Selby Canal, Paperhouse Tunnel

This canal culvert dates from 1778 and was designed by engineer William Jessop for the Aire and Calder Navigation Company. It is constructed from limestone and gritstone, with timber foundations.

The culvert comprises a pair of sumps with inverted, semi-circular plans and walled channels, lined by headwalls that have open backs and no drainage channel feeders. These sumps are connected by four culvert tunnels running beneath the canal bed. The northern ends of the waterway channel walls splay outwards to form a distinctive 'wine-glass' plan, meeting the abutment walls of Paper House Bridge.

The headwalls of each sump are capped by gritstone blocks stiffened by wrought-iron staples, with recesses for timber railing posts secured by wrought-iron straps set in lead. Below the capstones are three courses of large ashlar limestone blocks, laid upon a band of four courses of smaller blocks that form a circular band around the structures. The wing walls are stepped, with a recessed central panel containing four segmental stone arch culverts that lead to the opposite sump.

The western headwall has an upstand where the towpath descends to the lower western waterway channel wall, which is approximately 1.2 metres lower than the parallel eastern wall. The western channel wall then rises back to the same height, with a section of dry-stone retaining walling supporting the canal bank. The eastern channel wall’s splay terminates similarly, creating a canal channel approximately 5.77 metres wide between the two parallel walls. The open rears of both sumps are now filled with silt and surrounding ground.