Intercepting Weir, Dunnywater, Annalong, Newry, Co Down

This is an intercepting weir built between 1900 and 1919 as part of the Mourne Scheme, designed to supply Belfast with water. Constructed by Fisher and Le Fanu for the Belfast & District Water Commissioners, it opened in 1901. The weir diverts water from the Annalong River into the Mourne Conduit. It features a sloping masonry apron with a steel weir plate across the cill, and a concrete bypass pipe running midway along the weir. The left bank is faced with granite blocks. Immediately upstream from a concrete footbridge, is the intake pipe which leads to a nearby well house and eventually to the Conduit. A small, modern flow gauging station is positioned over this intake point. Originally, a simple wooden hut existed at the abstraction point, but this is no longer present. While most water is now abstracted further upstream, this weir and intake remain in use. The footbridge dates to circa 1964. The structure is of industrial archaeological interest and holds group value due to its functional connection with the nearby well house and Mourne Conduit. It provided Belfast’s sole water supply from the Mournes prior to the Silent Valley reservoir's opening in 1933.