It was originally thought that eminent engineer John Rennie constructed the waterwheel operated pump in 1808 so that water could be used to power the former Melingriffith Tinplate Works. However, extensive historical study has provided an earlier date of construction and it is also thought that it was created by Watkin George, a carpenter, engineer and ironmaster from Trevethin. George helped construct many bridges in South Wales, including Pont-y-Cafnau and the Merthyr Bridge.

Rennie’s involvement was minimal as he and fellow engineer William Jessop were consulted in 1808 to help overcome problems with the pump. The pair recommended the use of a steam engine to power the pump, rather than a water wheel, but this idea was not used as the owners of the tin plate works would not contribute to the costs of its construction.

Melingriffith Water Pump was designed to feed the water leading into the adjacent Glamorganshire Canal that would provide a water supply for the successful tin manufacturing plant. The Canal is by and large all but gone, but a small amount of it is still found just off of the River Taff in the Long Wood Nature Reserve.

In its early life the canal suffered from water shortages on its approach to Cardiff. It was decided to build a pump to transfer water from the River Taff to the canal. Situated downstream of the tinplate works, it was thought that it would not interfere with the works’ ability to take water directly from the river. The pump continued to be used until the late 1920s.

Melingriffith has been restored and can be found just off of Ty Mawr Rd, Whitchurch, Cardiff, in the north western outskirts of Cardiff, close to Junction 32 of the M4.

The pump is a scheduled monument, and now has its own conservation area, which was designated in 1975, and is designed to preserve the landmark as part of the city’s industrious heritage.

The pump consists of a paddle wheel and two rocking beams of oak, connected to vertical pumping cylinders and pistons, using chain mechanisms.

It first began to be restored in the late 1970s by the Inland Waterways Association, although the canal it fed had closed in the 1940s. The tinplate works were subsequently demolished in the 1980s and were replacing with housing.

When restoration works on the pump were finally completed in 1989, it was placed under the care of Cardiff City Council, who collaborated with the Welsh Development Agency to ensure a water supply kept running so that the water pump could still be operated. Further updates in 2009-2011 were delayed by roosting bats, but the changes meant the pump now operates via electric power and is run regularly.

Although its original purpose has now been lost, Melingriffith Water Pump remains as an active part of the city’s industrial story, and due to ongoing restoration and council’s control, is likely to exist as a working entity for many years to come.