Bacterial contamination at Huntington Beach, California — Is it from a local offshore wastewater outfall?

During the summers of 1999 and 2000, beaches at Huntington Beach, California, were repeatedly closed to swimming because of high bacteria levels in the surf zone. The city’s beaches are a major recreational and commercial resource, normally attracting millions of visitors each summer. One possible source of the bacterial contamination was the Orange County Sanitation District’s sewage outfall, which discharges treated wastewater 4.5 miles offshore at a depth of 200 feet. Scientists from the U.S. Geological Survey and cooperating organizations have been investigating whether ocean currents and waves transport the wastewater to the beaches. These studies indicate that bacteria from the outfall are not a significant source of the beach contamination.