Report on an archaeological watching brief, conducted during groundworks for the installation of a new water mains pipe between the villages of North Thoresby and Tetney. The groundworks exposed the remains of a number of likely late post-medieval and modern drainage and boundary ditches, along with a further ditch of probable archaeological origin. This feature clearly pre-dated the establishment of North Thoresby village in this area, and it was thought possible that it may be of Iron Age or Roman date. No associated artefacts were recovered from the fill of the feature, however, and its exact origins could not therefore be determined.