South West Water has begun work on projects designed to improve drinking water in Devon and Cornwall, with a combined investment of more than £11m in two of its water treatment facilities.An investment of £6.3m will be made at Northcombe Water Treatment Works to six new granulator activated carbon filters.The facility is the company’s fifth largest water treatment works and supplies large areas of North Devon including Barnstaple, Bideford and Torrington.Meanwhile, £5.5m will be spent at Tamar Lakes Water Treatment Works, near Holsworthy, to install additional manganese removal filters, five new granulator activated carbon filters and a state-of-the-art ultraviolet disinfection system.The site supplies Bude and the surrounding villages along that stretch of the Atlantic Highway.