Potentially hazardous levels of E. coli contamination were found in the Medina River in Bandera City Park and in the Sabinal River at the Lost Maples State Natural Area last month before readings about a week later showed the levels had fallen to more acceptable levels. Water quality testing at Medina Lake and in the Medina and Sabinal rivers at locations across Bandera County is performed regularly by the Bandera County River Authority and Groundwater District to assess E. coli contamination. E. coli is a bacteria found in the gut of warm-blooded animals. If ingested, it can cause illness in humans, a ...