The Panama Canal, the century-old engineering marvel that revolutionized global trade, is being squeezed shut by drought, forcing shippers worldwide to face a painful choice.

They can wait in line for days or weeks, as low water levels limit the number of ships passing through the 50-mile waterway, carrying cars, consumer goods, fruit and fuel. They can pay millions of dollars to jump ahead in the queue, if a ship with a booked reservation drops out. Or they can sail an entire continent out of the way, sending their ships around the southern tips of Africa and South America, or through the busy Suez Canal.

Each choice adds cost at a time when governments around the world are struggling to tame inflation. And the bottleneck will only worsen in the coming months as Panama enters its annual dry season, which typically begins in December and lasts until April or May.