Each night a line of ships stretches across the horizon off the palm-lined seafront of Panama City. Sometimes more than 20 vessels are queuing here, waiting to travel from the Pacific Ocean into the Atlantic via the lock chambers of the 90-year-old Panama Canal.
The build-up of ships is evidence of how busy the canal, like much of the world's freight transport infrastructure, has become since Asia's manufacturing boom sent trade volumes and demand for shipping soaring. According to Alberto Alemán Zubieta, the canal's administrator, the waterway is operating at 93 per cent of its capacity, even after improvements made as part of and ongoing $1.5bn upgrade.
About 60 per cent of the vessels in the queue will be travelling between Asian ports and the eastern seaboard of the US. Container traffic from Asia to the US will grow 14.3 per cent this year after strong growth in 2002 and 2003, according to Drewry Shipping, a London-based consultancy.
The problems that such fast-growing demand is causing for shipping lines become clear at Balboa, a port at the canal's Pacific entrance. Some of the heavily laden ships off Panama are riding so low in the water that they have to offload containers at the port in order to pass through the canal. This is good for the Panama Canal Railway Company, the operator of an 80km rail link running parallel to the canal, which does brisk business shuttling hundreds of containers each week across the country. But for shippers, such operations add to the cost and complexity of moving goods.
Capacity constraints such as those at Panama have become significant problems for shipping lines and ports around the world. In Europe, many shippers faced a congestion surcharge earlier this year at Rotterdam and Antwerp, the continent's busiest and third-busiest container ports. The charge was levied by the barge operators that carry much of the ports' container traffic inland. In the US, labour shortages at Los Angeles and neighbouring Long Beach, the country's two busiest container ports, meant that, at one point in October, 94 ships were waiting offshore to be unloaded.
Ron Widdows, chief executive of APL, a container shipping line owned by Singapore's Neptune Orient Line, says that nearly all shipping lines would admit their services on most key trade routes are running unreliably.
Mr Widdows faces the same paradox as nearly every other participant in the global shipping and ports industries. The growth of trade from Asia has given rise to a longer, more sustained boom than anyone in the freight industry can remember. But many ports, railways and roads can no longer cope with the traffic being generated. The industry faces unprecedented delays and extra costs as it tries to satisfy rising demand.