Brush I - Texas State Soil and Water Conservation Board
Modeling of the Upper Colorado River, Concho River, and Wichita River evaluated the feasibility of using brush management within each watershed to increase the water yield to downstream municipal water supply reservoirs. The SWAT model was calibrated to historical flow records and then brush removal was simulated to assess the effects.
Using ground control points (GCPs) collected by NRCS field staff, the land use and cover was classified from Landsat satellite imagery. The radiometrically and precision terrain corrected imagery was selected to obtain relatively cloud-free scenes during the growing season for the project areas. A supervised maximum likelihood classification of the image was then performed with the spectral signatures for various land use classes. The GCPs were used to perform an accuracy assessment of the resulting image. NRCS field personnel further verified a sampling of the initial classification. The use of remotely sensed data and the process of classifying it with ground truthing resulted in a current land use/land cover GIS map that included more detailed brush cover categories (classified by species and density).
As a result of this study, the Texas Legislature appropriated funds for cost sharing brush removal with landowners.