Mourneside Walk, Liskey Road, Liggartown, Sion Mills

The Department's description

Exterior description and setting

Set of iron and timber sluice gates, erected c.1890 on the west bank of the Mourne river, just north of a stone weir, formerly serving Sion Mills.

The north sluice spans the mill race by approximately 10 metres, with a further sluice to the east allowing the mill race to flow into the Mourne river, and having a span of approximately 4 metres.

Each sluice is constructed of large vertical timber beams with cast-iron cappings, and horizontal timbers forming a gate between the vertical beams. A horizontal beam is supported by a series of timber console brackets which supports the cast-iron rack and pinion gears. The smaller sluice to the east has a cast-iron frame with a pair of S-shaped cast-iron brackets laid into the river bed. Both gates now have walkways, steel grid to the east gate and bitmac to the north gate. Rubblestone walling flanks the east gate.

Historical information

The sluice is first captioned on the third edition Ordnance Survey map of 1906 across the mill race leading to the flax spinning mills at Sion Mills. The second edition (1855) captions a ‘Flood Gate’ on the same site, however, the present sluice gate has iron elements of a late-nineteenth or early -twentieth century appearance.

Rynne describes the operation of sluice gates and how these were used to control the flow of water onto water-wheels, “The flow of water in the channel at the entry to it or immediately before its discharge on to the water-wheel was controlled by sliding vertical control gates, called sluices. On the main head race channel, the sluice gates were normally placed at a point near or on the juncture of the main inlet with a weir. By this means, the entry of water into the head race could be carefully controlled, particularly during the winter months when floods were a common hazard, not only to the lands traversed by the mill-race, but to the integrity of the mill-race itself. The sluice gates could also, if required, be used to drain the mill-race for maintenance and repairs.”

“Depending on the power requirements of the mill unit, the width of the head race channel could vary considerably, but the greater the power input the greater the corresponding width required for the inlet sluices, as at Sion Mills, County Tyrone, which has one of the widest sets of sluice gates surviving in Ireland. The revetment walls of large sluice inlets were commonly faced with large cut stone blocks…to counteract erosion. The sluice gates themselves generally consisted of a stout wooden framework, comprising a large sill beam, which extended across the bed of the channel, into which a series of anything from one to perhaps six externally grooved vertical beams were morticed. The vertical gate sections, made up of horizontal boards, were slotted between these uprights, and raised upwards (or closed) by means of cast-iron rack and pinion gears, manually operated with a simple crank.” (p.40-2)

References:

Primary Sources

1. PRONI OS/6/6/10/2 – Second Edition OS Map (1855)
2. PRONI OS/6/6/10/3 – Third Edition OS Map (1905)
3. PRONI OS/6/6/10/4 – Fourth Edition OS Map (1951)

Secondary Sources

1. McCutcheon, W.A. “The Industrial Archaeology of Northern Ireland,” London: HMSO, 1980.
2. Rynne, Colin. “Industrial Ireland 1730-1930: An Archaeology.” Cork: The Collins Press, 2006.

Criteria for listing: architectural interest

Not listed

Criteria for listing: historic interest

Not listed

Evaluation

Reputedly one of the widest sets of sluice gates in Ireland, this example of late Victorian hydro-engineering forms a significant man-made feature in this riverside setting and a reminder of the industrial past of Sion Mills. It is not the type of structure, that on its own, is protected through listing.