ROBERT SIEGEL, host:
California is cracking down on invasive species, and that could have a big impact on national regulations due later this year. The state has passed the strictest rules in the country to prevent cargo ships from bringing foreign plants and animals into San Francisco Bay.
But as Lauren Sommer reports from member station KQED, the standards are so tough the state may not be able to enforce them.
(Soundbite of vehicles)
LAUREN SOMMER: Trucks and cranes spring into action as a 900-foot container ship docks here at the Port of Oakland. Every year, thousands of ships pass under the Golden Gate, bringing cars, sneakers, computers and...
(Soundbite of splashing water)
Dr. ANDREW COHEN (Director, Center for Research on Aquatic Bioinvasions): So let's see. We've got one, two, three exotic organisms - four exotic organisms.
SOMMER: Biologist Andrew Cohen, of the Center for Research on Aquatic Bioinvasions, slogs through a muddy beach in the eastern Bay Area. He scoops up a clump of seaweed that's home to clams, snails, strange globs.
Dr. COHEN: And those yellow dots are the egg, egg mass of a Japanese sea slug which showed up here a few years ago.
SOMMER: Biologists have found hundreds of invasive species in San Francisco Bay, which Cohen says makes it one of the most invaded estuaries in the world.
Mr. COHEN: Anytime I go out into the bay, there's a reasonable chance I'm going to find something I've never seen in the bay before, something which no one has seen on the Pacific coast before. That's just astonishing.
SOMMER: Most of these invaders arrived as international hitchhikers. Ships that carry cargo on the open ocean have to balance their loads. So, Cohen explains, they fill massive onboard ballast tanks by pumping seawater in at one port and pumping it out at the next.
Mr. COHEN: For a long time, people didn't think too much about this because it was just water. But eventually, we found that we were moving virtually everything that lived in the sea.
SOMMER: Including parasites that cause rashes and the Asian clam that altered the entire food web in San Francisco Bay. California has spent millions trying to get rid of the worst invasive species. But the state's efforts have rarely worked, so the strategy has turned to prevention.
Mr. BILL DAVIDSON (Engineer): The ballast tanks that we use are right above us.
SOMMER: Inside the Golden Bear, a 500-foot ship at the California Maritime Academy in Vallejo, engineer Bill Davidson switches on the ballast pumps.
Davidson is testing new ballast water treatment technology. The idea is pretty simple: kill the organisms in the water before the ballast is released. The system has two steps. First, the ballast water is filtered. Then, chlorine is added.
Mr. DAVIDSON: And you take this chlorine and feed it back into the ballast stream, and so that will ideally oxidize or kill any live organisms.
SOMMER: The treatment system neutralizes the chlorine before it's released, which makes it inactive. But getting this system to work is trickier than it seems because the organisms are very, very small.
Ms. JULIE KUO (Moss Landing Marine): So right in your center field of view, that's a tintinnid.
SOMMER: In a lab on the ship, Julie Kuo of Moss Landing Marine Labs looks through a microscope at a tiny cone-shaped plankton. Kuo counts these organisms in water samples from the treatment process and, most importantly, sees if they're dead.
Ms. KUO: They're kind of sitting there, and you don't know if they're alive or dead, you poke them with a probe.
SOMMER: This treatment system is designed to meet international standards that limit the number of living organisms in ballast water. Right now those standards are voluntary. But California has adopted a rule that's a thousand times tougher. It applies to all newly-constructed ships starting next January. The only problem is the technology to meet California's standard isn't ready.
Ms. NICOLE DOBROSKI: We recognize that that's a challenge, but there's a good reason we wanted it to be a challenge.
SOMMER: Nicole Dobroski is with the California agency overseeing the regulation. She says none of the treatment systems being developed can consistently meet California's standards yet. Still, the state is moving ahead with the regulation.
Ms. DOBROSKI: We wanted them to be innovative. We wanted them to think out of the box.
SOMMER: Which would mean ships across the globe would also have to think out of the box. Almost half of all the cargo brought into the U.S. in shipping containers comes in through California ports.
For NPR News, I'm Lauren Sommer in San Francisco.
NPR transcripts are created on a rush deadline by a contractor for NPR, and accuracy and availability may vary. This text may not be in its final form and may be updated or revised in the future. Please be aware that the authoritative record of NPR's programming is the audio.