Monument MPM1685 - Sluices, King's Mill

The remains of abutments to the sluices which regulated the flow of water to the tidal King's Mill observed during an archaeological evaluation at the Gunwharf Quays site in 1997. Sluices for two waterwheels would have been positioned either side of a central tidal sluice.

The remains of stone and brick abutments to the sluices which regulated the flow of water to the King's Mill (see MPM1013) were observed during an archaeological evaluation at the Gunwharf Quays site in 1997. Sluices for two waterwheels would have been positioned either side of a central tidal sluice, with iron guards fixed across the entrances to prevent refuse from entering. The sluice walls may originally have been constructed from stone and were later re-built in brick. The floors of two of the sluices appear to have been made using rectangular stone slabs.

The remains of four masonry walls constructed of limestone blocks and red bricks were revealed within 45cms of the present ground surface. These walls would have formed the east abutments of the three sluices which served the King's Mill. Due to the mixture of materials used in their construction, it is likely the walls had been altered and repaired over a long period of time. The central sluice had vertical sides and measured 3.82m wide at the top. Brick-faced walls approximately 1.52m wide were positioned between the central and two side sluices. The north wall of the northernmost sluice may originally have been constructed from stone, and subsequently re-built in brick on two occasions. During the last phase of re-building stone quoins (corner stones) were incorporated at the north-east corner of the sluices. An iron refuse guard had been fixed to the east face of the north-east quoin. The guard was formed from a curved iron band 11cms wide and 2cms thick, to the underside of which 3.5cm square rods had been fixed at a 45 degree angle. This gaurd was intended to stop refuse entering the mill sluice, and would probably have been semi-circular, the other end of the band being fixed to the next wall along. The corner of the south-east side of the sluices was of similar construction, with brickwork and stone quoins. An identical refuse guard had been attached to the east face. It was not possible to ascertain the construction of the two intervening walls as the east ends were not exposed, but they were probably of similar form to the north and south walls. It is not known whether the central sluice had a refuse guard.

Stone floors which formed the base of the central and south sluices were encountered 3.86m and 3.76m respectively below present ground level. The floors could not be examined in detail, but appeared to have been constructed using rectangular stone slabs. The brickwork which formed the sides of the sluices appeared to continue vertically to the floor level. The sluices themselves may have been destroyed by the construction of a surface water sewer during the 1890s.

Accession No: 2013/112

The Conservation Practice, 1997, Gunwharf Quays, Portsmouth, An Archaeological Evaluation. Part Two: Site Investigation (Unpublished document). SPM326.