The watercourse, roughly two metres wide and a metre deep, was engineered to carry water from a point adjacent to a large building on its eastern end, running south for about forty metres, then turning west-north-west for around a hundred metres, and finally bending south-west for a further ninety metres before reaching a mill approximately five hundred metres to the south. A mill-race of this kind was essentially an artificial channel designed to deliver a controlled flow of water to power a mill wheel, and the stone facing visible in places along this one suggests it was built to last and to prevent the banks from collapsing under the steady pressure of moving water.

What makes the setting particularly layered is the proximity of the channel to the remains of a church associated with Arroasian nuns, situated some ninety to a hundred and thirty metres to the north. The Arroasians were a reform congregation of Augustinian canons and canonesses whose rule spread into Ireland during the twelfth century, and their houses were often modest but purposeful communities embedded in working landscapes. The large building adjacent to the eastern end of the watercourse sits within that same cluster of remains, and the mill-race appears to have been laid out in relation to it, suggesting that the nineteenth-century milling operation was drawing on an infrastructure, or at least a topography, already shaped by earlier occupation of the site. The slope, the water source, and the orientation of the channel all reflect a practical logic that would have been as legible to a medieval monastic community as to a Victorian miller.