Tap water in TN40, RotherSafe to drink.Slightly hard.
Supplied by Southern Water. 368 samples, 14 substances, latest on 22 April 2026. Everything is inside the legal limit, and nothing comes close to it.
9.7 / 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 TN40 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.
Colour came closest to a limit, at 15% of it. 10 of 10 substances used under a quarter of theirs.
- Colour15%
- Lead6%
- Nitrate6%
- Aluminium6%
- Iron5%
- Nickel5%
- Turbidity4%
- Manganese4%
- Ammonia2%
- Copper<1%
- pH 7.9 pH
- Conductivity 255 µS/cm
- Coliform Bacteria none found
- E. coli none found
All 14 results as a table
| Substance | Result | Legal limit | Share of limit |
|---|---|---|---|
| pH | 7.9 pH | No legal limit | – |
| Lead | 0.00059 mg/L | 0.01 mg/L | 6% |
| Conductivity | 255 µS/cm | No legal limit | – |
| Aluminium | 0.0113 mg/L | 0.2 mg/L | 6% |
| Iron | 0.00928 mg/L | 0.2 mg/L | 5% |
| Manganese | 0.00178 mg/L | 0.05 mg/L | 4% |
| Coliform Bacteria | 0 count/100ml | Must be zero | None found |
| E. coli | 0 count/100ml | Must be zero | None found |
| Colour | 3 mg/L Pt/Co | 20 mg/L Pt/Co | 15% |
| Turbidity | 0.153 NTU | 4 NTU | 4% |
| Nitrate | 2.83 mg/L | 50 mg/L | 6% |
| Ammonia | 0.008 mg/L | 0.5 mg/L | 2% |
| Copper | 0.0023 mg/L | 2 mg/L | <1% |
| Nickel | 0.00091 mg/L | 0.02 mg/L | 5% |
150mg of limescale minerals in every litre, typical for the TN area. TN40 has no reading of its own.
Middling hardness. Some scale, slowly
Below the point where a softener pays for itself. Descaling the kettle now and then is all most homes need.
Your river is the Combe Haven between Powdermill Str conf and Coast, rated poor
The Environment Agency rated the Combe Haven between Powdermill Str conf and Coast as poor for ecological health in its 2025 assessment, meaning the river is badly affected, with much of the expected wildlife missing. It is held back by fish, water plants and algae and dissolved oxygen. 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
TN40 in short
Tap water in TN40 (Rother) is supplied by Southern Water in the Rother Central zone and scores 9.7 out of 10, against an England and Wales average of 9.0. None of the 14 tested substances came close to a limit. The latest sample is from 22 April 2026.
- The cleanest tap water of the 8 areas tested in RotherTN40 scores 9.7 out of 10, ahead of TN19 in second place on 9.6.
- Scores higher than all 7 neighbouring districtsThe nearest rival is TN32 on 9.6, against 9.7 here. Compare with TN32
- 0.7 points above the national average of 9Cleaner than the typical tested district in the UK. Compare every area
Questions about TN40 water
Is TN40 tap water safe to drink?
Based on the latest tests, TN40 (Rother) water scores 9.7/10, which is safe. 0 of 14 tested contaminants exceeded recommended levels. Water is supplied by Southern Water.
What contaminants are in TN40 water?
We tested 14 contaminants in TN40 water. None exceeded recommended safe levels.
Who supplies water in TN40?
TN40 (Rother) is supplied by Southern Water. You can view their full profile and compliance data on our supplier page.
Is TN40 water hard or soft?
No hardness reading has been published for TN40 itself. Across the TN postcode area the typical value is 150 mg/L CaCO3, which is classified as moderately hard. This is a moderate hardness level.
Should I use a water filter in TN40?
TN40 water scored 9.7/10 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 TN40 water?
No PFAS (forever chemicals) result is attached to the tap-water tests for TN40, 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 TN40?
The Environment Agency rated the Combe Haven between Powdermill Str conf and Coast as poor for ecological health in its 2025 assessment, meaning the river is badly affected, with much of the expected wildlife missing. It is held back by fish, water plants and algae and dissolved oxygen. 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 TN40, which is treated before it reaches homes.
Keep reading
- 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
- How to Test Your Tap WaterFrom DIY strips to professional lab analysis
- Best Water Filter Jug UKBRITA vs ZeroWater vs the rest, tested against real data
How to test your waterBest water filtersFilter shower headsWater testing kitsUK water rankingsWater hardness checkerWater hardness map
River and groundwater readings near TN40
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 TN40.