Both the Exxon Valdez and the Jessica, which hit rocks on the Galapagos coast 10 days ago, were single-hulled tankers. Critics have been quick to point out the link. The wisdom of double hulls for tankers has become enshrined in the laws of OPA 90, passed by the United States in the wake of the Exxon Valdez crude spill, which destroyed wildlife and fish stocks in Anchorage, Alaska in 1989.
Experts are far from agreed on the value of double versus single hulled vessels.
But shipping experts said Exxon's choice of a single-hulled vessel needs closer examination. But a good single-hull ship is the best design in the world. Spencer said that the enclosed ballast spaces between the double hulls were difficult to inspect and to maintain. Double-hulled ships also were subject to extremely high stresses. Greenpeace's Paul Horsman agreed with Spencer that the older generation of ships were strongly built.