Nearly a quarter-century has passed since an oceangoing ship from Europe
docked somewhere in the Great Lakes and discharged ballast water
carrying tiny but tenacious zebra mussel larvae from Europe.
Within a few years after they turned up in Lake St. Clair, between Lakes
Huron and Erie, the small freshwater mussels and their larger and even
more destructive cousins, quagga mussels, had coated lakebeds throughout
the region, clogging intake valves and pipes at power, water treatment
and manufacturing plants.
The filter-feeding mussels have since helped to upend the ecosystems
of the Great Lakes, fouling beaches, promoting the growth of poisonous
algae and decimating some native fish populations by eating the
microscopic free-floating plant cells on which their food web depends.
“They didn’t just spread — they completely colonized the Great Lakes,”
said Andrew Buchsbaum, director of the National Wildlife Federation’s
Great Lakes office.
Yet it was not until last month that the Coast Guard issued a federal rule
requiring oceangoing freighters entering American waters to install
onboard treatment systems to filter and disinfect their ballast water.
The regulation, which largely parallels a pending international standard and another planned by the Environmental Protection Agency, sets an upper limit on the concentration of organisms in the ballast water.
About 12,000 oceangoing ships moving through United States waters will
be covered by the Coast Guard rules; hundreds reach the Great Lakes
system through the St. Lawrence Seaway. Until now, they were only
required to flush their tanks at sea, a system called ballast water exchange.
The goal of the new rule is not to vanquish quagga or zebra mussels —
scientists assume they are here to stay — but to bar entry to other invasive species like the so-called killer shrimp that are spreading through Europe.
“Some things it’s too late for,” said Andrew Cohen, director of the Center for Research on Aquatic Bioinvasions
in Richmond, Calif. “We’re not going to keep quagga mussels and zebra
mussels from coming to the U.S. They’re here, and we’re not going to get
rid of them.”
But “the damage to come may be worse than we’ve seen,” said Dr. Cohen,
who added that ballast water is a potential source of microscopic
invaders like infectious or antibiotic-resistant bacteria that have
sometimes reached North American waters.
Scientists have tracked at least 329 invaders in marine environments worldwide;
ecosystems have been disrupted from the Great Lakes to San Francisco
Bay, where the Asian clam is implicated in a collapse of fish stocks, to
Lyttelton Harbor in New Zealand, where an invasive fanworm, a prodigious filter feeder, outcompetes local shellfish.
Yet environmentalists, who have long sought a tough ballast rule, worry that the Coast Guard rule and the other proposals are too weak and that the rollout of enforcement will be far too slow to do much good.
For now, the Coast Guard requires only new ships to install the
filtering and disinfecting equipment; others can wait until the next
time they enter dry dock for maintenance or repair, which may happen
only every five years or so. Because some ships do not fall under the
rule until 2016, it could be 2021 before they comply.
“The industry’s had fair warning that this was coming,” said Thom Cmar, a
lawyer for the Natural Resources Defense Council who focuses on Great
Lakes ecosystems issues. “To give an even further compliance extension
on top of what’s already been a long period of delay is unjustified.”
The original proposal by the Coast Guard called for a reappraisal and
tightening of standards in 2016; that was dropped, angering the
environmentalists and some scientists. They say that onshore treatment
plants could be 1,000 times as effective than onboard technology.
Land-based systems could filter ballast with dense and heavy material
like sand, they say, a process that is likely to be difficult to
replicate on a ship, at least not without crowding out cargo. Most
shipboard systems — some 60 have been developed to date — mix and match
different filtration methods, usually pumping water through filtered
pipes. Then they treat the ballast water with chemicals or ultraviolet
light.
The Coast Guard points out that a network of onshore treatment centers
for ballast water has not been developed. Even if it were, said Richard
Everett, the project manager at the Coast Guard’s Office of Operating
and Environmental Standards, “It’s a question of whether we can require a
ship to discharge to shore.” Dr. Cohen said he and other colleagues on a
panel
advising the E.P.A on the issue had told the agency that the panel did
not think present shipboard technology to be the best treatment, in part
because land-based technologies can be more effective.
The shippers themselves prefer a single worldwide standard. Paul A.
Londynsky, vice president for safety, quality and environmental affairs
at the Matson Navigation Company, which is based in Oakland, Calif.,
said: “We go to multiple jurisdictions, multiple destinations. The idea
of having a single standard to meet is much better.”
“We think what the Coast Guard is proposing is very reasonable and
certainly very achievable over time,” Mr. Londynsky added. One Matson
ship has been working with a new onboard system for cleaning ballast
water; Mr. Londynsky said the current generation of ships had no
mechanism for discharging ballast to a shore-based site for filtering.
Whether or not onboard systems are optimal, large international
companies have already sunk considerable capital into developing them.
“There’s a huge investment gone into getting that right, getting that
system within the tight space,” said Frederick Royan, a research analyst
at the market research firm Frost & Sullivan.
The new standards from the Coast Guard, the E.P.A. and the International
Maritime Organization are expected to spawn a booming global market in
such technology, the firm says. Frost & Sullivan predicts that
ballast-water management technologies and their corporate backers will
compete for an estimated $35 billion in sales over the next decade as
the rules take effect.
The E.P.A.’s standard is likely to be made final later this year; the
international standard has yet to muster the required support from 30
countries representing 35 percent of the world’s shipping tonnage.
“It’s a huge cottage industry waiting to happen,” said John Berge of the
Pacific Merchant Shipping Association. “Whoever can come up with the
best mousetrap certainly has a lot of business opportunities.”
Regardless of the financial implications, Tom Nalepa, a biologist
working with invasive species on the Great Lakes, is worried about the
biological ones if the rule is inadequate.
The chief threat on his mind is Dikerogammarus vellosis,
an aggressive freshwater shrimp that feeds on other shrimps and
disrupts food webs. Native to Eastern Europe, it has made its way to
Western Europe in recent years. “Dikerogammarus vellosis is a killer
shrimp,” he said. “If that gets into North America and the Great Lakes,
it’s going to cause as many changes as the zebra mussel.”
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