Report on a fluxgate gradiometer survey, conducted to inform the proposed construction of a new water pipeline, running between the Glentham Pumping Station and Harpswell Reservoir. The survey investigated only part of the proposed route, running from Glentworth House Farm to the eastern side of Caenby Corner. The remains of a probable prehistoric barrow was identified as a circular magnetic anomaly, with an adjacent linear magnetic anomaly thought to represent the remains of a possibly associated ditch. Additional magnetic anomalies, thought to represent further ditches and possible ring features or pits of unknown date were also recorded to the west of the A15 road.