The extension, built by Peel Ports, officially opened on 4 November 2016 and is an expansion of the Seaforth Dock container terminal.

[4] By July 2014, dredging of a 27 km2 (10 sq mi) area of the River Mersey approach channel had been commenced by Van Oord.

[5] The extension was built on reclaimed land using the material dredged from the River Mersey,[6] with the deepened approach channel providing the necessary clearance for visiting ships.

[14] A first batch of six ZPMC-built cantilever rail-mounted gantry cranes were delivered to the site in May 2016,[15] arriving from Nantong aboard the ship Zhen Hua 25.

[11][18] The extension was built at a cost of £400m and ultimately opened on 4 November 2016 by Liam Fox, the Secretary of State for International Trade.

[26] The terminal extension is able to accommodate two 13,500 TEU New-Panamax vessels simultaneously,[27][28][29] the maximum size that can transit the Panama Canal.

[36][38] Consideration has also been given for improved road access to the terminal, from the M57 motorway junction at Switch Island, in order to ease the expected HGV congestion.