2011:203 - DUBLIN: Chesterfield Avenue, Phoenix Park, Dublin

In October–December 2011, monitoring took place on behalf of the Office of Public Works along the line of Chesterfield Avenue in the Phoenix Park. The works consisted of the removal of the old road surface and its replacement by a new road with deeper foundation. For the most part, this involved excavating to a depth of 0.4–0.7m.

A number of drains were found. Some of these were box drains with stone sides and top. These were generally about 0.35–0.5m wide and crossed the road at right angles. They were clearly contemporary with the road, which was built in the 1840s. Most of the drains, however, ran diagonally relative to the line of the road, and evidently pre-dated it. These were narrower: 0.2–0.3m wide. They were stone-filled, like French drains, but had a small open channel running along the centre, at the base. A ditch was found on the line of the boundary between the parishes of Castleknock and St James. This had been backfilled by the early 19th century and there was no indication on the surface of its presence.

Elsewhere, an isolated concentration of mussel shells was found. It covered an area measuring 1.1m x 0.43m and was up to 0.1m deep, filling an irregular hollow. No artefacts were present.

The most important feature was the remains of the star fort shown on the pre-Ordnance Survey maps. This was investigated and is described at No. 204, Excavations 2011.

Monitoring work is to continue during 2012.