SS4.13 Water Quality of Lakes, Rivers and Coastal Zones
Date: Thursday, June 13, 2002
Time: 9:30:00 AM
Location: Carson B
RoseJB, University of South Florida, St. Petersburg, USA,
Florida has 1000 miles of coastline and approximately 15 million people predicted to grow to 20 million. On-site disposal systems (septic tanks) are used by 30% of the population, and they contribute an estimated 210 million gallons of waste every day to the subsurface. In addition, sewage disposal through outfalls and to freshwaters and injection wells are directly or indirectly discharged to coastal systems. Over the last 10 years, we have studied microbial water quality in fresh waters and coastal near shore waters to examine anthropogenic sources, impacts and transport and fate through the monitoring of indicator organisms as well as human enteric viruses. Recently the role of climate in exacerbating the situation has been examined. Overall between 70% and 95% of the sites surveyed from the West Coast of Florida to the Florida Keys tested positive for enteric viruses using both conventional and molecular based techniques. The contamination was event driven and could be related directly to rainfall, streamflow and water temperature. We have recently reported on the first direct evidence that constituents from human wastes are reaching the coral reefs in the Florida Keys. Enterovirus nucleic acid sequences were found in 93.3% of coral reef mucus surface layers. Land use, rainfall (increase) and water temperature (decrease) can be used to predict virus contamination of shellfish harvesting areas with 97% concordance. It is now clear that changes in temperature, rainfall, el nino cycles will influence the distribution of water quality both temporally and spatially