Tap water in RH16, Mid SussexIron is over the limit.Slightly hard.
Supplied by Southern Water. 9 substances, latest on 3 July 2026. Iron came in above the legal limit. Everything else passed.
7.0 / 10
The tank is as full as the score. The specks are the minerals that make water hard.
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What's in a glass of RH16 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.
Iron is over its legal limit, at 785% of it.
- Iron785%
- Ammonia50%
- Nitrite5%
- Nitrate2%
- pH 7.37 pH
- Temperature 17.9 °C
- Conductivity 224 µS/cm
- Phosphate 0.025 mg/L
- Dissolved Oxygen 7.36 mg/L
All 9 results as a table
| Substance | Result | Legal limit | Share of limit |
|---|---|---|---|
| Iron | 1.57 mg/L | 0.2 mg/L | 785% |
| pH | 7.37 pH | No legal limit | – |
| Temperature | 17.9 °C | No legal limit | – |
| Conductivity | 224 µS/cm | No legal limit | – |
| Ammonia | 0.25 mg/L | 0.5 mg/L | 50% |
| Nitrate | 0.82 mg/L | 50 mg/L | 2% |
| Nitrite | 0.025 mg/L | 0.5 mg/L | 5% |
| Phosphate | 0.025 mg/L | No legal limit | – |
| Dissolved Oxygen | 7.36 mg/L | No legal limit | – |
148mg of limescale minerals in every litre, typical for the RH area. RH16 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 Scrase Bridge Stream at Haywards Heath, rated moderate
The Environment Agency rated the Scrase Bridge Stream at Haywards Heath as moderate for ecological health in its 2025 assessment, meaning the river 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
54
forever-chemical detections in nearby rivers and groundwater
At 1 site. The highest was PFBS at 0.057 µg/L, at RSN0537 Adur East Churchill Way Burgesshill, 5.4 km away, in July 2026. These are river and borehole samples, not tests of your tap water.
Every PFAS sample around Brighton · Which filters remove PFAS · PFAS explained
RH16 in short
Tap water in RH16 (Mid Sussex) is supplied by Southern Water in the Mid Sussex Central zone and scores 7.0 out of 10, against an England and Wales average of 9.0. 1 of 9 tested substances was close to or over a limit. The latest sample is from 3 July 2026.
- Iron was measured at 1.57 mg/L, 7.9 times the UK limitIt is the only one of 9 tested substances to go over its limit. See the full results
- The lowest score of the 5 areas tested in Mid SussexRH16 scores 7 out of 10. The best in Mid Sussex, BN45, scores 9.4.
- Every one of the 4 neighbouring districts scores higherBN45 next door scores 9.4, against 7 here. Supply zones, not distance, explain the gap. See BN45
Questions about RH16 water
Is RH16 tap water safe to drink?
Based on the latest tests, RH16 (Mid Sussex) water scores 7/10, which is safe. 1 of 9 tested contaminants exceeded recommended levels. Water is supplied by Southern Water.
What contaminants are in RH16 water?
We tested 9 contaminants in RH16 water. 1 were flagged, including Iron. 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 RH16?
RH16 (Mid Sussex) is supplied by Southern Water. You can view their full profile and compliance data on our supplier page.
Is RH16 water hard or soft?
No hardness reading has been published for RH16 itself. Across the RH postcode area the typical value is 148 mg/L CaCO3, which is classified as moderately hard. This is a moderate hardness level.
Should I use a water filter in RH16?
With 1 contaminant above recommended levels in RH16, a water filter could help. A reverse osmosis or activated carbon filter is recommended for PFAS removal. See our filter recommendations for your area.
Are there PFAS forever chemicals in RH16 water?
The tap-water tests we hold for RH16 do not include a PFAS result. Environment Agency monitoring found PFAS in 54 river and groundwater samples from 1 sites within 10 km of RH16, the highest being PFBS at 0.057 µg/L about 5.4 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 RH16?
The Environment Agency rated the Scrase Bridge Stream at Haywards Heath as moderate for ecological health in its 2025 assessment, meaning the river 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 river, not of tap water in RH16, 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
- Best Water Filters UKEvery filter type compared on what it actually removes
- Is UK Tap Water Safe?Everything you need to know about tap water safety in the UK
PFAS explainedHow to test your waterBest water filtersFilter shower headsWater testing kitsUK water rankingsWater hardness checkerWater hardness map
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