Canal culvert completed by 1778, designed by William Jessop engineer, for the Aire and Calder Navigation Company.
Reasons for Designation
Tankard's Culvert, 1778 by William Jessop, is listed at Grade II for the following principal reasons:
* the tunnel culvert was completed for the Aire and Calder Navigation Company in 1778, during the 'Pioneer Phase' of the Canal Age;
* the canal structure pre-dates 1830 and survives in its original form, largely unaltered and retaining significant original fabric;
* it was built as an ingenious engineering solution to alleviate the threat of the Selby Canal being inundated and damaged by flood water;
* it is a very rare form of early canal structure.
* the tunnel has a strong historic association with their designer William Jessop, who is recognised as being one of the most eminent canal engineers of the C18.
* the culvert tunnel share a functional and spatial group value with three similar tunnels and several listed structures along the length of the canal.
Following the turning down of a submission to Parliament to improve the river navigation of the River Aire below Haddlesey in 1772, the Aire and Calder Navigation Company sought an alternative route to improve the flow of river traffic, and employed William Jessop to carry out the work. At the time of his commission, he was working under John Smeaton and surveyed the new canal route, linking the River Aire to the River Ouse from West Haddlesey to Selby. As his Oxford Dictionary of National Biography entry makes clear, Jessop was a resourceful but cautious engineer, with a pragmatic approach to problems producing affordable solutions, which resulted in him being considered the 'first engineer' of the Kingdom. The company then submitted the proposals for the Selby Canal to Parliament in 1774, and an Act of Parliament was granted to the company on 14 June. Construction work began early the following year with William Jessop acting in his his own right as the principal engineer, John Gott as resident engineer, and James and John Pinkerton being the main contractors. The six mile long canal was completed with relative ease and was opened three years later on 29 April 1778 costing £20,000. The low-lying and flat countryside enabled it to be built with a minimum of costly engineering, entailing the construction of only two locks, eight bridges, and the dock facilities at Selby. Nevertheless the fact that the area was prone to flooding did require Jessop to design five ingenious tunnel culverts beneath the canal to prevent it from being damaged or inundated by floodwater: these were sited at West Haddlesey, Paper House Farm, Lund, Brayton, and The Vivars, Selby; the latter was in-filled by an uncertain date. Although varying in detail, all of the tunnels consisted of a pair of roughly D-shaped collection ponds or sumps either side of the canal channel, linked by a culvert tunnel or culverts passing beneath the canal. The sumps were originally protected by two bar timber fences, but these have since been replaced by a mixture of modern tubular steel and timber fencing.
By 1800, Selby Canal was handling in the region of 369,780 tons of cargo per year; however its very success was also its undoing as the huge volume of traffic was causing delays and congestion at Selby. Consequently the Aire and Calder Company opened a new cut to Goole in 1826 which became the main destination for their traffic and caused the steady decline of the Selby Canal. Nevertheless, it was widened and deepened in 1828, further improvements were made in the 1830s, and again between 1885 and 1886, but none were sufficient for it to regain much of its past trade apart from that heading to York. The slow decline continued in the C20 but it gained an additional role during the Second World War when a Buffer Depot was established at Selby as an emergency food store with access to the canal system.
Post-war, the canal was nationalised in 1948 and was brought under the control of the British Transport Commission. A turning point was reached in 1962 when British Waterways marketed it as part of a through route to York with a consequent increase in pleasure boat traffic, which has steadily grown to over 2,000 boats using the canal each year. In July 2012 all British Waterways' assets including the Selby Canal were transferred to the Canal and River Trust.
Canal culvert, designed by William Jessop engineer for the Aire and Calder Navigation Company.
MATERIALS: limestone and gritstone headwalls, wing walls, waterway channel walls, and culverts, built on timber foundations.
PLAN: a pair of inverted horse-shoe plan walled sumps lined by headwalls with open backs, to either side of a walled waterway channel, linked by two culvert tunnels beneath the canal bed. The waterway channel walls have depressed angled U-plans, with straight lengths of wall that are splayed out at either end.
DESCRIPTION: each sump headwall is capped by a course of gritstone blocks, into which recesses have been cut to receive timber railing posts that were retained by wrought-iron straps fixed in lead. Below the capstones are two courses of large ashlar limestone blocks; below this level the inner face of the sump is battered by stepped stone courses, which terminate either side of a recessed vertical central panel set at the internal apex of the sump, with two 1.75m high segmental stone arch culverts at its base. The two culvert tunnels pass beneath the canal channel to the opposite sump. The upper surface of the two sumps have a grass surface and the western surface acts as the towpath. The headwalls above the wing wall sections of the west sump rise one course in height before their termination on the landward ends. The open rear ends of the sumps are blocked by silt and changes in ground levels and do not have drainage channels. The opposing parallel masonry waterway channel walls form a 5.77m wide passage through which the canal passes; the ends of the channel walls splay back and the terminations of the wall ends abut lengths of dry-stone bank revetments, marking the junction with the adjacent canal banks.