DOCUMENTARY HISTORY OF THE FLORIDA CANAL


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the rainfall Ultimately this water finds its way to the wells at Jacksonville,
Sanford, Orlando, Sarasota, and many other Florida cities.
 This conclusion is supported by the reports of the Florida State Geological
Survey. Typical of these is its report-rn ground-water investigations in Orange
County, published in 198& In this county the Ocala limestone, described as the
"chief water-bearing formation of the area", is but 100 to 150 feet beneath the
surface. As for where the water comes from to replenish that taken up by
the wells, V. T. Stringfield, of the United States Geological Survey, who wrote
this report, has this to say:
 "Natural recharge of the Ocala limestone occurs where the formation crop
out northwest of Orlando, in Sumter and Marion Counties, and also locally
through sinkholes that have open underground outlets and the drainage wells.
It seems likely that only a comparatively small amount of surface water reaches
the Ocala limestone locally except through the sinkholes and drainage wells,
because the Hawthorn formation, which overlies the Ocala limestone, contains
impervious members that probably prevent the water from passing downward."
 Other State reports on the Ocala limestone water supply in Sarasota, Hills-
 borough, Seminole, and Duval Counties contains the same conclusion-that local
 recharge is comparatively small and that most of the water comes from that
 part of the State where this rock formation reaches the surface.
 Considering the very porus nature of the Ocala limestone, and the importance
 of the catchment area in Citrus, Sumter, and Marion Counties to the water
 supply of Florida, it is inconceivable that anyone should even consider building
 a salt-water canal through this part of the State. The route for it cuts through
 the very heart of the Ocala limestone. For a distance of at least 35 miles,
 from Yankeetown to Dunnellon, and east of there, the cut would be through
 almost pure limestone. And it would be no ordinary ditch, for this canal is to
 be not less than 250 feet wide at the bottom and not less than 30 feet below
 sea level, which means that its bottom in places will be from 100 to 150 feet
 below ground level-a pretty far reach for those of us who may have to resort
 to fishing from its banks to earn our living.
 What will happen to Florida's water supply when the salt water of the Gulf
 is carried through the Ocala limestone by this canal? There is good authority
 for the belief that eventually this saline water will permeate the entire distance
 of the canal Fresh waters draining into it could not hold back the tides from
 the Gulf and Atlantic. There is nothing to prevent the ready entrance of sea
 water into the Ocala limestone from the canal Paynes Prairie, near the route
 of the canal, once a navigable lake 20 miles square, offers an illustration of how
 quickly large bodies of surface waters can be carried off through this rock
 formation. Salt water seeping into the Ocala limestone from the canal would
 contaminate its fresh water for an indeterminable distance. This impurity
 would become progressively worse with time. It is impossible to predict how
 rapid this change in the character of water would develop, but geologists who
 have studied the problem mince no words in warning that there is great poten-
 tial danger in polluting the fresh waters of the Ocala limestone in the con-
 struction of the sea-level canal. It is conceivable that in time the salt water
 might reach the lower depths of the Ocala limestone many miles away.
 Fresh-water tables for miles back from the route of the canal will be materi-
 ally lowered, for in places the excavation will be 50 feet below the present
 fresh-water table. This canal will be a gigantic drainage ditch for some of the
 most productive agricultural counties of central Florida. The damaging effect
 which many drainage districts have had on agricultural-land values will be
 insignificant in comparison with the loss in the productivity of Marion and
 Sumter County farming lands when their water tables drop to lower levels.
 Also worthy of consideration is the extent to which this drainage of surface
 waters will increase the cold-weather hazard.
 The lowering of fresh-water tables in this area where the Ocala limestone
 comes to the surface might have serious, if not disastrous, results for the
 farmers in Seminole, Sarasota, and other counties where there has been some
 encroachment of salt water in wells tapping the Ocala limestone. Some of the
 pressure which keeps salt water below the depth of artesian wells in these
 counties, and which forces fresh water to the surface for irrigating crops, comes
 from the elevation of water-table levels in the upper part of the Ocala lime-
 stone, near Ocala and Dunnellon.
 Salt water weighs 1026 times more than fresh water, which means, theo-
 retically, that 20 feet of fresh-water head above sea level will depress sea water
 1,000 feet below sea level. In other words, for every foot of fall in ground-