A new study shows that fecal bacteria from sewage are living in far greater quantities in near-shore sediments of the Hudson River than in the water itself. The river’s pollution levels are generally monitored based on samples of clear water, not sediments, so the findings suggest that people stirring up the bottom while wading, swimming or kayaking may face previously unrecognized health risks. Germs may persist for long periods or even reproduce in the sediments, say the authors. The study appears in the early online edition of the journal Science of the Total Environment.