Hydrology and Water Quality Modeling

Puneet Srivastava, Latif Kalin, Suresh Sharma, and Rewati Niraula

Discovering sources of pollution in the Tallapoosa River watershed and developing models that can predict future water quality and quantity problems is the focus of the Tallapoosa Watershed Project Hydrology and Water Quality Sub-project research team.  

Saugahatchee Creek embayment and its tributary, Pepperell Branch—both of which are part of the Tallapoosa watershed—are currently on Alabama’s 303(d) list of impaired waters due to such problems as excessive nutrients, organic enrichment, and reduced dissolved oxygen levels. Knowing the sources of the pollutants that are contributing to these problems will help regulatory and conservation agencies and other stakeholders find economically viable ways to clean up and protect the basin’s water supply.  And that information can be used in conjunction with other data to create models that predict how future changes in land use may affect water quality and quantity.

The research team is collecting information from a variety of sources, including data generated by other TWP researchers, to use in the development of hydrologic and water quality models for the Saugahatchee watershed.  These models can be calibrated to accurately predict future responses of the watershed to land use and land cover changes and to help stakeholders develop and adopt mitigation measures.

The researchers are plugging this local data into SWAT (Soil Water Assessment Tool; a hydrology/water quality model used to predict long-term impacts of management and agricultural practices on a watershed) and GWLF (Generalized Watershed Loading Functions; a model that simulates mixed land use watersheds to evaluate the effect of land uses on sediment and nutrient loads in streams) models.  Using such information as past and current land use, water flow, point and non-point pollution sources, and weather data, these models can be specifically designed to predict future problems and potential “hot spots” in the watershed.

Once the models are fully developed, they can be applied to various land use scenarios and, ultimately, may help identify optimal best management practices for the watershed.