Cassy Water Bridge, Near 381 Killowen Road, Killowen, rostrevor, Newry, Co Down, BT34 4SF

The Department's description

Exterior description and setting

This twin-arch granite bridge carries the main Kilkeel – Rostrevor road over the Cassy Water. The arches are equal in size and skewed. Only the west one is in normal use. Both are embellished with rusticated voussoirs. The squared rubble soffit stones are set on the skew, not orthogonally. The abutments and pier are of regularly coursed roughly dressed granite blocks. There is a rounded cutwater on each side, rising to a shallow dome at arch spring level. The spandrels and parapets are of squared rubble; the latter are coped with large blocks. The approach walls on either side are of random rubble. There is a slight hump on the road and a footpath runs along the downstream side. The total width of the bridge is 8.9m (including 0.45m thick parapets); there is no evidence of any widening.

The bed of the river is paved with granite and makes four shallow steps immediately downstream of the bridge. The three upper steps are of cement-rendered rubble, but the bottom one survives as large squared blocks. This arrangement was designed to minimise scouring (and thus undercutting of the foundations) and slow up flood water passing through the arches.

Historical information

A bridge is marked at this location on the 1834 OS 6” map. The 1836 Ordnance Survey Memoir describes it as a “plain rough structure of unhewn stone with parapets 18ft broad and 110ft long, including solid masonry, consisting of two arches”. The 1862 OS map also notes it as Causeway Water Bridge, but shows three cutwaters (implying four arches). The present single cutwater structure is probably that shown on the 1901 6” map, indicating that it is a later 19th century replacement.

Primary Sources:
1. PRONI - OS 6/3/55/1 (1834 OS map) (Down sheet 55).
2. PRONI - OS 6/3/55/2 (1862 OS map) (Down sheet 55).
3. PRONI - OS 6/3/55/3 (1901 OS map) (Down sheet 55).

Secondary Sources:
1. Day, A. Ordnance Survey Memoir of County Down Kilkeel Parish.'

Criteria for listing: architectural interest

A. Style
B. Proportion
D. Plan Form
F. Structural System

Criteria for listing: historic interest

X. Local Interest

Evaluation

Built to a high standard, this bridge is primarily of interest on account of its skewed soffit stones (it is more usual to find this with brick), and paved and stepped bed.