WATER RESOURCES OF ORANGE COUNTY 45
shows the drainage basins and the surface-water data-collection points in Orange County.
Parts of some of the basins delineated on figure 18 are closed basins that do not contribute direct surface runoff.
The efficiency of a stream in removing surface water from the land is closely related to the average slope of its bed. During the flood of March 1960, rainfall on Jim Creek basin above State Highway 520 (drainage area 22.7 sq mi) and on Boggy Creek basin above the station near Taft (drainage area 83.6 sq mi) was about the same. Even though the contributing area of Boggy Creek is more than three times that of Jim Creek, its peak flow was only 3,680 cfs whereas that of Jim Creek was 3.750 cfs. This anomaly can be explained in part by the reduction of the peak flow on Boggy Creek by storage in lakes and swamps. It is due mostly, however, to the fact that the slope of Boggy Creek (3 feet per mile) is about half that of Jim Creek. Streambed profiles for most of the streams in Orange County are included in this report.
KISSIMMEE RIVER BASIN
Reedy Creek
Reedy Creek drains 49 square miles in the southwest corner of Orange County. The drainage from about 22 square miles of this basin in Lake County flows into Orange County. The drainage area above the gaging station near Vineland (station 54) is 75 square miles.
Land surface altitude in Reedy Creek basin in Orange County ranges from 75 feet above msl at the southern county line to 210 feet at Avalon fire lookout tower. The eastern part of the basin consists of relatively flat swampy terrain interspersed with islands of low relief. The western part consists of rolling hills interspersed with lakes and swamps. The divide between Reedy Creek basin and Bonnet Creek basin to the east is rather indefinite, and there is some interchange of water between basins. Figure 19 shows a profile of the bed of Reedy Creek.
At Reedy Creek near Vineland (station 54, 1 mile south of the county line, the minimum flow observed was less than 0.01 cfs in May 1961. The maximum flow was 1,910 cfs at the peak of the flood in September 1960.
The average flow of Reedy Creek near Vineland is estimated to be 55 cfs or 0.73 cfs per square mile. Average yearly runoff from