Study to be conducted July 10-17 in Mississippi Sound
To determine a possible relocation strategy for the Bayou La Batre wastewater treatment diffuser, scientists and engineers from several agencies will begin conducting a hydrographic dye dilution study beginning July 10, 2017. The Alabama Department of Conservation and Natural Resources Marine Resources Division (ADCNR-MRD), the Alabama Department of Public Health (ADPH) and the U.S. Food and Drug Administration (FDA) Shellfish Sanitation Program will simulate the flow and dispersion of wastewater by releasing a dye into the waters of Mississippi Sound and tracking it over time.
Two dye injections are scheduled during the study. Due to weather changes, each injection will have a range of start dates to allow for the best selection of weather conditions. Rhodamine Water Tracing dye will be released from two specific areas of Mississippi Sound. The first injection will have a date range of July 10 through July 14, and the second injection will have a date range of July 14 through July 17.  Both injections will start near low tide in the late evening. Each injection will continue for approximately 12 hours until late morning the following  day. Because of the dye injection, portions of Mississippi Sound, including Portersville Bay and Grand Bay, may turn reddish in color for a brief time. This dye is not harmful to people or the ecosystem.
Information collected during this study will be used by the FDA, ADCNR-MRD, and ADPH to evaluate the impact of potential wastewater discharges on shellfish-growing areas and will help scientists determine where shellfish may be safely harvested.