Screening chamber (1933), Silent Valley Reservoir, Kilkeel, Newry, Co Down, BT34 4PU

Screening Chamber, Silent Valley Reservoir

This screening chamber at Silent Valley Reservoir is a utilitarian structure from 1933 that demonstrates considerable care in design, embellishment, scale and execution. It forms part of the second phase of the Mourne Scheme, the major water infrastructure project that followed the initial diversion of the Kilkeel River to Belfast in 1901. The building works cohesively with the later screening room (1950), lime dosing plant (1985), and nearby lodges from the early 1900s.

The structure comprises two almost-identical one-storey buildings positioned at the north and south ends of an enclosure. These house subterranean filters that clean water emerging from the reservoir via the scour valve house before it enters the Mourne conduit to Belfast. The northern building serves as a valve house, controlling flow to the screens, while the southern building is a meter house, measuring the quantity of water passing through and monitoring leakage in the conduit.

Both buildings have flat concrete roofs covered with asphalt, topped by low projecting ashlar granite parapets. The walls are constructed of rock-faced granite blocks in irregular courses over chamfered bases, embellished with stepped ashlar quoins. Each building is fenestrated with paired 1/1 wooden windows that open at the top and are bottom-hung, with surrounds of stepped ashlar granite featuring chamfered cills and ashlar stringing above. Double entrance doors are set in slightly proud wall sections facing into the open yard.

The yard is bounded on either side by low walls with rusticated copings and metal security railings, accessed through a pillared gate on the west side. Beneath the concrete floor sits a duplicate set of perforated metal filter screens and an overflow mechanism returning water to the river, accessible via two removable sloping covers sheeted with corrugated metal. A large bronze plaque bearing Belfast Corporation's coat of arms is mounted on the south wall of the southern building.

The chamber was erected by Belfast City & District Water Commissioners as part of the Silent Valley reservoir scheme, with construction undertaken by Messrs S. Pearson & Son of London. Although completed by 1926, the structure only became operational upon the reservoir's opening in 1933. It continues to work in tandem with the 1950 screening room positioned immediately to its north-west.