Opened in 1851, the site was originally part of both Sandon Dock and Wellington Half Tide Dock, which connected directly to the Mersey via a narrow lock entrance.
At the turn of the 20th century, Sandon Dock was redeveloped and an enlarged half tide dock created, with two larger locks built either side of the original entrance.
After these access channels were sealed in March 1977, the water quality in the dock was noted to have improved.

Between 18 and 21 July 2008, larger vessels participating in the 2008 Tall Ships' Race were berthed here and at neighbouring Wellington Dock.
Opened in 1851, the site was originally part of both Sandon Dock and Wellington Half Tide Dock, which connected directly to the Mersey via a narrow lock entrance. At the turn of the 20th century, Sandon Dock was redeveloped and an enlarged half tide dock created, with two larger locks built either side of the original entrance. After these access channels were sealed in March 1977, the water quality in the dock was noted to have improved.
Between 18 and 21 July 2008, larger vessels participating in the 2008 Tall Ships' Race were berthed here and at neighbouring Wellington Dock.
Sandon Half Tide Dock