DOCUMENTARY HISTORY OF THE FLORIDA CANAL 93

ments of the summit section at elevation plus 40, and that adjacent water
supplies and ground under cultivation would not be harmfully affected.
 The examiner concludes that this project is technically sound..
(From p. 6.)
 Traffic and revenue.-Our estimate of potential traffic available for the pro-
posed trans-Florida canal is based on traffic reports of the year 1981 of the
actual ship records of ships entering and departing from the United States
Gulf ports to all Atlantic ports north of thirtieth parallel of latitude. We have
considered only direct commercial seagoing ships in our estimates. The rec-
ords of other types of craft are not available and while such traffic would
doubtless add somewhat to the total potential revenue, the lack of records as
to such ship and barge movement makes it impractical to consider it here.
From our studies of the charts presented with the report of the United States
Engineer Corps, it appears that the saving in time of vessel movement
originating in the Mexican Gulf ports to be so small that it would not prove
economical for such traffic to use the canal. We have, therefore, not considered
any traffic originating in Mexican Gulf ports as potential traffic.
 As stated in the report of the United States Engineer Corps, the ship move-
ment of 1981 is probably representative of the normal traffic as to number of
potential transits. But, due to the business depression, the amount and value
of the cargoes is below normal. The total number of potential transits during
1931 was 9,996, and the total number during 1929 was 10,41. The assumption
of 10,000 transits is reasonable, and it is upon this number of transit that the
revenues projected are based.
(From p. 11.)
 The total estimated cargo tonnage that would have passed through the canal
 in 1932 was 40,338,000 tons, and the total revenue derived was $8,100,000, or
 approximately 21 cents per ton of cargo. Therefore, the increase in revenue
 on account of potential barge traffic can be estimated at $404,000. Allowing
 this increase, the total revenue to be anticipated is $8,524,000.
 (From p. 14.)
 The average total annual maintenance cost used by the examiner is
 $2,109,000.
 (From p. 15.)
 In the following tables the annual revenue used is 80 percent of the estimated
 possible revenue from tonnage available, that is, 80 percent of $8,120,000, of
 approximately $6,500,000. It is considered that this return can be realized
 as the potential ship traffic only has been considered. The margin above this
 estimate revenue may be summaried as follows:
 (1) 20 percent of $8,120,000, or--------.-------.------.--- $1, 620, 000
 (2) Barge traffic .---... ----------------------- 404,000
 (3) Time saving to shipping interests--- -- _--..
 (4) Pleasure-craft revenue-...---- ---.............._
 (5) Stimulation factor- -------------------1,600,000
 (6) Credit to Federal Government for use of canal as link in inland
 waterway system --------- - -----_
 Total-------------- -- ----- ------- 3, 624, 000
 Item (3) is a real factor, the value of which, although an appreciable item,
 does not admit of any precise determination.
 Item (4) should be considered but as no definite analysis can be made it
 is neglected.
 Item (5).--This item is from the report of the United States Engineer Corps.
 Item (6).-This item, estimated at $1,000,000 annually by the United States
 engineers, is not considered as it is, in part, offset if item (2) is considered.
 A conservative increase in traffic, accompanied by equivalent increases in
 maintenance and operation costs, has been used in following amortization tables
 as noted thereon.
 The economic soundness of this project, the examiner believes, is demon-
 strated in a reasonable and conservative manner.