During the post-medieval period numerous industries grew around the port of Frodsham including a salt works which was established in the late seventeenth century. However, a bill was passed in 1721, known as the Weaver Navigation Act, to enable the river to be navigable further inland toward the town. This was due to pressure from traders and manufacturers as the movement of goods from Frodsham port by packhorse inland was proving to be costly. By 1732 the Weaver was made fully navigable, but it was not until 1780 that Frodsham Lock and Cut were constructed as improvements to the navigation. The Wharf and its facilities encouraged more industry after the construction of the Weaver Navigation in the early eighteenth century.
Frodsham Cut was built in the late eighteenth century as an improvement to the existing natural rivers route saving time by 'cutting' through the marsh hence the name, and creating a docking point of sorts closer to Frodsham. The lock was necessary as the river was tidal prior to the building of the Manchester ship canal where it now begins at Weston Point rather than at the Mersey, but by the early nineteenth century the cut itself had been by-passed by the Weaver Canal to the north, which was much wider and could facilitate larger vessels. The lock slowly fell out of use as the occasional local traffic also began to prioritise the newer and quicker navigation route to the north. The sluice gate was therefore added in 1908 shortly after the above photo, presumed to be around 1900. Its purpose was to maintain the level of the cut and in turn the canal in the absence of regular use of the lock, and it still remains in unattended use silently allowing water to pass through. Since the lock closed, the entire southern route of the weaver that runs closer to Frodsham has been unnavigable, with the large sluice gates joining the northern route at Sutton having no locks for passing vessels meaning the western side of the cut remains a dead-end. The lock keepers cottages seen in the 1900 image were therefore demolished in due course. The lock may be heavily derelict, but it remains as one of the oldest canal locks in Britain, and together with the weir gained listed status in 1980 to protect their history from removal.