Was a TMDL for copper, ambient toxicity, temperature and sediment toxicity in Patrick Bayou necessary ?
Dorn, Philip*,1, 1 Shell Global Solutions (US), Inc., Houston, TX, USA ABSTRACT- A Total Maximum Daily Loading (TMDL) study of Patrick Bayou for dissolved copper, ambient toxicity, sediment toxicity and temperature is complete. The designated use for the bayou is for navigation and industrial water supply, and not for the protection of aquatic life which was considered as an afterthought for the downstream waters of the Houston/ Galveston Bay system. Extensive field data shows that the bayou should not be listed for dissolved copper and water toxicity. Copper concentrations have not exceeded the new water effect ratio (WER) for the Houston Ship Channel. Chronic ambient toxicity was not observed and past occurrences were attributed to ionic imbalance in two effluents and ammonia related to municipal plant operations. Bayou conditions have been changed with industrial process changes and wastewater system upgrades. Sediment toxicity was inconsistent between species, station location and
