Tap water in RH10, CrawleyTurbidity is over the limit.Very hard.
Supplied by South East Water. 10 substances, latest on 28 October 2026. Turbidity came in above the legal limit. Everything else passed.
8.0 / 10
The tank is as full as the score. The specks are the minerals that make water hard.
What to do about it
Osmio PRO-III Ultimate Whole House
£499typical price
Removes turbidity, the result that stood out in RH10.
Stop the limescale
At 204 mg/L a softener is the only thing that stops limescale. Filters do not soften water.
BWT E1 Single Lever
£250typical price
Removes turbidity, the result that stood out in RH10.
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What's in a glass of RH10 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.
Turbidity is over its legal limit, at 875% of it.
- Turbidity875%
- Nitrite19%
- Nitrate11%
- Ammonia7%
- Cadmium1%
- pH 7.27 pH
- Temperature 10.9 °C
- Conductivity 457 µS/cm
- Phosphate 0.06 mg/L
- Dissolved Oxygen 8.85 mg/L
All 10 results as a table
| Substance | Result | Legal limit | Share of limit |
|---|---|---|---|
| Turbidity | 35 NTU | 4 NTU | 875% |
| pH | 7.27 pH | No legal limit | – |
| Temperature | 10.9 °C | No legal limit | – |
| Conductivity | 457 µS/cm | No legal limit | – |
| Ammonia | 0.037 mg/L | 0.5 mg/L | 7% |
| Nitrate | 5.3 mg/L | 50 mg/L | 11% |
| Nitrite | 0.096 mg/L | 0.5 mg/L | 19% |
| Phosphate | 0.06 mg/L | No legal limit | – |
| Dissolved Oxygen | 8.85 mg/L | No legal limit | – |
| Cadmium | 0.00005 mg/L | 0.005 mg/L | 1% |
204mg of limescale minerals in every litre
This is the water that furs up kettles
Very hard on the UK scale. It is fine to drink. It is hard on boilers, showers, skin and anything that heats water, and a jug or tap filter will not change that.
Softener quotes for RH10
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Your river is the Tilgate Brook and Gatwick Stream at Crawley, rated moderate
The Environment Agency rated the Tilgate Brook and Gatwick Stream at Crawley as moderate for ecological health in its 2025 assessment, meaning the river is noticeably changed by pollution or engineering. It is held back by insects and other small river life, fish and phosphate. 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
RH10 in short
Tap water in RH10 (Crawley) is supplied by South East Water in the Crawley Central zone and scores 8.0 out of 10, against an England and Wales average of 9.0. 1 of 10 tested substances was close to or over a limit. The latest sample is from 28 October 2026.
- Turbidity was measured at 35 NTU, 8.8 times the UK limitIt is the only one of 10 tested substances to go over its limit. See the full results
- Hard water at 204 mg/LHard starts at 180 mg/L, the point where a softener begins to pay for itself. Limescale will build up in RH10. How hardness is measured
- 1 point below the national average of 9Below the typical tested district in the UK, which is worth knowing before you choose a filter. Compare every area
Next door
Questions about RH10 water
Is RH10 tap water safe to drink?
Based on the latest tests, RH10 (Crawley) water scores 8/10, which is safe. 1 of 10 tested contaminants exceeded recommended levels. Water is supplied by South East Water.
What contaminants are in RH10 water?
We tested 10 contaminants in RH10 water. 1 were flagged, including Turbidity.
Who supplies water in RH10?
RH10 (Crawley) is supplied by South East Water. You can view their full profile and compliance data on our supplier page.
Is RH10 water hard or soft?
Water in RH10 (Crawley) has a hardness of 204 mg/L CaCO3, which is classified as hard. Hard water can cause limescale buildup. A water softener or filter jug may help.
Should I use a water filter in RH10?
With 1 contaminant above recommended levels in RH10, a water filter could help. A filter jug or under-sink filter can reduce most common contaminants. See our filter recommendations for your area.
Are there PFAS forever chemicals in RH10 water?
No PFAS (forever chemicals) result is attached to the tap-water tests for RH10, 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 RH10?
The Environment Agency rated the Tilgate Brook and Gatwick Stream at Crawley as moderate for ecological health in its 2025 assessment, meaning the river is noticeably changed by pollution or engineering. It is held back by insects and other small river life, fish and phosphate. 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 RH10, which is treated before it reaches homes.
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