John E. Frey

An Instance Of Thermal Pollution And The Effect On Temperature And Oxygen Levels In A Middle Georgia Reservoir

Limnological data collected during a four and one-half year period at Lake Sinclair is reviewed. Comparison of temperature and oxygen profiles are made in areas of the lake receiving hot water discharge and in unaffected areas. Hot water discharge was found to increase temperature and dissolved oxygen substantially during both summer and winter. In addition, hot effluent eliminated or altered the thermocline in the affected area. These effects were evident in varying degrees for 2.3 miles below the source. Observations concerning the sport fishery within the area receiving hot water...


The Effects Of Cold Water Discharge On A Downstream Reservoir's Temperature And Oxygen Levels

Data are presented on the effects cold water discharge from Hartwell Dam has on a twenty-mile stretch of river between Hartwell and Clark Hill Reservoirs and its influence on the temperature and oxygen concentrations beneath the thermocline in the lower lake. This study revealed that oxygen concentration increased from 0.7 ppm to between 3.2 and 6.7 ppm when the sub-60 degree F. water was taken from a 105-foot depth in Hartwell Lake and discharged into the tailrace during generation periods. This water further increased its oxygen content as it became agitated while moving over shoal...


Field Evaluations of Newer Aquatic Herbicides

The results of 116 aquatic weed control experiments using 10 herbicides and their combination are discussed. Included are data for pre-emergent soil application during winter draw-down, pre-emergent total pond treatments and post-emergent applications. Pre-emergent soil application during winter drawdown was comprised of 31 experiments, testing varying concentrations of eight different soil sterilants for the control of rooted aquatic weeds. D.M.A. (disodium monomethylarsonate) showed promise as a pre-emergent control of southern watergrass (Hydrochloa carolinensis). Also,...