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Marsh spews bacteria onto beach

Human-made wetlands do not act as good water filters suggests report that connects a restored coastal marsh in California, USA, with the contamination of a nearby beach. Persistently high levels of faecal bacteria forced the temporary closure of Huntington Beach in southern California in 1999 and led to a hunt for the bacteria's source. Water from nearby Talbert Marsh was found to pick up bacteria from bird droppings as it flowed through the marsh and out towards the Pacific Ocean. By injecting a dye into the marsh outlet, the researchers found that dyed water was sometimes washed back to the beach by waves ( www.nature.com/news , June 18, 2001).