Tap water in CT20, Folkestone and HytheSafe to drink.
Supplied by Southern Water. 844 samples, 24 substances, latest on 12 December 2025. Everything is inside the legal limit, and nothing comes close to it.
9.4 / 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 CT20 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 52% of it. 20 of 21 substances used under a quarter of theirs.
- Nitrate52%
- Bromate15%
- Ammonia12%
- Colour10%
- Lead7%
- Fluoride6%
- Trihalomethanes5%
- Boron5%
- Iron4%
- Copper4%
- Nickel3%
- Turbidity3%
- Mercury2%
- Nitrite2%
- Selenium1%
- Arsenic1%
- Cadmium1%
- Aluminium<1%
- Chromium<1%
- Manganese<1%
- Antimony<1%
- Coliform Bacteria none found
- Conductivity 487 µS/cm
- E. coli none found
All 24 results as a table
| Substance | Result | Legal limit | Share of limit |
|---|---|---|---|
| Coliform Bacteria | 0 count/100ml | Must be zero | None found |
| Conductivity | 487 µS/cm | No legal limit | – |
| E. coli | 0 count/100ml | Must be zero | None found |
| Copper | 0.076 mg/L | 2 mg/L | 4% |
| Arsenic | 0.000135 mg/L | 0.01 mg/L | 1% |
| Fluoride | 0.085 mg/L | 1.5 mg/L | 6% |
| Manganese | 0.000363 mg/L | 0.05 mg/L | <1% |
| Colour | 2 mg/L Pt/Co | 20 mg/L Pt/Co | 10% |
| Mercury | 0.000023 mg/L | 0.001 mg/L | 2% |
| Selenium | 0.00059 mg/L | 0.04 mg/L | 1% |
| Ammonia | 0.06 mg/L | 0.5 mg/L | 12% |
| Chromium | 0.000383 mg/L | 0.05 mg/L | <1% |
| Antimony | 0.000027 mg/L | 0.005 mg/L | <1% |
| Nitrite | 0.01 mg/L | 0.5 mg/L | 2% |
| Aluminium | 0.00199 mg/L | 0.2 mg/L | <1% |
| Iron | 0.00897 mg/L | 0.2 mg/L | 4% |
| Turbidity | 0.1 NTU | 4 NTU | 3% |
| Nickel | 0.000611 mg/L | 0.02 mg/L | 3% |
| Trihalomethanes | 0.0047 mg/L | 0.1 mg/L | 5% |
| Cadmium | 0.000054 mg/L | 0.005 mg/L | 1% |
| Nitrate | 26.2 mg/L | 50 mg/L | 52% |
| Boron | 0.046 mg/L | 1 mg/L | 5% |
| Lead | 0.000673 mg/L | 0.01 mg/L | 7% |
| Bromate | 0.00147 mg/L | 0.01 mg/L | 15% |
Your coastal water is the Kent South, rated moderate
The Environment Agency rated the Kent South as moderate for ecological health in its 2025 assessment, meaning the coastal water is noticeably changed by pollution or engineering. 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
CT20 in short
Tap water in CT20 (Folkestone and Hythe) is supplied by Southern Water in the Folkestone and Hythe Central zone and scores 9.4 out of 10, against an England and Wales average of 9.0. None of the 24 tested substances came close to a limit. The latest sample is from 12 December 2025.
- Nitrate is the reading closest to its limit, at 52% of the 50 mg/L maximumIt passed with room to spare, and everything else tested sat further below its limit. See every reading
- 3rd cleanest of 6 areas tested in Folkestone and HytheSquarely mid-table for Folkestone and Hythe, between CT18 on 9.5 and TN29 on 9.1.
- Scores higher than 2 of 5 neighbouring districtsWater here is typical for the immediate area, which usually means the same treatment works and the same supply zone.
Questions about CT20 water
Is CT20 tap water safe to drink?
Based on the latest tests, CT20 (Folkestone and Hythe) water scores 9.4/10, which is safe. 0 of 24 tested contaminants exceeded recommended levels. Water is supplied by Southern Water.
What contaminants are in CT20 water?
We tested 24 contaminants in CT20 water. None exceeded recommended safe levels.
Who supplies water in CT20?
CT20 (Folkestone and Hythe) 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 CT20?
CT20 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 CT20 water?
No PFAS (forever chemicals) result is attached to the tap-water tests for CT20, 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 coastal water near CT20?
The Environment Agency rated the Kent South as moderate for ecological health in its 2025 assessment, meaning the coastal water is noticeably changed by pollution or engineering. 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 coastal water, not of tap water in CT20, which is treated before it reaches homes.
Keep reading
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River and groundwater readings near CT20
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 CT20.