Number of individuals and injury rates of economically important fish passing through the P.H. Robinson Generating Station.

Abstract

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. High mortality associated with the generating station nearly always was limited to the hot-water months when the least fish were present. The largest catch- per-effort values and lowest injury rates recorded for the revolving-screen station were generally observed in the night samples (2200 hr) and the afternoon screen samples (1500 hr) usually had the lowest catch-per-effort values and highest injury rates. Projections of 12 months of revolving- screen-sampling data indicated that approximately 7,191,785 fish weighing 40,288 kg ( 44.3 tons) were caught on the revolving screens in a year. Although this system was the best observed in Texas, the use of horizontal traveling screens is recommended to guide organisms into a bypass for return directly to Galveston Bay rather than the discharge canal during hot months.