Marion County Democrats will host a free public event regarding water quality at 6:30 this evening at the Grand Theater in Knoxville. The committee tells KNIA/KRLS NEWS that water quality and sustainable agriculture are important, with record nitrate levels being recorded at Lake Red Rock. There will be a 30-minute screening of the documentary Big River, and Dr. Francis Thicke will discuss the dead zone in the Gulf of Mexico, following the film. Dr. Thicke has a PhD in agronomy and soil fertility and has been a National Program Leader in Soil Science for the USDA in Washington DC.