Tap water in KT10, ElmbridgeSafe to drink.Moderately soft.
Supplied by Thames Water. 71 samples, 23 substances, latest on 31 December 2025. Everything is inside the legal limit, and nothing comes close to it.
9.1 / 10
The tank is as full as the score. The specks are the minerals that make water hard.
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 KT10 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.
Nitrite came closest to a limit, at 68% of it. 17 of 19 substances used under a quarter of theirs.
- Nitrite68%
- Nitrate34%
- Nickel12%
- Bromate10%
- Lead9%
- Colour9%
- Cadmium8%
- Iron8%
- Mercury7%
- Arsenic7%
- Fluoride6%
- Antimony6%
- Copper6%
- Chromium5%
- Trihalomethanes5%
- Aluminium4%
- Boron2%
- Manganese2%
- Selenium1%
- Coliform Bacteria none found
- E. coli none found
- Conductivity 245 µS/cm
All 23 results as a table
| Substance | Result | Legal limit | Share of limit |
|---|---|---|---|
| Coliform Bacteria | 0 count/100ml | Must be zero | None found |
| E. coli | 0 count/100ml | Must be zero | None found |
| Colour | 1.8 mg/L Pt/Co | 20 mg/L Pt/Co | 9% |
| Conductivity | 245 µS/cm | No legal limit | – |
| Fluoride | 0.09 mg/L | 1.5 mg/L | 6% |
| Nitrate | 17 mg/L | 50 mg/L | 34% |
| Nitrite | 0.34 mg/L | 0.5 mg/L | 68% |
| Hardness (as CaCO3) | 75 mg/L | No legal limit | – |
| Aluminium | 0.0082 mg/L | 0.2 mg/L | 4% |
| Antimony | 0.0003 mg/L | 0.005 mg/L | 6% |
| Arsenic | 0.0007 mg/L | 0.01 mg/L | 7% |
| Boron | 0.02 mg/L | 1 mg/L | 2% |
| Cadmium | 0.0004 mg/L | 0.005 mg/L | 8% |
| Chromium | 0.0025 mg/L | 0.05 mg/L | 5% |
| Copper | 0.11 mg/L | 2 mg/L | 6% |
| Iron | 0.016 mg/L | 0.2 mg/L | 8% |
| Lead | 0.0009 mg/L | 0.01 mg/L | 9% |
| Manganese | 0.0009 mg/L | 0.05 mg/L | 2% |
| Mercury | 0.00007 mg/L | 0.001 mg/L | 7% |
| Nickel | 0.0024 mg/L | 0.02 mg/L | 12% |
| Selenium | 0.0004 mg/L | 0.04 mg/L | 1% |
| Trihalomethanes | 0.005 mg/L | 0.1 mg/L | 5% |
| Bromate | 0.001 mg/L | 0.01 mg/L | 10% |
75mg of limescale minerals in every litre
Soft water. Kind to kettles, boilers and skin
You will not need a softener here, and you will use less soap and detergent than most of England.
Your river is the Rythe, rated moderate
The Environment Agency rated the Rythe as moderate for ecological health in its 2025 assessment, meaning the river is noticeably changed by pollution or engineering. It is held back by fish, phosphate 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. Its ecological rating has improved since the previous assessment.
None of this is a test of your tap water. Environment Agency record · River health across England
12
forever-chemical detections in nearby rivers and groundwater
At 1 site. The highest was PFPeA at 0.038 µg/L, at Twickenham, Meadowbank House Bh, 10M :TQ17/126, 9.7 km away, in June 2023. These are river and borehole samples, not tests of your tap water.
Every PFAS sample around London · Which filters remove PFAS · PFAS explained
KT10 in short
Tap water in KT10 (Elmbridge) is supplied by Thames Water in the Elmbridge Central zone and scores 9.1 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 31 December 2025.
- Nitrite is the reading closest to its limit, at 68% of the 0.5 mg/L maximumIt passed with room to spare, and everything else tested sat further below its limit. See every reading
- 2nd cleanest of 6 areas tested in ElmbridgeOnly 1 area in Elmbridge scored higher. The best is KT11 on 9.3.
- PFAS found at 1 monitoring site within 10 kmThose are river and groundwater samples, not tap water. The highest was PFPeA about 9.7 km away. What was measured
Questions about KT10 water
Is KT10 tap water safe to drink?
Based on the latest tests, KT10 (Elmbridge) water scores 9.1/10, which is safe. 0 of 23 tested contaminants exceeded recommended levels. Water is supplied by Thames Water.
What contaminants are in KT10 water?
We tested 23 contaminants in KT10 water. None exceeded recommended safe levels. PFAS (forever chemicals) were also measured in rivers and groundwater within 10 km, though not in the tap-water tests themselves.
Who supplies water in KT10?
KT10 (Elmbridge) is supplied by Thames Water. You can view their full profile and compliance data on our supplier page.
Is KT10 water hard or soft?
Water in KT10 (Elmbridge) has a hardness of 75 mg/L CaCO3, which is classified as moderately soft. This is a moderate hardness level.
Should I use a water filter in KT10?
KT10 water scored 9.1/10 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 KT10 water?
The tap-water tests we hold for KT10 do not include a PFAS result. Environment Agency monitoring found PFAS in 12 river and groundwater samples from 1 sites within 10 km of KT10, the highest being PFPeA at 0.038 µg/L about 9.7 km away. These are environmental samples, not tests of tap water. The UK currently has no legal limit for PFAS in drinking water; the Drinking Water Inspectorate uses a 0.1 µg/L guideline for individual compounds. Reverse osmosis filters can reduce PFAS levels.
How clean is the river near KT10?
The Environment Agency rated the Rythe as moderate for ecological health in its 2025 assessment, meaning the river is noticeably changed by pollution or engineering. It is held back by fish, phosphate 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. Its ecological rating has improved since the previous assessment. This is a rating of the river, not of tap water in KT10, which is treated before it reaches homes.
Keep reading
- Best Filter for PFAS RemovalThe filters with independent certification to remove forever chemicals
- PFAS Forever ChemicalsWhat PFAS are and how to reduce your exposure at home
- Is UK Tap Water Safe?Everything you need to know about tap water safety in the UK
- Best Water Filters UKEvery filter type compared on what it actually removes
PFAS explainedHow to test your waterBest water filtersFilter shower headsWater testing kitsUK water rankingsWater hardness checkerWater hardness map
River and groundwater readings near KT10
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.
| Substance | Reading | Drinking water limit |
|---|---|---|
| pH | 0.21 pH | None |
| Dissolved Oxygen | 8.74 mg/L | None |
| Temperature | 12.9 °C | None |
| Conductivity | 717 µS/cm | None |
| Nitrate | 13 mg/L | 50 mg/L |
| Nitrite | 0.026 mg/L | 0.5 mg/L |
| Phosphate | 0.21 mg/L | None |
| Ammonia | 0.17 mg/L | 0.5 mg/L |
| Zinc | 0.0017 mg/L | None |
| Copper | 0.0025 mg/L | 2 mg/L |
| Manganese | 0.019 mg/L | 0.05 mg/L |
| Iron | 0.072 mg/L | 0.2 mg/L |
| PFAS (total) | 0.0073 µg/L | None |
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