Throop Mill Sluice Gates

Reasons for Designation

The sluice gates at Throop Mill are designated at Grade II for the following principal reasons: * Despite the mid-C20 date of the machinery, the structure is remarkably complete and an increasingly rare survival of its type * Architectural quality is demonstrated in the masonry parts * They are a significant component of, and integral part of the water control system for Throop Mill * Form a strong functional and visual group with the Grade II listed mill and contributing significantly to the character of the area

Details

HURN

748/0/10031 THROOP 06-JUN-08 Throop Mill Sluice Gates

GV II

Sluice gates, flanking aprons and piers. C19 with earlier origins. Gates and lifting mechanisms replaced in the first half of the C20.

MATERIALS: Masonry aprons and piers with cast-iron gates and lifting mechanisms.

EXTERIOR: The superstructure is built of cut and coursed stone. It comprises the flanking aprons and the five piers that define the hatches within the channel. The piers have buttressed cutwaters on the lower (east) side and pointed ones on the upper side. The piers and northern abutment define the hatches in which the sluice gates are positioned. The sluice gates were replaced in the mid-C20. There are six in total, located within the hatches, each retaining two horizontal plates which are fixed to the flanking piers. The hand-operated lifting mechanisms, including wheeled ratchets and vertical shafts, also survive. At the southern end is a fish pass, erected to prevent the obstruction of fish by the sluice gates. It is of concrete and appears to date from the late-C20 and is of lesser interest. The piers also support a concrete and metal footbridge on the west side of the sluice gates which replaced an earlier timber footbridge and this is not of special interest.

HISTORY: A mill is recorded in this parish (formerly Holdenhurst in Hampshire) in the Domesday Book though it is unclear whether it was in this location or near to the site of the present mill building, though the foundations of an earlier building have been discovered in the existing mill. Throop Mill is documented from the late-C18. The current building dates from the late-C19 and was driven by a 50" turbine made by Armfields, a local Ringwood firm. Although now disused, it retains its early-C20 milling machinery. The sluice gates were installed to regulate the flow of water to the mill, acting as a by-pass to divert excess water from the mill race into an overflow channel which rejoins the river to the north east of Throop Mill. The ashlar abutments and piers that form the basic structure of the sluice are shown on the first edition (1883) Ordnance Survey map and their form has changed little since. It is likely that the structure has earlier origins. The sluice gates themselves and their lifting mechanisms were replaced in the mid-C20: the three forming the southern half of the structure were manufactured by the Dorset Iron Foundry Company in Poole; the northern three are by Lott & Warne Ltd of Dorchester (1899-1956), who were iron founders and agricultural engineers. A stamp on each of the three northern sluice gates indicates that these were replaced by the Avon and Stour Catchment Board in the 1936. Throop Mill appears to have undergone a period of modernisation and upgrading in the first half of the C20; new equipment was installed in phases between c. 1926 and the late 1930s, and at the same time the sluice gates were also renewed. The mill ceased operating in 1974; and the sluice gates are no longer operational.

SOURCES: M. Watts, Throop Mill, Bournemouth, Dorset (2008), unpublished

REASON FOR DESIGNATION DECISION: The sluice gates at Throop Mill are listed at Grade II for the following principal reasons: * Despite the mid-C20 date of the machinery, the structure is remarkably complete and an increasingly rare survival of its type * Architectural quality is demonstrated in the masonry parts * They are a significant component of, and integral part of the water control system for Throop Mill * Form a strong functional and visual group with the Grade II listed mill and contributing significantly to the character of the area

Legacy

The contents of this record have been generated from a legacy data system.

Legacy System number:

504973

Legacy System:

LBS

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