2011:178 - BALLYDOWD/LUCAN, Dublin

The Dublin Region Watermain Rehabilitation Project is an initiative intended to tackle the high level of water leakage from within the water distribution network. The project will seek to identify those areas of watermain infrastructure yielding the greatest sustainable water savings throughout the Greater Dublin Region (GDR). The GDR for the purposes of the project consists of the county council areas of Dublin City, Fingal, South Dublin, Dun Laoghaire–Rathdown and parts of Kildare and Wicklow. To date, the project has recommended mains in 55 DMAs for rehabilitation.
On the basis of the techniques which were to be used, a series of five scenarios for determining the level of monitoring were agreed with the City Archaeologist and the National Monuments Service. In March 2009 these scenarios were reviewed and amended on the basis of the results of the monitoring on this project to date. As a result of this review, only two scenarios necessitated archaeological attendance. In Scenario 1, where open-cut trench excavation is carried out within 30m of RMP/within ZAP, full-time monitoring is required if there is no existing main within the trench; intermittent monitoring is required where the trench is excavated over an existing main. The second scenario requiring monitoring is Scenario 5: where any excavation technique is to be used within 10m of a National Monument, full-time monitoring is required.
There are two monuments within the Ballydowd DMA. A holy well (DU017-017) and a castle site (DU017-018) are located to the north of the village centre. The village of Lucan itself is classed as a zone of archaeological potential (DU017-019). The area that was to be subjected to watermains rehabilitation included the ZAP of Lucan village.
While a licence had been issued for monitoring in 2010, the bulk of the groundworks associated with the DMA were not carried out until 2011. Therefore an extension to the licence was granted in March 2011. Monitoring of works in this DMA was carried out on occasions between May and June 2011. The works that formed part of the Ballydowd DMA consisted of monitoring of open-cut trenching on Main Street in Lucan.
The process of rehabilitation involved either the exposure of the existing watermain or the excavation of a new trench for a new pipe (new-lay). This was generally carried out with the use of a mechanical excavator of either JCB type or a smaller ‘mini-digger’ type. Where necessary, some of the trenches were also excavated by hand.
The excavated trenches measured approximately 0.5m in width and ranged from approximately 0.6m to 1.2m in depth. In some cases larger areas were opened to expose the junction between a number of watermains. Following the removal of the upper surface of tarmac, the underlying hardcore/sand was removed. Below this the entire trenches were backfilled with modern deposits containing modern ceramics and building waste. No archaeological features, deposits or artefacts were revealed during monitoring of these groundworks.

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