Septic Area Threat Assessment with Spatial Indexing
(lessons learned)

Switching from onsite disposal systems, usually septic tanks, to sewage treatment is one way to reduce nutrient loading to groundwater and the water bodies downstream. Spatial indexing helps identify trouble areas where conversion to sewer provides greater nutrient reductions to groundwater and the environment. There are several agencies looking at this same issue and using different methods. This poster illustrates one simple method that has been evaluated along with challenges in data acquisition, factor selection, and choice of weighting factors associated with the process. Results from this method of spatial indexing are presented for several Florida locations.