Archaeological monitoring was carried out at 9 Prettygate Road, Colchester, Essex during groundworks for the construction of a rear extension. Located in an area of high archaeological potential, the Late Iron Age Heath Farm Dyke crosses the rear of the property. Groundworks for the new foundation trenches revealed an undated posthole and gully, with a further two features possibly associated with previously demolished conservatories. Despite being located partially within the projected route of the bank of the Heath Farm Dyke, there were no archaeological remains within the soakaway.