Chatteris Water Hardness & Quality Report (2026)

Anglian Water supplies Chatteris, the Cambridgeshire Fenland town at the heart of the flat Isle of Ely — a traditional Fenland market town surrounded by the rich black peat farmland of the South Level Fens, with a Tuesday market at the town centre, medieval drainage dykes running through the surrounding fields, and a setting that exemplifies the transformed fen landscape of Cambridgeshire — from the East Anglian Chalk aquifer and Great Ouse regulated river supply in the Cambridgeshire Fenland distribution zone, treated at Grafham Water Treatment Works near Huntingdon. At 240.5 mg/L (16.9°Clark), Chatteris's water is hard — consistent with the Cretaceous Chalk aquifer supply characteristic of the Anglian Water east Cambridgeshire and Fenland distribution zone.

Chatteris lies in the South Level Fens of Cambridgeshire where Anglian Water draws from the East Anglian Chalk boreholes and the regulated Great Ouse at Grafham Water reservoir. The Chalk aquifer beneath the Fens delivers calcium carbonate groundwater, producing 240.5 mg/L with TDS 631 mg/L — hard water with a moderate TDS/hardness ratio (2.62) consistent with the Cambridgeshire Fenland chalk supply zone at March (241 mg/L) and Ely (239 mg/L) in the same Anglian Water Fenland distribution corridor.

At 240.5 mg/L, limescale is a persistent household challenge in Chatteris. Kettles should be descaled monthly. The combi-boiler benefits from a fitted scale inhibitor and annual professional servicing. Washing-up liquid requires more product per wash. Taps and shower heads develop visible white limescale deposits within one to two weeks; a fortnightly wipe with white vinegar or a proprietary descaling product keeps fittings clean. The hard chalk supply at Chatteris is characteristic of the Cambridgeshire Fens — the great East Anglian Chalk aquifer running beneath the peat fields delivering mineralised groundwater to Fenland households just as the drainage engineers once channelled the floodwaters into the Great Ouse.