The shallow Valley and occasional stream forming the NE boundary of the Randall Manor site has been blocked by earth dams at three points. In front of the lowest dam a lake has forms in periods of modest rainfall. A brick facing in an English Bond, 1 1/2 bricks thick, inclined at 12 deg from vertical away from the lake, rested against the last 5 meters of the earth dam. The centre of the facing has been eroded or cut down to form a vee notch.
On the SE side of the vee there was a concrete block filling a vertical slot in the brickwork. This slot extends downwards into the lake silt. When the concrete block was removed a substantial horizontal timber pipe of 0.470mm square cross section was revealed. The last 25mm of the timber had been cut down to a circular section and was enclosed by a substantial iron collar.
On the top of the timber pipe there is a circular bore hole 190mm in diameter and tapered towards to top. The remains of a wooden plug remained in the hole. This plug when pulled upwards would have regulated the flow through the pipe.
It is believed that the slot and pipe arrangement is part of a sluice for regulation the level of water in the lake.

Community Archaeologist, 2008, Excavation of the brick sluice in the Randall lower lake dam (Unpublished document). SKE30730.