Thornbury Water Hardness & Quality Report (2026)
Water Hardness
~200–300 mg/L
Hardestimated · not lab-verified
Source
mixed
pH Level
8.1
neutral = 7.0
Lead
0.001 mg/L
✓ Below action level
TDS
438.9 mg/L
Est. Daily Cost
£0.57
energy & soap waste
Source: DWI Data Portal · Updated 2026
0–99
mg/L
Soft
100–149
mg/L
Slightly Hard
150–199
mg/L
Moderately Hard
200–300
mg/L
Hard
300+
mg/L
Very Hard
Appliance Damage Report
In Thornbury, your appliances are currently losing 33% efficiency due to mineral buildup.
| Appliance | In Thornbury | Soft Water City | Efficiency Loss |
|---|---|---|---|
| Kettle | 5.7 yrs | 8.5 yrs | -33% |
| Washing Machine | 8 yrs | 12 yrs | -33% |
| Water Heater | 10 yrs | 15 yrs | -33% |
Regional Water Comparison
How Thornbury compares to its nearest neighbours
| City | Hardness | Clark° | Risk | Source |
|---|---|---|---|---|
| ▶ Thornbury, South West | ≈ 200–300 mg/L | 17.5° | 🟠 Hard | mixed |
| Stoke Gifford, South West | ≈ 0–100 mg/L | 9.5° | 🟢 Soft | mixed |
| Mangotsfield, South West | ≈ 100–150 mg/L | 13.9° | 🟡 Slightly Hard | mixed |
| Yate, South West | ≈ 100–150 mg/L | 16.3° | 🟡 Slightly Hard | mixed |
| Kingswood, South West | ≈ 200–300 mg/L | 12.8° | 🟠 Hard | mixed |
National Benchmark
How Thornbury compares to the United Kingdom average
| Benchmark | Hardness | Appliance Risk |
|---|---|---|
| ▶ Thornbury | ≈ 200–300 mg/L | 🟠 High |
| United Kingdom National Avg | 177 mg/L | 🟡 Moderate |
| Skipton Top Rated | 7.1 mg/L | 🟢 None |
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What Makes Thornbury's Water Unique?
Local geology and source profile
The water supply for Thornbury is managed by Bristol Water. While specific details for Thornbury are unavailable, the utility draws water from a blend of the River Avon and springs originating in the Mendip Hills. This water is then treated at the Purton Water Treatment Works before being distributed to customers. Official reports confirming the exact source or treatment specifics for Thornbury residents were not accessible through public searches.
Thornbury's water originates from a geological area characterized by limestone, specifically springs from the Mendip Hills. This type of bedrock, primarily limestone, is known to leach minerals like calcium and magnesium into the water as it flows through underground aquifers. The presence of these dissolved minerals is what defines water hardness. The specific geological formations in the wider South Gloucestershire supply zone contribute to this characteristic.
Homeowners in Thornbury might notice the effects of hard water on their appliances and plumbing. Mineral buildup, or scale, can form inside pipes and on heating elements in water heaters and dishwashers, potentially reducing their efficiency and lifespan. Soap and detergents may also lather less effectively in harder water. To combat scale, regular descaling of appliances is recommended. If you're experiencing significant issues, a water softener might be a worthwhile investment for your home.
Geology & Source: Limestone; limestone springs produce hard water
Other South West Water Reports
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