Car Dyke, A Roman Canal at Waterbeach

In April 1993 a section though the Roman Car Dyke (or Old Tillage) at Waterbeach (SAM 3 TL 495 645) was excavated to provide information on which to base beneficial site management. The project was funded by English Heritage and the work was completed by Cambridgeshire County Council's Archaeological Field Unit. The results of the excavation appear to support the original use of the Car Dyke as a canal (20m wide and 4 meters deep), no date for construction was recovered , however the canal was abandoned sometime during the Antonine period (AD 140-180). There was a subsequent re-use probably in the 17th Century as a drain or catch-water, which has resulted in the removal of the upper (later Roman) layers of the Dyke, leaving only the truncated fills of the Roman canal. The immediate post-Roman, Saxon and medieval history of Car Dyke are therefore unknown at this point. These surviving deposits have however produced data relating to the original construction and use of the Dyke and it appears that in addition to the 17th Century dredging there was a Roman re-cut when the Dyke's primary function changed to being used for drainage soon after its function as a canal fell into disuse. Environmental data supports this theory and the disuse of the canal. Excavation also revealed remains of the original land surface to the west of the Dyke preserved as a buried soil and showed that little now remains of the canal bank due to plough damage.