Matlock Water Hardness & Quality Report (2026)

Severn Trent Water supplies Matlock, the administrative centre of Derbyshire Dales in the Peak District at the junction of the Derwent Valley with the White Peak limestone plateau, from the Derwent Valley Reservoirs — Howden, Derwent, and Ladybower — blended with spring and borehole water from the Derbyshire Carboniferous Limestone (Dinantian), treated at Bamford Water Treatment Works in the upper Derwent Valley. At 166.5 mg/L (11.7°Clark), Matlock's water is moderately hard, reflecting the prominent influence of the White Peak limestone that envelops Matlock on three sides.

Matlock sits at the dramatic gorge where the River Derwent cuts through the Carboniferous Limestone reef knolls and scarp of the White Peak — the same Dinantian limestone that has created the Peak Cavern, Treak Cliff Cavern, and the Via Gellia limestone dales. The White Peak Limestone is among the most soluble bedrock types in England, producing hard calcium-rich spring water throughout the Derbyshire Dales. This limestone spring water blends with the soft Derwent Valley Reservoir baseline supply at Bamford works to produce the moderately hard 166.5 mg/L supply at Matlock, with TDS 433.4 mg/L reflecting the calcium bicarbonate character of the limestone springs.

At 166.5 mg/L, limescale is a noticeable domestic concern in Matlock. Kettles benefit from descaling every four to six weeks. The combi-boiler should be fitted with a scale inhibitor and serviced annually. Washing-up liquid requires slightly more product than in softer areas. Taps and shower heads develop moderate limescale deposits within two to three weeks; a monthly wipe with white vinegar keeps fixtures in good condition. The moderately hard limestone-influenced supply is characteristic of the beautiful Peak District limestone dales surrounding Matlock.