Tap water in L33, KnowsleySafe to drink.Moderately soft.
Supplied by United Utilities. 1,404 samples, 16 substances, latest on 29 December 2024. Everything is inside the legal limit, and nothing comes close to it.
9.4 / 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 L33 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.
Trihalomethanes came closest to a limit, at 24% of it. 16 of 16 substances used under a quarter of theirs.
- Trihalomethanes24%
- Nitrate19%
- Ammonia6%
- Antimony6%
- Bromate6%
- Lead6%
- Turbidity4%
- Nickel4%
- Iron3%
- Aluminium3%
- Selenium2%
- Cadmium2%
- Chromium2%
- Nitrite2%
- Manganese<1%
- Copper<1%
All 16 results as a table
| Substance | Result | Legal limit | Share of limit |
|---|---|---|---|
| Turbidity | 0.16 NTU | 4 NTU | 4% |
| Ammonia | 0.0321 mg/L | 0.5 mg/L | 6% |
| Cadmium | 0.00009 mg/L | 0.005 mg/L | 2% |
| Chromium | 0.00083 mg/L | 0.05 mg/L | 2% |
| Antimony | 0.00031 mg/L | 0.005 mg/L | 6% |
| Selenium | 0.00085 mg/L | 0.04 mg/L | 2% |
| Copper | 0.0000104 mg/L | 2 mg/L | <1% |
| Nickel | 0.00077 mg/L | 0.02 mg/L | 4% |
| Lead | 0.00055 mg/L | 0.01 mg/L | 6% |
| Nitrate | 9.26 mg/L | 50 mg/L | 19% |
| Nitrite | 0.0075 mg/L | 0.5 mg/L | 2% |
| Aluminium | 0.00655 mg/L | 0.2 mg/L | 3% |
| Iron | 0.007 mg/L | 0.2 mg/L | 3% |
| Manganese | 0.00045 mg/L | 0.05 mg/L | <1% |
| Bromate | 0.00057 mg/L | 0.01 mg/L | 6% |
| Trihalomethanes | 0.0237 mg/L | 0.1 mg/L | 24% |
93mg 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 Simonswood Brook, rated moderate
The Environment Agency rated the Simonswood Brook 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, insects and other small river life 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
78
forever-chemical detections in nearby rivers and groundwater
At 5 sites. The highest was PFBA at 0.96 µg/L, at Kodak Ltd. Acorn Road. Wrb No SJ49/64, 2.1 km away, in June 2024. These are river and borehole samples, not tests of your tap water.
Every PFAS sample around Liverpool · Which filters remove PFAS · PFAS explained
L33 in short
Tap water in L33 (Knowsley) is supplied by United Utilities in the Knowsley Central zone and scores 9.4 out of 10, against an England and Wales average of 9.0. None of the 16 tested substances came close to a limit. The latest sample is from 29 December 2024.
- The cleanest tap water of the 7 areas tested in KnowsleyL33 scores 9.4 out of 10, ahead of L26 in second place on 9.3.
- Scores higher than all 7 neighbouring districtsThe nearest rival is L36 on 9.3, against 9.4 here. Compare with L36
- PFAS found at 5 monitoring sites within 10 kmThose are river and groundwater samples, not tap water. The highest was PFBA about 2.1 km away. What was measured
Questions about L33 water
Is L33 tap water safe to drink?
Based on the latest tests, L33 (Knowsley) water scores 9.4/10, which is safe. 0 of 16 tested contaminants exceeded recommended levels. Water is supplied by United Utilities.
What contaminants are in L33 water?
We tested 16 contaminants in L33 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 L33?
L33 (Knowsley) is supplied by United Utilities. You can view their full profile and compliance data on our supplier page.
Is L33 water hard or soft?
Water in L33 (Knowsley) has a hardness of 93 mg/L CaCO3, which is classified as moderately soft. This is a moderate hardness level.
Should I use a water filter in L33?
L33 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 L33 water?
The tap-water tests we hold for L33 do not include a PFAS result. Environment Agency monitoring found PFAS in 78 river and groundwater samples from 5 sites within 10 km of L33, the highest being PFBA at 0.96 µg/L about 2.1 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 L33?
The Environment Agency rated the Simonswood Brook 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, insects and other small river life 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 L33, 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 L33
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 | 7.53 pH | None |
| Temperature | 14.2 °C | None |
| Conductivity | 521 µS/cm | None |
| Ammonia | 0.17 mg/L | 0.5 mg/L |
| Nitrate | 2.1 mg/L | 50 mg/L |
| Nitrite | 0.085 mg/L | 0.5 mg/L |
| Phosphate | 0.24 mg/L | None |
| Dissolved Oxygen | 4.27 mg/L | None |
| Zinc | 0.011 mg/L | None |
| Nickel | 0.0083 mg/L | 0.02 mg/L |
| Aluminium | 0.013 mg/L | 0.2 mg/L |
| Copper | 0.0023 mg/L | 2 mg/L |
Get alerts for your area
We'll email you when water quality data changes for L33.