Loading water report
Fetching the latest data for this area
South Oxfordshire, England
Your water in RG4
South Oxfordshire
Your water is safe
We checked 22 things and found 2 worth knowing about
GoodYour water is safe
We checked 22 things and found 2 worth knowing about
GoodH
Water hardness: 316 mg/L (very hard)
Hard water — may cause limescale buildup in kettles and pipes
Hard water is costing your home money
Your water is very hard (316 mg/L) — find out if a softener is worth it
Tap water in RG4 (South Oxfordshire, South Oxfordshire) is supplied by Thames Water and scored 8.7 out of 10 for safety based on 22 tested parameters. 2 contaminants exceeded recommended safe levels: Nitrate, Nitrite. Data is from 71 samples collected up to 2025-12-31, sourced from Thames Water via the Stream Water Data Portal.
Drinking water testsHow we score
Last sampled 2025-12-31 · 71 samples
What’s in your tap water
Results from drinking water tests in South Oxfordshire.
What removes these from your water
2 contaminants flagged in RG4. These filters are matched to what was found in your water.
Our pick for RG4
Waterdrop G3P600 Reverse Osmosis
Reverse Osmosis · NSF/ANSI 58, NSF/ANSI 372
The Waterdrop G3P600 Reverse Osmosis is certified to remove Nitrate, which was flagged in RG4. Fits under your kitchen sink for filtered water on tap.
Removes from your water
Nitrate
Check price & reviews
£399
4.6/5
2 more options
Recommendations matched to your area's water data, not sponsorship. We may earn a commission at no extra cost to you. Affiliate disclosure · Full filter guide
Hard water is costing your home money
Limescale reduces boiler efficiency and shortens appliance life. Based on your water hardness (316 mg/L — very hard), a softener could save you £200+/year.
Get a free assessment — we'll tell you if it's worth it and connect you with trusted local installers.
100%
free, no obligation
vetted installers
24h
response time
Shower filters
Remove chlorine for better skin and hair
Test your water
Confirm exactly what's in your pipes
Related guides
Learn more about the water quality issues relevant to this area.
Environmental water nearby
Rivers, groundwater and reservoirs near RG4. This is environmental monitoring — not your tap water.
| Substance | Found | Safe Level | WHO Safe Level | Status |
|---|---|---|---|---|
| pH | 8.4 pH | — | — | Safe |
| Temperature | 7.62 °C | — | — | Safe |
| Ammonia | 0.03 mg/L | 0.5 mg/L | — | Safe |
| Nitrate | 5.27 mg/L | 50 mg/L | 50 mg/L | Safe |
| Phosphate | 0.191 mg/L | — | — | Safe |
| Dissolved Oxygen | 12 mg/L | — | — | Safe |
Source: Environment Agency
Learn more
Get alerts for your area
We'll email you when water quality data changes for RG4.