Freshwater Inflow to Galveston Bay



Journal Title

Journal ISSN

Volume Title


McFarlane & Associates


Galveston Bay is the most productive estuary in Texas. The Trinity River provides one-half of the freshwater inflow and nutrients, and a substantial amount of the sediment, which reaches Galveston Bay. The Lake Livingston dam and reseervoir, to date, have not reduced the annual river discharge to Trinity Bay but a slight seasonal shift has reduced flow from January to May while increasing flow from August to December. The frequency and duration of floods, important to the transport of floodplain nutrients, has not diminished. The proposed Wallisville dam and reservoir, near the mouth of the river, will potentially divert as much as 39 percent of river discharge and entrap substantial, but unknown, quantities of sediment and nutrients, leading to higher salinities in Trinity Bay and erosion of the rivermouth delta. Sheet flow of floodwaters across the delta marshes, an important nutrient transport mechanism, will be reduced. It is essential that a comprehensive environmental impact assessment, conducted by an independent third-party, be completed to consider the synergistic and cumulative effects of the several in-progress or proposed development projects which currently threaten the Galveston Bay ecosystem.


25 pages; available for download at the link below.


Trinity River, Trinity Bay, freshwater inflow, environmental impact, nutrient flow, sediment flow, estuarine mixing