Tap water in CF15, CardiffSafe to drink.
Supplied by Dŵr Cymru Welsh Water. 590 samples, 23 substances, latest on 19 December 2024. Everything is inside the legal limit, and nothing comes close to it.
9.4 / 10
The tank is as full as the score.
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What's in a glass of CF15 water
Every bubble is a substance the lab measured. The higher it floats, the closer it came to its legal limit, the dashed line at the top.
Trihalomethanes came closest to a limit, at 39% of it. 19 of 20 substances used under a quarter of theirs.
- Trihalomethanes39%
- Iron24%
- Colour23%
- Nickel18%
- Fluoride7%
- Turbidity7%
- Nitrate5%
- Mercury4%
- Chromium3%
- Copper3%
- Boron3%
- Nitrite3%
- Aluminium3%
- Arsenic2%
- Lead2%
- Manganese1%
- Antimony<1%
- Selenium<1%
- Cadmium<1%
- Bromate<1%
- Conductivity 92 µS/cm
- Coliform Bacteria none found
- E. coli none found
All 23 results as a table
| Substance | Result | Legal limit | Share of limit |
|---|---|---|---|
| Trihalomethanes | 0.039 mg/L | 0.1 mg/L | 39% |
| Bromate | 3.1e-7 mg/L | 0.01 mg/L | <1% |
| Boron | 0.028 mg/L | 1 mg/L | 3% |
| Conductivity | 92 µS/cm | No legal limit | – |
| Selenium | 0.00023 mg/L | 0.04 mg/L | <1% |
| Coliform Bacteria | 0 count/100ml | Must be zero | None found |
| E. coli | 0 count/100ml | Must be zero | None found |
| Antimony | 0.000046 mg/L | 0.005 mg/L | <1% |
| Lead | 0.00016 mg/L | 0.01 mg/L | 2% |
| Nickel | 0.0036 mg/L | 0.02 mg/L | 18% |
| Chromium | 0.0015 mg/L | 0.05 mg/L | 3% |
| Mercury | 0.000042 mg/L | 0.001 mg/L | 4% |
| Cadmium | 0.000025 mg/L | 0.005 mg/L | <1% |
| Arsenic | 0.00017 mg/L | 0.01 mg/L | 2% |
| Manganese | 0.00068 mg/L | 0.05 mg/L | 1% |
| Fluoride | 0.11 mg/L | 1.5 mg/L | 7% |
| Copper | 0.058 mg/L | 2 mg/L | 3% |
| Aluminium | 0.005 mg/L | 0.2 mg/L | 3% |
| Iron | 0.047 mg/L | 0.2 mg/L | 24% |
| Nitrite | 0.013 mg/L | 0.5 mg/L | 3% |
| Nitrate | 2.61 mg/L | 50 mg/L | 5% |
| Colour | 4.6 mg/L Pt/Co | 20 mg/L Pt/Co | 23% |
| Turbidity | 0.27 NTU | 4 NTU | 7% |
CF15 in short
Tap water in CF15 (Cardiff) is supplied by Dŵr Cymru Welsh Water in the Cardiff Central zone and scores 9.4 out of 10, against an England and Wales average of 9.0. None of the 23 tested substances came close to a limit. The latest sample is from 19 December 2024.
- 5th cleanest of 9 areas tested in CardiffSquarely mid-table for Cardiff, between CF30 on 10 and CF24 on 9.3. Every area in Cardiff
- Nothing tested came within 40% of its legal limitThe highest was Trihalomethanes at 39% of the 0.1 mg/L maximum. See every reading
- Scores higher than 1 of 8 neighbouring districtsWater here is typical for the immediate area, which usually means the same treatment works and the same supply zone.
Questions about CF15 water
Is CF15 tap water safe to drink?
Based on the latest tests, CF15 (Cardiff) water scores 9.4/10, which is safe. 0 of 23 tested contaminants exceeded recommended levels. Water is supplied by Dŵr Cymru Welsh Water.
What contaminants are in CF15 water?
We tested 23 contaminants in CF15 water. None exceeded recommended safe levels.
Who supplies water in CF15?
CF15 (Cardiff) is supplied by Dŵr Cymru Welsh Water. You can view their full profile and compliance data on our supplier page.
Should I use a water filter in CF15?
CF15 water scored 9.4/10 with no contaminants above recommended levels. A filter is optional but can improve taste, especially if you notice a chlorine flavour. See our filter recommendations for your area.
Are there PFAS forever chemicals in CF15 water?
No PFAS (forever chemicals) result is attached to the tap-water tests for CF15, and the Environment Agency has no PFAS detections in rivers or groundwater within 10 km of it. That reflects where sampling has happened as much as the water itself.
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