Accelerated eutrophication of freshwater bodies continues to be one of the biggest water quality problems globally. However, progress on reducing nutrient inputs to lakes and reservoirs has been slow compared to load reductions for other pollutants. According to the Clean Water Act, a Total Maximum Daily Load (TMDL) must be developed for waterbodies that are listed as impaired. The recent adoption of site-specific chlorophyll-a screening levels for Texas Lakes and Reservoirs is likely to result in several listings for accelerate eutrophication in the coming years. In order to calculate nutrient TMDLs, the regional relationship between chlorophyll, nutrients, and nutrient loading in lakes needs to be quantified. In this study, we used the Texas trophic state database, which houses the long-term total phosphorous and chlorophyll-a for Texas lakes and reservoirs. These data were then used to establish the relationship between phosphorous and chlorophyll-a by concentrations. We also used total phosphorous data along with morphometric and hydrology data to compute phosphorus loading rates. The goal of this project is to identify nutrient load reductions necessary to meet state defined water quality goals for chlorophyll-a levels. Currently, the project is regional but the approach can be applied to other regions in the United States and even worldwide for TMDL development.