Tidworth Water Hardness & Quality Report (2026)

Wessex Water supplies Tidworth, the garrison town straddling the Wiltshire–Hampshire border on the eastern edge of Salisbury Plain — one of Britain's most enduring military communities, home to Tidworth Barracks (the largest Army garrison in the UK), set in the open chalk downland traversed by the upper River Bourne — from Salisbury Plain Chalk boreholes in the upper Wiltshire supply zone, treated at Heytesbury Water Treatment Works in the Wylye Valley. At 195.5 mg/L (13.7°Clark), Tidworth's water is hard — consistent with the productive Upper Chalk (Cretaceous) aquifer of the Salisbury Plain that provides moderately hard calcium bicarbonate groundwater to the plain's garrison and rural communities.

Tidworth lies on the open Salisbury Plain where the Cretaceous Upper Chalk forms a freely drained, shallow aquifer recharged by the extensive downland grassland above. Wessex Water draws on chalk boreholes in the upper Wiltshire supply zone, extracting moderately mineralised chalk groundwater to deliver 195.5 mg/L with TDS 482.3 mg/L — hard water consistent with the central Wiltshire and eastern Salisbury Plain chalk supply tier from Amesbury and Durrington through Tidworth to Ludgershall, all in the Wessex Water Wiltshire chalk distribution zone.

At 195.5 mg/L, limescale is a consistent household challenge in Tidworth. Kettles benefit from descaling every three to four weeks. The combi-boiler should be fitted with a scale inhibitor and serviced annually. 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 Salisbury Plain chalk supply at Tidworth is as fundamental a domestic feature of garrison life as the parade ground and barrack blocks that define this Wiltshire Army community.