The effects of the effluent from an electrical generating station on the phytoplankton of Trinity Bay, Texas.

The number of individuals and injury rates of economically important fish passing through the P.H. Robinson Generating Station (1,465 MW) located on Galveston Bay, Texas was investigated February 1969-February 1970. Water temperature, dissolved-oxygen content, conductivity-salinity, hydrogen ion concentration (pH), and biological samples were taken twice weekly at four trawl (two in intake canal and two in discharge canal) and one revolving- screen stations. Screen collections were made for 25 minutes starting at 0700, 1500, and 2200 hr. High mortality associated with the generating station nearly always was limited to the hot-water months when the least fish were present. Blue crabs and algal mats injured many of the fish impinged on the screens. Mean-catch-per-effort values for intake-canal-trawl tows. Movement of fishes into the discharge canal was restricted upstream by the power plant and prevented downstream by a weir. Many fish were resident in the discharge canal during the cool-water months and they were transient with a few exceptions during the hot-water months. Larger mean-catch values and higher injury rates usually occurred at the discharge-trawl-sampling station located near the plant than at the more distant station.