Water hardness in Sunderland (North East England): 12.3°fH, quality index 8/10. Official UK data.
✓ Compliant with DWI standardsSunderland has soft water (12.3°fH). Low limescale risk: descale appliances every 3 to 4 months as a precaution.
UK tap water is subject to the Water Supply (Water Quality) Regulations 2018, overseen by the Drinking Water Inspectorate (DWI). The sanitary compliance indicator shows whether the latest official analyses found any non-conformities on parameters such as bacteriology, nitrates, pesticides or heavy metals.
The TH (Total Hardness) measures calcium and magnesium content. Below 10°fH: soft. From 10 to 20: moderately soft. From 20 to 27: slightly hard. From 27 to 35: hard. Above 35: very hard. Sunderland's water is slightly hard at 12.3°fH.
Maintenance budget: ~£34/year
For 2 persons, water at 12.3°f deposits around 0.6 kg of limescale per year in your appliances. Estimated cost in descalers, salt and filters.
Calcium: ~20 mg per litre
Your water provides 20 mg of calcium/L, which is 2% of the recommended daily intake.
Filtration not required
Your soft water does not require filtration. A jug filter remains useful for taste.
The tap water hardness in Sunderland is 12.3°fH, corresponding to slightly hard water. In comparison, the England average in our dataset is 18.1°fH and the North East England region average is 6.63°fH.
Yes. The water in Sunderland meets DWI sanitary standards (Water Supply (Water Quality) Regulations 2018). The hardness of 12.3°fH affects taste and appliance maintenance, not safety. Water in Sunderland is supplied and monitored by Northumbrian Water.
At 12.3°fH, a water softener is optional in Sunderland. Regular descaling (every 1 to 3 months depending on appliance) and a pitcher filter are sufficient to limit limescale buildup.
A hardness of 12.3°fH corresponds to approximately 20 mg of calcium per litre, or 2% of the recommended daily intake. This calcium is not dangerous; hard water can even contribute to your daily calcium intake.
Water in Sunderland is supplied by Northumbrian Water. Data source: Northumbrian Water 2025.
Data: Northumbrian Water official zone-level hardness reports (2025). Values verified via DWI drinking water quality database.