Nutrient and Sediment Variability in the Lower San Jacinto River

Science Center Objects

The San Jacinto River is the second largest inflow into Galveston Bay. The USGS Texas Water Science Center collects water-quality samples in the lower reaches of the San Jacinto River over a range of hydrologic conditions to improve our understanding of the variability of nutrient and sediment concentrations in freshwater inflows from the San Jacinto River into Galveston Bay. 

Previous research conducted by the U.S. Geological Survey in the Trinity River, the main freshwater inflow to Galveston Bay, characterized and quantified freshwater volume, suspended sediment, and nutrients entering the estuary from the lower reaches of the Trinity River. The findings from this study improved the understanding of the processes driving the delivery of nutrients and sediment in freshwater inflow from the Trinity River to Galveston Bay; however, the Trinity River only provides a portion of freshwater inflows into Galveston Bay.  

The San Jacinto River is the second largest inflow into Galveston Bay.  Similar research on this large source of freshwater inflow to Galveston Bay will help scientists and water managers better understand nutrient and sediment delivery into the estuary.

In this project, USGS Texas Water Science Center scientists:

  • Measure streamflow in the lower reaches of the Trinity River at various hydrologic conditions to establish the potential of installing an index-velocity streamflow station in the lower reaches of the San Jacinto River;
     
  • Collect water-quality samples in the lower reaches of the San Jacinto River over a range of hydrologic conditions to better understand the variability of nutrient and sediment concentrations in freshwater inflows from the San Jacinto River into Galveston Bay; and
     
  • Evaluate the potential for developing continuous regression models based on surrogate parameters, such as acoustic backscatter and water-quality properties, to estimate nutrient and sediment concentrations at 15-minute intervals in the San Jacinto River.