Marple Aqueduct Parapet

Marple Aqueduct is a Grade-I Listed structure and Scheduled Ancient Monument in Greater Manchester. Constructed in 1800, it carries the Peak Forest Canal over the River Goyt. The 112m long structure consists of three semi-circular masonry arches 30m above the valley. As with most aqueducts in the UK, a parapet was only provided on the towpath side, leaving an unprotected drop on the offside.

The brief called for the addition of a parapet that would be visually understated to avoid detracting from the historic structure. The solution consists of a horizontal rail fixed to uniformly spaced vertical posts comprising two legs, one vertical and one raking. Brought to site by canal barge as preassembled units, the parapet was anchored to the existing concrete, with the main base plate hidden under the gravel layer, leaving only intermittent fixings to the aqueduct coping stones. This allowed minimal disturbance of the historic structure and suited the desire for a module-free appearance.

The detailed design was inspired by the concept of weaving, highlighting the aqueduct’s historic relationship to the nearby cotton industry at Mellor Mill. The vertical black steel posts act as the “warp” wrapped around the horizontal stainless steel “weft”, producing interesting patterns in oblique views. The parapet form and careful colour scheme result in maximum transparency when it is viewed against the sky or from the neighbouring railway viaduct.