Human enteric viruses (HEV) are recognized by the CDC as common etiological agents for waterborne outbreaks and they have been detected in recreational waters in the US and around the world. Current concentration and detection methods present challenges to study of HEV in coastal waters and have prevented the routine monitoring of HEV in recreational or shellfish harvesting waters. In this dissertation, various methods of concentrating viruses from water were investigated. A two-step viral concentration method that included viral adsorption-elution and ultrafiltration was found to be effective for the concentration of total viruses and improved detection limits for HEV in coastal waters. This method was then applied in a time series study of human viral contamination to coastal recreational waters. RT-PCR was used to screen for three types of HEV: enteroviruses (EV), hepatitis A viruses (HAV) and noroviurses (NoV) in viral concentrates from surface waters of Port Jefferson Harbor (PJH) NY, which receives point and nonpoint sources of human waste. No HAV or NoV were detected in any samples, but EV was detected after precipitation events. Cloning and sequencing of the EV-positive samples revealed that the amplicons derived from strains of poliovirus. The results suggest that storm water runoff, which is discharged directly into the harbor, results in human viral contamination. Future studies of HEV sources and occurrence in the environment will help reduce public health risk to human viral pollution and transmission into coastal recreational waters, particularly after precipitation events.