Huntingdon Water Hardness & Quality Report (2026)

Huntingdon, the Cambridgeshire market town on the Great Ouse — the birthplace of Oliver Cromwell — is supplied by Anglian Water from Grafham Water, the large reservoir impounded from the River Ivel (Great Ouse tributary) in south Cambridgeshire, and from Cambridgeshire Chalk Aquifer boreholes in the surrounding chalk country. Grafham Water stores chalk-influenced Ouse valley water drawn from the chalk catchments of Bedfordshire and Cambridgeshire; its inlet water is already moderately hard from the chalk-draining tributaries of the Great Ouse. In addition, Anglian Water operates chalk borehole abstracttion across the Cambridgeshire chalk dip slope, contributing concentrated chalk groundwater at 280–300 mg/L to the supply blend. Water is treated at Grafham Water Treatment Works before distribution to Huntingdon. At 283 mg/L Huntingdon's supply is very hard — harder than nearby Saint Neots (258 mg/L, batch 22) upstream on the Ouse, reflecting a higher proportion of chalk borehole water in the Huntingdon supply blend.

The Cretaceous Chalk of Cambridgeshire dips east beneath London Clay and glacial drift, becoming increasingly confined east of the Ouse valley. In the Grafham Water catchment and the Huntingdon area chalk, unconfined to semi-confined groundwater at 40–80 m depth achieves calcium bicarbonate concentrations of 270–290 mg/L — slightly more concentrated than at Saint Neots further west, where greater Great Ouse surface-water dilution moderates the hardness. The TDS of 815.9 mg/L reflects chalk carbonate chemistry with elevated sulphate from the Gault Clay and Greensand above the chalk that contribute to the Cambridgeshire chalk supply mineral profile.

At 283 mg/L Huntingdon's water is very hard. Kettle elements fur rapidly and require fortnightly descaling with concentrated citric acid. Shower screens develop a persistent calcium crust without weekly chemical limescale treatment. Washing-up liquid consumption is elevated. Combi-boilers need inline magnetic scale inhibitors and annual servicing to remain efficient. Huntingdon's graceful stone market town character on the Ouse meadows belies the very hard Cambridgeshire chalk water that challenges every household appliance — the same chalk downland that frames Huntingdon's pleasant landscape also drives its domestic limescale problem.