Towing giant ships with tiny tugboats (pictures)

SAN FRANCISCO BAY -- What happens if a giant container ship loses power and needs to be towed to safety?

Because of new legislation in California that aims for cleaner air, ships are now using a different kind of fuel that has one big downside: they can't always process it properly, and are increasingly losing power, says Deb Self, executive director of San Francisco Baykeeper, a proponent of clean-water laws.

Last Wednesday, a coalition of marine groups in the San Francisco area known as the Harbor Safety Committee conducted a first-of-its-kind exercise to find out how to handle what could be a catastrophic emergency in an area full of sensitive ecosystems. The exercise consisted of towing an ultralarge container vessel that has no power.

The CMA CGM Centaurus was the container ship used in the exercise. At 1,200 feet long, and carrying 11,000 containers to Russia, the ship presented an untried challenge for an exercise of this magnitude in American waters.

Crews aboard the CMA CGM Centaurus worked to tie a tethering line from the ultralarge container vessel to one of the three tugboats that were on hand for the exercise.

A side view of a tugboat towing the giant container ship in the San Francisco Bay last Wednesday.

A view of the tugboat towing the CMA CGM Centaurus gives a sense of the magnitude of the job.

After about an hour of towing the container ship, it was time to turn around. To do that, one tugboat went alongside the ship and pushed it, while another tug pulled it from the front, essentially spinning the ship around 180 degrees.

Although the exercise showed that one tugboat was capable of towing the giant container ship, organizers also tried it with two tugs.

After the exercise, the ship, with power returned, sailed towards the Golden Gate on its way to Russia.

It might be hard to believe that a ship carrying 11,000 containers could be pulled by a single rope, but the exercise showed that it's quite possible.