2003:368 - CULMORE POINT: Culmore Water Treatment Plant, Derry

A metal-detection survey and subsequent monitoring of topsoil-stripping took place at the site of proposed wastewater treatment works at Culmore Point, Co. Derry. An impact assessment carried out previously had identified the area as being one of archaeological significance, given its proximity to the site of a 17th-century fort, and pre-development investigations were recommended. The metal-detection survey was carried out over a period of two days, while monitoring of the topsoil-stripping was carried out over a period of seven weeks.

The proposed development site is located north of Derry city, to the immediate south of the existing treatment plant. Prior to investigation, the site was within a greenfield area covered by a copse of willow trees. The field is very flat, being situated on the west shores of the River Foyle surrounded by relatively flat estuarine land, overlooking the mouth of the river.

The metal-detection survey was carried out by walking the width of the proposed development in c. 5m-wide north–south rows. Each detection hit was marked out with a flag, whereby an archaeologist excavated the topsoil around it. Where an object was uncovered, its position was surveyed into the landscape using an electronic Total Station and it was labelled accordingly.

In total, 78 artefacts were recovered from the metal detection survey. These ranged in type from metal clothes buttons to belt buckles, to fishing implements, to coins, and also a quantity of lead bullets and musket balls. As the findspots of musket balls and bullets may indicate the location of a battle within the field, the density of these finds was mapped out. Two areas of high-density findspots were identified, one in the south-east quadrant of the field, the other extending in a line north–south across the southern portion of the field. Unfortunately not a sufficient quantity of this find type was recovered to positively identify this area as being a battle site.

Topsoil-stripping was carried out using a machine fitted with a toothless bucket. The topsoil consisted of a peaty, loamy material. Subsoil within the area consisted of a number of estuarine deposits consisting of silty clays to sandy silts, to gravelly sands towards the lough edge. While a number of modern field drains were uncovered, extending across the site in a north-west/south-east direction, only one other feature of archaeological potential was uncovered during the course of this work. This was located adjacent to the northern field boundary of the site, c. 60m from the north-east corner of the field, sandwiched between layers of peaty topsoil. The feature consisted of a subcircular spread of dark-brown to black, friable peaty silt, heavily charcoal-flecked, 1m by 0.6m in size and orientated north–south. A number of small stones appeared to be delimiting the north and west edges of the spread, suggesting that it may be the remains of a stone-lined feature. Excavation of the feature revealed it to be an irregular-shaped pit, 1m by 0.7m in size and up to 0.18m deep, with gently sloping sides and a curving base. It was filled entirely by the deposit described above, while the stones noted on the surface continued to line the northern half of the feature. Many of the stones showed evidence of being burnt around their surface, suggesting that this feature represented the remains of a hearth. No artefacts were recovered from the fill of the hearth to indicate a date for its use.

During monitoring of the topsoil-stripping a number of flint flakes were recovered from within the peaty topsoil layer, concentrated within a 30m2 area within the eastern quadrant of the site, suggesting that there had been prehistoric activity within the area at some stage, although occupational remains were not detected.

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