The Effects of Plain Sedimentation on the Quality of Urban Stormwater Runoff from the Lake Eola Watershed

The settling characteristics of urban stormwater runoff emanating from the Lake Eola Watershed (Orlando, Florida) were evaluated through a series of 7 column studies. The percentage removal that occurred due to sedimentation was observed for various stormwater pollutants and constituents. These included the General Water Quality Parameters: Total Suspended Solids, Non-volatile Suspended Solids, Volatile Suspended Solids, Chemical Oxygen Demand, Total Kjeldahl Nitrogen, Ammonia Nitrogen, Total Organic Carbon, and Total Phosphorus. The metals parameters: Zinc, Cadmium, Arsenic, Nickel, Copper, Magnesium, Iron, Lead, Chromium and Calcium were also considered. The results of the settling analysis indicates that the quality of Lake Eola stormater can be improved by plain sedimentation of detention as convincing removals were displayed by the solid parameters displayed trends of weak removal. Regression equations were developed that describe percent removal as a linear and logarithmic function of time and settling velocity. Isoconcentration lines were also developed for total suspended solids and total phosphorus removals. In addition, the effect of this treatment on the productivity of Lake Eola was assessed in terms of existing trophic state models