The objectives of this study are: to test the quality of the water passing through the Cedar Bayou Electric Power Station of the Houston Lighting and Power Company by maintaining selected species of marine fishes and crustaceans in a series of ponds, cages and aquaria receiving a continuous supply of water directly from the discharge canal of the power plant; to determine the suitability for phytoplankton of the power station's intake and dicharge canals and Trinity Bay; to investigate the potential benefits associated with thermal effluents in relation to the mariculture of selected marine fishes and crustaceans; to monitor temperature, conductivity and dissolved oxygen of the water wherever organisms were tested; and to determine seasonal variations in species composition, distribution and relative abundance of macrocrustaceans and fish within the cooling lake and observe hydrological parameters.