Gloucester is supplied by Severn Trent Water. The water is moderately hard (155 mg/L CaCO₃), meaning it has moderate mineral content — some limescale buildup over time. Enter your postcode for your exact zone's full report.
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Tap water in Gloucester is provided by Severn Trent Water, which serves Gloucestershire. The water in this area is classified as moderately hard, with a typical hardness of around 155 mg/L CaCO₃. Some limescale buildup is normal, particularly on kettles and showerheads.
UK tap water is among the safest in the world, with over 99.9% of tests passing legal standards each year. However, hardness levels, trace contaminants, and the presence of disinfection byproducts like trihalomethanes (THMs) vary significantly by zone — even within the same city. That's why it's worth checking your specific postcode.
Gloucester's water hardness of approximately 155 mg/L CaCO₃ places it in the moderately hard category. Hard water is caused by chalk and limestone rock that water filters through before reaching the water table. In Gloucester, this is primarily from local geological sources.
For context, hardness below 60 mg/L is considered very soft, 60–120 is soft, 120–180 is slightly hard, 180–250 is moderately hard, 250–310 is hard, and above 310 mg/L is very hard. The UK average is around 150–200 mg/L.
UK tap water is safe to drink straight from the tap without filtration. However, at 155 mg/L CaCO₃, Gloucester's water is moderately hard — a filter or water softener can significantly improve taste, reduce limescale, and extend the life of your appliances. Reverse osmosis systems remove the widest range of contaminants including nitrates, THMs, and any trace PFAS compounds.
Enter your postcode above to see zone-specific data — hardness, nitrates, lead, chlorine, fluoride and more — directly from Severn Trent Water's annual compliance report.
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