The final caisson went into the sea at Jidiao wharf, in Jinjing Bay, on the western part of Pingtan Island, Fujian province, on June 10, marking the beginning of a new phase in construction work on berths No 2 and 3.

A total of 36 caissons for the two berths have been installed, since May 2012, as part of five berths to be added to the wharf, at a cost of up to 400 million yuan ($65 million). Each caisson is 20 meters long and 20 m wide, 18.2 m high, and weighs 3,000 tons.

More than 2,200 cu m of concrete has been poured to form walls around the two berths. Construction work on No.4 and 5 has started, workers report.

A caisson is a watertight retaining structure used for engineering work on the foundation of a bridge pier, for building a concrete dam, or for ship repairs. They are in such a way that water can be kept out to allow the work area to dry.

Edited by Chen Zhilin and Roger Bradshaw