Modeling Support for Attoyac Bayou Watershed– SELECT (06/16/2011) Jasjeet Kaur Kyna McKee R. Karthikeyan Biological and Agricultural Engineering Lucas Gregory Texas Water Resources Institute Copyright© Biological and Agricultural Engineering Department, Texas A&M University

SELECT Spatially Explicit Load Enrichment Calculation Tool An automated GIS tool to assess bacteria loads using spatial factors Land Use Human and Animal Population Densities Slope of Landscape Soil Types Distance from the Creek Identifies nonpoint sources most likely contributing to E. coli contamination in each “sub-watershed” Helps stakeholders target areas of greatest concern where management solutions should be focused Source: http://www.awag.org/Education/Watershed_diagram.jpg Copyright© Biological and Agricultural Engineering Department, Texas A&M University 2

SELECT Land use/ land cover data updated Watersheds delineated Data layers used in SELECT Land use Hydrography (stream network) Urban areas Watershed boundary County boundary Soils Wastewater treatment facilities Census Population density Grazing Cattle Feral Hogs Wildlife Poultry OSSFs Copyright© Biological and Agricultural Engineering Department, Texas A&M University 3

SELECT Model Input Data Census Blocks (U.S. Census Bureau) Soils (USDA NRCS) Digital Elevation Map (BASINS) Urban Areas (TCEQ) Sub-watersheds & stream network Livestock Stakeholder input Agricultural Statistics (USDA) and Stocking Rates Poultry Operations (TSSWCB) Wildlife Wildlife experts input, Resource Management Unit data for Deer (TPWD) Copyright© Biological and Agricultural Engineering Department, Texas A&M University 4

Example SELECT Inputs/Outputs The following results and stocking rates are from another watershed where SELECT modeling was conducted Modeling Support for Little Brazos River Tributaries Bacteria Assessment (TSSWCB Project #08-55) Copyright© Biological and Agricultural Engineering Department, Texas A&M University

Example SELECT Inputs Grazing Cattle Density: acres per animal (recommended stocking rate) Estimated Population: Land Use Managed Pasture Rangeland Mixed Forest? Deer Density: acres per animal (TPWD estimates) Land Use Rangeland Managed Pasture Mixed Forest Riparian Forest Pine Plantation Copyright© Biological and Agricultural Engineering Department, Texas A&M University

Example SELECT Inputs Septic Feral Hogs Density: acres per animal Land Use Rangeland Managed Pasture Mixed Forest Riparian Forest Barren Land 100 m buffer around streams Septic Gallons of effluent per day per person 106CFU/100 mL bacteria in raw sewage Rural Population (by county, from census) Other Inputs and Parameters Needed Poultry Pets (dogs) Urban areas Copyright© Biological and Agricultural Engineering Department, Texas A&M University

Walnut Creek - Potential E. coli loads Copyright© Biological and Agricultural Engineering Department, Texas A&M University

Walnut Creek-Total Potential Daily E. coli loads Copyright© Biological and Agricultural Engineering Department, Texas A&M University

Thanks! karthi@tamu.edu Copyright© Biological and Agricultural Engineering Department, Texas A&M University