Claverton Pumping Station

Claverton Pumping Station

This Grade I listed pumping station was designed by John Rennie for the Kennet and Avon Canal Company and opened in 1813. The building has undergone mid to late 19th-century and 20th-century modifications.

The station is constructed of ashlar Bath stone with cast-iron machinery, including a waterwheel with iron and timber fittings. Smaller plant components have been replaced at regular intervals throughout its operational lifespan. Some fittings, such as filter grilles, are wrought iron. The base of the water wheel has been repaired in concrete. The roofs are of oak and covered in slate.

The principal structure is a rectangular engine house built on a former mill site beside the west bank of the River Avon, with a millpond to the west. A railway embankment lies further west, beneath which water pipes from the pumps feed the canal. Attached to the east, spanning the mill race, is a roughly square wheel house. The engine house is arranged as three storeys at the south end and two storeys at the north. Ground-floor doors open from the end elevations, and a second-floor door is located on the west flank.

The pump engine house features finely-tooled ashlar elevations beneath a hipped roof. Ground-floor openings are round-arched, while upper-floor openings have casement windows with square heads. The south elevation faces the mill pond and has a plank door with strap hinges at ground level and a casement above. The west elevation contains three ground-floor openings, with the right opening featuring an altered cill and an extruding pump outflow pipe leading to an engineering brick opening in the railway embankment. Upper-floor casements are present, along with an inserted door served by a 20th-century steel staircase and platform with an infilled area below. Modern steel stairs serve the ground floor. The north elevation has a plank door to the right and a window to the left. The hipped roof is topped with an ashlar stack.

The attached wheel house to the east has ashlar elevations with three round-arched openings fitted with timber braced and ledged plank doors. The central opening has double-leaf doors of slightly lower height than those to either side. The north and south elevations are weatherboarded with two casements to the north. The wide pitched roof is slate-covered with engineering brick repairs below the eaves. To the south, the lower section of the east wall extends to form a cutwater and sluice, connected to filter grilles that traverse the millpond at the southern approach to the mill wheel, with a central stone cutwater. To the north, lower walls extend to form pound walls with coping stones. The east wall terminates in an ashlar flood arch facing north. The west wall extends further in random rubblestone with copings.

The ground floor of the engine house is accessed from the north door via three stone steps descending to the pit wheel room. This rectangular double-height space contains the pit wheel set within its pit, mounted with cast-iron gear on a shaft fitted with overhung cranks and flywheel. Connecting rods attached to the crankpin link to two 18 feet 6 inches Boulton & Watt steam engine type beams located in the room above. The rods pass through openings in the upper floor structure, which is formed of large-scantling oak beams and joists with an inserted I-beam dated 1888. A lateral stone engine wall spans the room at the south end with an arched opening to the pumps. Fixed above this arch is a mid-19th-century foundry pattern used for casting the central bearing to the waterwheel. A cast-iron half-wheel from 1810 to 1813, formerly part of the waterwheel, is mounted on the west wall. Whitewashed walls are incised at intervals with dated inscriptions marking flood water levels. Three openings in the east wall connect to the wheelhouse. Floors are laid with diamond setts.

Beyond the arch in the lateral wall lies the pump room containing two pumps, each with a pump rod and Watt linkage above connecting to the south end of each Boulton & Watt beam. An 1840s piston head is located in a corner of the room. The room's roof has been adapted with late-19th-century steel beams. A pump inlet valve below water level is positioned in the east wall. A timber stairway accesses a floor above with the Watt linkage, which has attached 20th-century safety modifications. The pump outlet exits the building through the base of a west wall opening. A further flight of stairs leads to the upper floor at beam level, which features an exposed king-post oak truss roof. A separate mess room at the north end of the floor contains a stone fireplace with cast-iron stove.

The wheelhouse contains a wide-span arch-braced oak roof with some adaptations including iron strap strengthening. A timber plank floor runs alongside the water wheel on three sides. The waterwheel is constructed in two sections from 12 cast-iron half-wheels bolted together and secured on an axle shaft with wedges. The shaft runs in three gun metal bearings, and the wheel rims have modern timber starts, float and seal boards. Within a plank platform set by the south wall are the upper mechanisms to four control depressing sluices below. The elm depressing sluices were repaired in the mid-20th century and given concrete replacement lower members. The waterwheel connects to the pit wheel by a semi-flexible coupling.