This portion of the river at Low Southwick was a shipyard, leased to the Dixon family between the 1820s and 1840s from Stafford John Esq as stated in the tithe apportionment of 1840. It was adjacent to the Carr Shipyard (https://www.northeastheritagelibrary.co.uk/shipbuilding-archive/swi002/low-southwick%2C-carr-shipyard)

It has proved incredibly difficult to trace their lineage, especially given their common surname. I have tracked Henry and William, the former supposedly born in Durham in the 1780s. He is noted as a shipbuilder living at Collier Row in Southwick with William. Given it was a separate village, there's a reasonable chance the family could have lived elsewhere in modern Sunderland too.

Their first recorded ship is the Loyal Standard, a cargo Snow built for Thomas Hodgson, Charles Adie & John Rennie of Sunderland. This was their staple build, alongside limited schooners, barques and brigs.

It appears Thomas & William ceased building by 1840, with Henry taking the reigns for another 4 years. By the time of the first Ordnance Survey map surveyed in 1855, the site is composed of a Bottle Works and a steep hill - potentially ballast or waste.