Cirencester Water Hardness & Quality Report (2026)

South West Water serves Cirencester, drawing its supply from a mix of sources across Devon, Cornwall, Somerset, and parts of Dorset and Wiltshire. The primary water comes from surface sources, including the River Dart, River Exe, and reservoirs like Roadford and Wistman's, all located on the granite moors of Dartmoor. This is often blended with groundwater from boreholes in East Devon's limestone regions. Treatment takes place at facilities such as the Chittering Packer works near Exeter, with additional local boosters supporting over 4 million customers throughout South West England. Cirencester itself receives this predominantly soft water, which originates from the moorland catchments.

The geology influencing Cirencester's water is diverse. The Cotswold Hills watershed features Jurassic oolitic limestone formations like the Great Oolite Group and the overlying Inferior Oolite. These permeable limestones create the Cotswold Sands and limestone aquifer. However, the regional supply heavily relies on soft, peaty surface waters from the granite catchments of Dartmoor and Exmoor. Because granite lacks significant calcareous rocks and the moorland water is acidic, there's minimal dissolution of minerals, resulting in naturally soft water.

Because the water is very soft, you're unlikely to find significant scale buildup in appliances like kettles, irons, or washing machines, which should help reduce maintenance. You won't typically see limescale deposits on taps or fixtures, helping to preserve the efficiency of your water heater and dishwasher. While soft water tends to lather soap better, some people find the feel slightly slippery. A water softener isn't necessary for this supply and could potentially remove too many beneficial minerals. The water meets UK Drinking Water Inspectorate standards, with a typical pH between 7.0 and 8.0. South West Water also ensures lead compliance through pipe replacement programs and has reported no significant PFAS exceedances.