Environmental Impacts of a Desalination Facility Proposed for Tampa, Florida
Alan F. Blumberg, Sean O’Neil and B. Nicholas Kim
The environmental effects of a waste brine plume from a proposed water desalination facility located at Tampa Bay, Florida are addressed through an analysis based on sophisticated three-dimensional hydrodynamic models. The study was separated into two parts: the first part established a base set of physical characteristics such as circulation patterns, temperature and salinity which were corroborated with an extensive set of water quality data; then a design scenario was constructed which included an addition of a desalination facility waste brine plume. The waste brine is mixed with an existing temperature-elevated discharge resulting from a power plant cooling water operation. The first part of the study calibrates and validates the model and provides a base for comparison, while the second part allows for the examination of the differences of the physical variables with and without the waste brine stream. Each scenario was run for a two-year simulation period which provided detailed set of time series and statistics of the temperature, salinity and dissolved oxygen saturation as well as their differences between the two scenarios. Analyses of the results indicates that the only region where any detectable change due to the desalination facility operation is in the immediate vicinity of the waste brine outfall itself. Long-term effects of an elevated salinity plume on the overall salinity in Tampa Bay were addressed by running the model for an additional seven years to achieve steady state. An examination of the model results revealed no significant increase in salinity or temperature. The modeling and data analyses presented herein are quite specific to the Tampa Bay setting; however, the model itself is physically comprehensive and the data quality control procedures are robust. Both are easily adapted to other regions and new sets of observations.