SAN FRANCISCO (KCBS) – The Environmental Protection Agency Thursday signed a rule that bans cruise ships and other large vessels from dumping sewage within three miles of California’s coastline. Federal officials estimate this will cut down on 90 percent of the sewage that could previously be discharged legally.

US EPA Regional Adminstrator Jared Blumenfeld announced one of the strictest laws in the nation regarding vessels over 300 tons.

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“The EPA is acting to prevent a previously legal source of pollutants from large cruise ships, and most other ocean-going ships,” said Blumenfeld.

The previously legal source was treated sewage, but California Secretary for Environmental Protection Matt Rodriguez said that it’s been determined that even treated sewage can cause harm.

“That sewage often contains high levels of bacteria, nutrients and other pollutants that can cause illness to swimmers, harm fish, harm marine mammals, and it triggers the growth of aquatic plants and algae that foul beaches,” said Rodriguez.

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KCBS’ Anna Duckworth Reports:

The request for federal regulation came from State Senator Joe Simitian of Palo Alto, who calls it an environmental, public health and economic growth issue because fishing, tourism and water recreation are important industries for the state. He said the action means the coast will no longer be a dumping ground for big ships.

“This is the largest no-discharge zone in the nation,” said Simitian. “Every single mile of the California coastline is protected in this way.”

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