Assessment of the Relationship Between Freshwater Inflow and Biological Indicators in Lavaca Bay

This project will provide an understanding of the relationships between freshwater inflow and habitat in Lavaca Bay based on long‐term monitoring data. It will also provide additional information for consideration by the Basin and Bay Area Stakeholder Committee and the Texas Commission on Environmental Quality during future rulemaking related to environmental flow standards for Lavaca Bay.

The Lavaca River drains into Lavaca Bay, which is a secondary bay of the Lavaca‐Colorado Estuary. There are several factors that can obscure the effects of inflow from river to bay alone, for example: the presence of a major industrial outfall from the Formosa Plastics plant directly into the Lavaca River, the mercury superfund site and dredge spoil island off of the Alcoa Aluminum plant in Lavaca Bay, an active fishery that can deplete living marine resources in Lavaca Bay, and long‐term climate change effects that drive salinity, temperature and dissolved oxygen conditions throughout the ecosystem.

Prior studies evaluating the estuarine health of Lavaca Bay have occurred; however, none have included a rigorous and comprehensive analysis of the biological indicators in Lavaca Bay, nor the specific factors that may be important in Lavaca Bay. This project will analyze data series that are at least 15 years long to identify the elements of the environment related to freshwater inflow that support species or a community, an approach pioneered by the Principal Investigator, Dr. Paul Montagna, in many similar peer reviewed studies in the past.