The Port of Long Beach in southern California unveiled its proposal on Tuesday for what it said would be the US’ largest offshore wind infrastructure project, a 400-acre (162-ha) floating wind marshalling and assembly terminal that could cost as much as $7bn.

The so-called Pier Wind proposal would see land reclaimed through dredging in the port’s outer harbour developed into “the largest facility specifically designed to accommodate the assembly of offshore wind turbines in the US”, the operator said.