One thing I’ve learned lately is that ballast water tanks that
ships use for stability can cause big headaches. For one thing,
when filled with water they can act like an aquarium for all
kinds of critters and carry them across oceans. Those species
can set up shop in a whole new spot once they get dumped
overboard at the next port of call. For another thing, swapping
ballast water in mid-ocean — the technique required by the U.S.
and many other governments as a way to get rid of unwanted
hitchhikers — can be dangerous. One freighter literally flipped
on its side when a mid-ocean ballast water exchange went wrong.
I wrote about all this in an article for Chesapeake Quarterly
last June, where I noted that many were calling for a change in
approach to better protect ecosystems from invasive species. Now
the beginnings of change have come. On August 28th, 2009, the
Coast Guard published proposed rules that include standards for
treating — not exchanging — ballast water. This opens the door
for installing systems