Darley Abbey Weir

This is a weir complex, constructed around 1782, situated in the River Derwent, immediately west of the Grade I listed former Boars Head Mills. The structure measures approximately 110 metres in length and is built of coursed square gritstone blocks.

The weir complex consists of three main sections. To the north is a 20-metre long, concave, sharp-crested weir that curves upstream, and a 40-metre long stepped spillway to the south. A coursed gritstone block wall, perpendicular to the spillway, stands to the south of the spillway and contains two floodgates. These floodgates connect to a natural island located to the south (which is excluded from this assessment). The height of the weir is approximately 1.8 metres, and the floodgates have a depth of 1.2 metres.

South of the island is a 25-metre long sharp-crested weir, along with a fish weir. A 21st-century footbridge, supported on metal supports, spans the river above the weir. The north and south weirs are linked by a stone wall revetment running around the northern and western edges of the island and topped by a 21st-century post and rail timber fence. A modern fish weir cuts through the wall on the north-western edge of the island, but the original stone was retained and reconstructed to match the surrounding stonework.

The 21st-century footbridge and timber post and rail fence, along with the metal supports for the footbridge, are not considered to have special architectural or historic interest.

The weirs are part of a larger water management system associated with the late 18th century Boars Head Mills at Darley Abbey, including mill races from the River Derwent to the mill complex, sluice gates, and tail races from the mill complex back to the river. Only the weirs have been assessed for listing purposes.