Health Risks Associated with Swimming in Beach Areas Contaminated by Urban Runoff

TitleHealth Risks Associated with Swimming in Beach Areas Contaminated by Urban Runoff
Publication TypeConference Paper
Year of Publication1997
AuthorsWang, G-yu
Conference NameInternational Medical-Rescue Conference
Date Published09/1997
PublisherInternational Life Saving Federation
Conference LocationSan Diego, California, USA
Call Number30
Other Numbers265
Keywordsepidemiology
Abstract

This presentation discusses the possible health risks associated with swimming in beach areas contaminated by urban runoff, based on the results of an epidemiological study conducted in Santa Monica Bay during the summer of 1995. The study was conducted in response to wide public perception and evidence about such health risks.

Over the years, there have been a number of studies of human illness associated with recreational exposures to contaminated waters. However, most of these studies focused on areas impacted by direct sewage discharge. The possible health impacts of urban runoff carried through a city’ storm drain system have generally been overlooked by public health professionals. In Southern California, because sewer and storm drain systems are completely seperate, most people tend to believe that urban runoff does not contain human sewage and therefore should not impose health risks.

In recent years, new evidence have shown that there may be health effects associated with recreational exposures to urban runoff. In the Santa Monica Bay area, there have been anecdotal reports of illness caused by swimming near storm drain outlets on beaches. High levels of bacterial indicators were frequently observed in beach areas near flowing storm drains. In several investigations conducted by the Santa Monica Bay Restoration Project in the early 1990s (SMBRP, 1992, 1991, 1990), human pathogens were detected in summer runoff. People also realized that there are possible sources of pathogens contamination into the storm drain system. These sources include illegal sewer connections, leaking sewer lines, malfunctioning septic systems, illegal dumping from recreational vehicles, or direct human sources such as campers or transients. These circumstances provided the motivation to conduct a large-scale epidemiological study of the possible health effects of swimming in runoff contaminated waters.