South West Water has opened a £5.5million upgrade to works in North Cornwall to treat naturally occurring manganese and provide better disinfection.

Tamar Lakes water treatment works (WTW) supplies the holiday resort of Bude and surrounding villages. With the fluctuating population, it produces around five megalitres of water a day (Ml/d) during the winter and up to 8 Ml/d in summer.

The WTW now has additional manganese removal filters, five new granular activated carbon (GAC) filters and a state-of-the-art ultraviolet (UV) disinfection system.

A spokesperson for the company said: "Manganese, which occurs naturally in reservoirs, can occasionally reach levels that may cause discolouration within the water network so it is important we improve the treatment to remove manganese to ensure the appearance of our water to customers is consistently good."

GAC is a specially engineered and extremely porous material with a large internal surface area – just one teaspoon has the same surface area as a football pitch. Due to its large surface area and special surface chemistry it can remove natural and manmade organic matter sometimes present in Tamar Lakes reservoir, which supplies the WTW.

UV disinfection uses ultraviolet light to destroy harmful bacteria and viruses sometimes found in the untreated reservoir water.

The company previously successfully used the same approach at Restormel and Wendron WTW in Cornwall.