 The Lark Engine pumping station was upgraded again in 1974.The Blackstone engine was retired but kept intact as part of the history of the district, the Crossley engine became the standby, and the Crossley enginehouse was extended to allow the installation of a Dorman Diesel engine, which drives a Allen Gwynne vertical spindle pump.The work included the provision of a wooden plaque, showing all of the engines which had been installed since the opening of the station in 1842, which was unveiled by Mrs F. G. Starling at the formal opening held on 25 May 1976.