Tap water in CT4, CanterburySafe to drink.
Supplied by Southern Water. 3,472 samples, 21 substances, latest on 23 April 2026. Everything is inside the legal limit, and nothing comes close to it.
9.5 / 10
The tank is as full as the score.
What to do about it
ZeroWater 12-Cup Ready-Pour
£40typical price
Households concerned about PFAS and heavy metals
Waterdrop 10UA Under Sink
£70typical price
High-volume under-sink filtration without RO complexity
BRITA Marella XL + MAXTRA PRO
£25typical price
Basic chlorine and taste improvement on a budget
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What's in a glass of CT4 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.
Nitrate came closest to a limit, at 49% of it. 16 of 17 substances used under a quarter of theirs.
- Nitrate49%
- Colour15%
- Ammonia8%
- Aluminium6%
- Copper5%
- Nickel5%
- Iron5%
- Trihalomethanes4%
- Manganese4%
- Turbidity3%
- Arsenic2%
- Nitrite2%
- Selenium1%
- Antimony<1%
- Lead<1%
- Cadmium<1%
- Chromium<1%
- Coliform Bacteria none found
- E. coli none found
- Conductivity 677 µS/cm
- pH 7.2 pH
All 21 results as a table
| Substance | Result | Legal limit | Share of limit |
|---|---|---|---|
| Manganese | 0.00178 mg/L | 0.05 mg/L | 4% |
| Lead | 0.00009 mg/L | 0.01 mg/L | <1% |
| Coliform Bacteria | 0 count/100ml | Must be zero | None found |
| E. coli | 0 count/100ml | Must be zero | None found |
| Conductivity | 677 µS/cm | No legal limit | – |
| Colour | 3 mg/L Pt/Co | 20 mg/L Pt/Co | 15% |
| Turbidity | 0.13 NTU | 4 NTU | 3% |
| pH | 7.2 pH | No legal limit | – |
| Nitrate | 24.4 mg/L | 50 mg/L | 49% |
| Aluminium | 0.0113 mg/L | 0.2 mg/L | 6% |
| Iron | 0.00928 mg/L | 0.2 mg/L | 5% |
| Nitrite | 0.009 mg/L | 0.5 mg/L | 2% |
| Ammonia | 0.039 mg/L | 0.5 mg/L | 8% |
| Copper | 0.109 mg/L | 2 mg/L | 5% |
| Arsenic | 0.00021 mg/L | 0.01 mg/L | 2% |
| Cadmium | 0.000031 mg/L | 0.005 mg/L | <1% |
| Chromium | 0.00019 mg/L | 0.05 mg/L | <1% |
| Nickel | 0.00105 mg/L | 0.02 mg/L | 5% |
| Antimony | 0.000049 mg/L | 0.005 mg/L | <1% |
| Selenium | 0.00043 mg/L | 0.04 mg/L | 1% |
| Trihalomethanes | 0.00415 mg/L | 0.1 mg/L | 4% |
Your river is the Lampen Stream, rated moderate
The Environment Agency rated the Lampen Stream as moderate for ecological health in its 2025 assessment, meaning the river is noticeably changed by pollution or engineering. It is held back by dissolved oxygen, fish and insects and other small river life. It fails the chemical test, as every river, estuary and stretch of coast in England does, because of long-lasting pollutants such as mercury, PFOS (a forever chemical) and old flame retardants.
None of this is a test of your tap water. Environment Agency record · River health across England
CT4 in short
Tap water in CT4 (Canterbury) is supplied by Southern Water in the Canterbury Central zone and scores 9.5 out of 10, against an England and Wales average of 9.0. None of the 21 tested substances came close to a limit. The latest sample is from 23 April 2026.
- Nitrate is the reading closest to its limit, at 49% of the 50 mg/L maximumIt passed with room to spare, and everything else tested sat further below its limit. See every reading
- 2nd cleanest of 5 areas tested in CanterburyOnly 1 area in Canterbury scored higher. The best is CT2 on 9.5.
- Scores higher than 3 of 4 neighbouring districtsWater here is typical for the immediate area, which usually means the same treatment works and the same supply zone.
Questions about CT4 water
Is CT4 tap water safe to drink?
Based on the latest tests, CT4 (Canterbury) water scores 9.5/10, which is safe. 0 of 21 tested contaminants exceeded recommended levels. Water is supplied by Southern Water.
What contaminants are in CT4 water?
We tested 21 contaminants in CT4 water. None exceeded recommended safe levels.
Who supplies water in CT4?
CT4 (Canterbury) is supplied by Southern Water. You can view their full profile and compliance data on our supplier page.
Should I use a water filter in CT4?
CT4 water scored 9.5/10 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 CT4 water?
No PFAS (forever chemicals) result is attached to the tap-water tests for CT4, 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.
How clean is the river near CT4?
The Environment Agency rated the Lampen Stream as moderate for ecological health in its 2025 assessment, meaning the river is noticeably changed by pollution or engineering. It is held back by dissolved oxygen, fish and insects and other small river life. It fails the chemical test, as every river, estuary and stretch of coast in England does, because of long-lasting pollutants such as mercury, PFOS (a forever chemical) and old flame retardants. This is a rating of the river, not of tap water in CT4, which is treated before it reaches homes.
Keep reading
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- Best Water Filter Jug UKBRITA vs ZeroWater vs the rest, tested against real data
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River and groundwater readings near CT4
Environment Agency samples from rivers, groundwater and reservoirs nearby. Not your tap water. For scale they are shown against drinking water limits; rivers are judged against much stricter environmental standards, and on those every river in England fails for chemicals.
Get alerts for your area
We'll email you when water quality data changes for CT4.