Retford Water Hardness & Quality Report (2026)

Retford (East Retford), the Bassetlaw district market town in north Nottinghamshire on the River Idle — an important staging post on the Great North Road — is supplied by Severn Trent Water from the Sherwood Sandstone Aquifer that underlies the Nottinghamshire–Lincolnshire sandstone plain. The Permo-Triassic Bunter Sandstone (Sherwood Sandstone Group) is the principal aquifer of the east Midlands sandstone belt from Nottingham north through Retford to Doncaster, a productive red sandstone carrying moderately hard groundwater enriched with calcium carbonate from the sandstone cement. Severn Trent abstracts from Sherwood Sandstone boreholes in the Bassetlaw district, distributing treated supply through the north Nottinghamshire network. At 163.5 mg/L with TDS 410.1 mg/L (ratio 2.51), Retford's supply is moderately hard — consistent with typical Sherwood Sandstone groundwater chemistry, with a moderate calcium sulphate component from Keuper Marl interbeds at depth, though less sulphate-enriched than the more Triassic-evaporite-dominant zones of west Nottinghamshire.

The Sherwood Sandstone (Triassic Bunter Sandstone) beneath the Retford–Worksop–Gainsborough corridor is a regional aquifer of the east Midlands sandstone belt — a coarse, permeable red sandstone with calcium-carbonate and some calcium-sulphate cement. Groundwater at 30–80 m depth acquires calcium bicarbonate from the sandstone cement at 155–170 mg/L in the north Nottinghamshire supply zone. The TDS of 410.1 mg/L reflects carbonate hardness supplemented by modest sulphate from minor Keuper Marl evaporite interbeds in the deeper sandstone sub-surface.

At 163.5 mg/L Retford's water is moderately hard and limescale management is a steady domestic task. Kettles benefit from descaling every four to five weeks with a citric acid tablet. Shower heads need periodic soaking in white vinegar. Washing-up liquid lathers adequately. Combi-boilers benefit from inline scale inhibitor protection. Retford's Georgian market-town character — the town hall, the canal basin and the Great North Road heritage — sits on the same Sherwood Sandstone aquifer whose mineral-rich water has characterised domestic supply across the north Nottinghamshire plain since the aquifer was first exploited.