Loughborough Water Hardness & Quality Report (2026)

Loughborough, the north Leicestershire market town and university town on the River Soar, is supplied by Severn Trent Water from the Derwent Valley Reservoir system and local East Midlands groundwater sources. Severn Trent's primary supply for north Leicestershire and the Soar valley draws from the Ladybower, Derwent, and Howden reservoirs in the Peak District — the famous Derbyshire Derwent valley dams — supplemented with groundwater from the Triassic Sherwood Sandstone Aquifer beneath the Leicestershire plain and Jurassic Lias limestone and clay formations in the Soar valley. The Derwent reservoirs are soft-water upland sources, but the local Triassic sandstone and Jurassic Lias groundwater — both more mineralised — raise the blended supply hardness to hard values at Loughborough.

Loughborough's hardness of 225 mg/L (15.8°Clark) reflects the Triassic Sherwood Sandstone and Jurassic Lias groundwater contribution in the north Leicestershire supply zone. The Triassic geology beneath north Leicestershire — Mercia Mudstone (Keuper Marl) and Sherwood Sandstone — yields groundwater with moderate to high dissolved calcium and sulphate from mudstone and evaporite mineral dissolution. The Jurassic Lias of the Soar valley contributes further calcium from Liassic limestone dissolution. The combined blend places Loughborough firmly in the hard range of the Drinking Water Inspectorate (DWI) classification.

Limescale is a persistent household challenge in Loughborough. At 225 mg/L, limescale forms in kettles within two to three weeks and monthly or fortnightly descaling is advisable. Combi-boiler heat exchangers accumulate deposits steadily — annual boiler servicing and fitting an in-line scale inhibitor are strongly recommended. Showerheads, taps, and shower screens develop regular deposits. Washing-up liquid lathers poorly. Using Calgon monthly in the washing machine and maintaining a regular descaling routine is important limescale management for Loughborough households.