Four massive steel gates have arrived on the Atlantic side of the Panama Canal as construction ramps up on an unprecedented expansion of one of the world’s most important engineered waterways.

In its latest announcement, the Panama Canal Authority says the gates – the first of 16 to be used in the project – arrived on the waterway’s Atlantic side on board the semi-submersible vessel STX Sun Rise on the morning of August 20 (see video).

Weighing no less than 3,100 tonnes, the gates measure 57.6 metres long, 10 metres wide and 30.19 metres tall and are set to be transported to their final position on the Atlantic side using the same self-propelled motorised wheel transporters that are used to load and unload cargo from the ship.

The arrival of the new gates is part of a massive expansion of the Canal, which since its original completion in 1914 has allowed ships to cut through Panama instead of going around the much longer and more dangerous rough past Cape Horn on the southern tip of South America and thus has long been an integral part of the integration of the US West Coast and Pacific nations into the world economy.

The expansion, considered by its proponents necessary in order to alleviate capacity constraints as US trade grows with Asia, the Middle East and elsewhere, will see the Canal’s capacity double upon completion in 2015, and will allow for more and bigger ships to pass through.

The gates will form part of a critical aspect of the expansion which involves opening up a third lane of traffic featuring two new locks (one each on the Atlantic and Pacific sides), each with three chambers with water saving basins, and excavation of new channels for the locks. Each of the locks will have eight rolling gates.

Other works include the widening and deepening of existing channels and the raising of the maximum operating level of Gatun Lake – an artificial lake in Panama which forms a significant part of the Canal and carries ships for 33 kilometres of their transit across the narrow strip of land that lies between the Caribbean Sea and the Pacific Ocean.

Panama Canal administrator Jorge L. Quijano says the arrival of the new gates marks a significant milestone in an expansion he says is now 62 per cent complete.

“This is an exciting moment for the Panama Canal – the arrival of the new gates marks a great progress for this engineering project” he says. “With the expansion, we will further reinforce our position as the maritime and logistics hub of the Americas.”

Built by subcontractor Cimolai SpA, the new gates are being shipped four at a time from Italy, and will be loaded onto a temporary dock until ready for installation.

Unlike the current Canal, which uses miter gates, the gates for the new locks and laneway are steel rolling gates.