The Good, the Bad, & the Ugly: Selecting the Right Nutrient Reduction BMP for Your Specific Circumstances

Gwinnett County, Georgia commenced an effort to identify the most appropriate structural and non-structural Best Management Practices (BMPs) to reduce nutrient pollutant loads that could be contributing to an impaired water listing for chlorophyll-a in Lake Lanier, the County’s water supply source. To achieve this objective the County developed quantitative and qualitative BMP characterization criteria, along with a scoring and ranking approach, that could be used as a basis for selecting BMPs that meet prioritized management objectives. This effort was developed and presented within an excel based decision support tool that allows users to input prioritized characterization criteria and receive ranked BMP recommendations. A web-based version of the tool was also developed. The resulting tool was used by county staff to select several nonstructural BMPs for implementation within the Lake Lanier watershed. Development of the tool also assisted in achieving compliance with obligations contained with the county’s MS4 NPDES permit.