FLORIDA GEOLOGICAL SURVEY


 A levee now fills a saddle in the drainage divide between Green
Swamp Run and the Withlacoochee River in northeastern Polk
County south of the Polk-Lake County line (fig. 5). Prior to the
construction of the levee (about 1956 or 1957), drainage from Green
Swamp Run divided into flow westward into the Little Creek basin
(now the Withlacoochee River basin) and flow northward into Big
Creek basin.
 Lake Lowery and swamps in the upper Withlacoochee River
basin are connected by a natural saddle (C-1) in the confining ridge
northwest of the lake. This saddle is 200 to 300 feet wide and is
one point at which flow may be diverted between the Palatlakaha
Creek and Withlacoochee River basins. At high stages the two
basins are interconnected at this point. Apparently water may flow
through this saddle in either direction, depending on the
distribution of rainfall and the relative water levels in the basins.
 There are four interconnections (C-2) between Big and Little
creeks. These openings, all in Lake County, are small and their
net exchange of water is probably negligible in comparison with the
total flow from the basin.
 Other places, shown on the map in figure 5, where basins are
interconnected are: (C-4) between the Withlacoochee River
headwaters and Peace River headwaters; (C-5, C-6, C-7) between
Lake Mattie, Withlacoochee River, and Pony Creek; and (C-8)
between the Withlacoochee River and Devils Creek. Many of these
interconnections act as equalizing channels through which water
may flow in either direction, depending on relative water levels in
connected basins.

 EFFECTS OF MAN-MADE CHANGES

 Many of the physical changes that have been made on the land
 surface through man's efforts have already been described. The
 most extensive developments of the area have occurred in recent
 years, but the first changes in the hydrologic characteristics
 undoubtedly occurred several years ago when logging trails and
 tramroads were built and much of the native timber was cleared
 from the area. The early developments of the area cannot be
 evaluated as they predate the period of data collection, but they
 probably had only minor effects on the hydrology.
 Changes in the drainage characteristics of the Green Swamp
 area can be detected by comparing the hydrologic data for years
 before drainage developments with the data collected since major