Wessex Water is installing Rotork intelligent electric valve actuators throughout a GBP 25 million project to improve the quality of water supplied to over 200,000 customers in central Somerset, UK. Maundown water treatment plant was built in the 1960s and was first extended in the early 1970s. The site, which treats water from Wimbleball and Clatworthy reservoirs, is now being entirely redeveloped to further improve the quality of drinking water, upgrade the water treatment facilities and meet increased peak demand for water in the area. Under PLC control, Profibus-enabled Rotork IQ and IQT electric actuators will operate penstocks and butterfly valves to control the flow of water and sequential backwashing operations throughout the new treatment plant, comprising raw water screening, dissolved air flotation, rapid gravity filtration and granular activated carbon treatment followed by chlorine contact tanks. As well as increasing the treatment capacity to 82.4Ml/D, the improved treatment processes will overcome taste and odour problems caused by increased algal blooms in the local water sources resulting from changing weather patterns. The new building has been designed with a sedum (green) roof, providing all-year-round insulation and a natural habitat for wildlife, as well as helping the site to blend into its rural surroundings. All the water from the roof is collected with the site’s surface water and stored in a dirty wash water tank, from where it is channelled into the head of the treatment works. Rotork has supplied more than 200 actuators for the Maundown project, which has the support of the Government’s Drinking Water Inspectorate and is due to be completed by the end of 2008.
