,000,000 and $200,000,000", and ask if a sufficient
 investigation and examination has been made and data compiled to enable
 a decision as to the amount of cost of the project which available traffic will
 justify. The special board of engineers had available data compiled by the
 Department of Commerce. In addition, they made a detailed study to deter-
 mine the economic benefits to transportation which would result from the con-
 struction of the canal. While this information and data have not been re-
 viewed in detail by the Board of Engineers for Rivers and Harbors, it is most
 complete and adequate for a full determination of the estimated value of the
 benefits to navigation which will result from its construction.
 5. You refer to my appearance before the subcommittee of the Committee
 on Commerce on January 17, in which certain questions were asked with re-
 spect to the replies received from shipping concerns to a questionnaire sent
 out by the special board of this Department in connection with their investi-
 gation, and ask if these letters were used to establish the economic justifica-
 tion of the project, and further as to the usual factors which are studied in
 determining economic justification. This Department has not stated that the
 replies to these questionnaires represented the economic justification for the
 canal project, nor are such letters generally used for the establishment of
 economic Justification. The special board of Army engineers made an extensive
 economic survey, and was aided in the preparation of its report by an inde-
 pendent survey undertaken by the Department of Commerce at the request
 of the Chief of Engineers. The determinations of the special board with re-
 spect to the economic benefits of the project were based in large part on these
 surveys. The letters to which you refer are some of the replies to question-
 naires addressed by the special board to shipping concerns, so that it might
 be informed as to their opinions with respect to the effect of the project on
 the Individual Interests of the companies concerned. In determining the eco-
 nomic justification of a proposed river and harbor improvement, the investi-
 gating officers ascertain the definite savings in time and distance which will
 be made available to navigation without increased hazards as a result of the
 improvement in question. These savings in time and distance converted into
monetary savings and such other incidental benefits as clearly accrue to water-