52 REPORT OF INVESTIGATIONS NO. 50
Jim Branch
Jim Branch drains 5.8 square miles in the south-central part of Orange County. Altitudes in the basin range from 75 to 85 feet. Figure 20 shows a profile of the bed of Jim Branch.
The maximum flow of Jim Branch near Narcoossee (station 51) has not been determined. A dry stream channel has been observed at station 51.
Water collected from Jim Branch on May 23, 1961, was very soft (9 ppm) and low in mineral content (30 ppm, estimated from its conductivity).
Ajay-East Tohopekaliga Canal
This canal drains approximately 171 square miles, of which 54.5 square miles are in Orange County and 116.5 square miles are in Osceola County.
Altitudes of the drainage area in Orange County range from 60 to 90 feet. The topography is fairly flat and is characterized by swamps in the northern part and by lakes in the southern part.
Periodic measurements of the flow in Ajay-East Tohopekaliga Canal near Narcoossee (station 2) have been made since 1942. The maximum measured discharge was 1,420 cfs in March 1960. A reverse flow of 0.25 cfs was measured in February 1946. The average discharge, based on the relation between drainage area and average discharge at several points on the main stem of the Kissimmee River, is estimated to be about 170 cfs or 1.0 cfs per square mile.
The flow into Orange County from an area of 111 square miles in Osceola County has been measured in Myrtle-Mary Jane Canal near Narcoossee (station 31) since November 1949. The maximum flow into the county via this canal was 990 cfs in September 1960. In September 1956, the flow reversed for 2 days and flowed out of the county at the rate of 17 cfs. The average discharge in this canal for the period of 1950 to 1963 was 109 cfs or 0.98 cfs per square miles. Average annual runoff is 13.6 inches at station 2 and 13.3 inches at station 31. This indicates fairly uniform yield from all parts of the basin. Curve 2 (figure 15) is the estimated flow-duration curve for station 2 and figure 21 is the flow-duration curve for station 31. The flatness of the upper parts of these curves indicates the large amount of storage in the lakes and swamps in this basin.