Excavations carried out under licence in 1993 uncovered a millrace feature measuring four metres long and three and a half metres wide, built from sandstone and fitted with arched openings in both its eastern and western faces. A millrace is the channel that directs fast-flowing water onto a mill wheel, and this particular example had been substantially modified over time, with several additional walls built up against and around the original structure.

The dating evidence recovered during the dig places the millrace to before the close of the seventeenth century, though quite how much earlier it might extend remains unclear. One detail that points to careful original construction is the presence of a cutwater along the eastern face, a projecting wedge-shaped element designed to divide the current and reduce the force of water pressing against the stonework. It is the kind of practical engineering detail that rarely survives, and its presence here suggests the feature was built to manage a meaningful flow. After excavation, rather than being removed, the remains were retained in situ by the developer, preserved beneath whatever now sits above them.