Hemel/Kings Langley: your water explained
Published results for this named supply area. Your address may be served by a different area.
Confirm your address · Check a postcode
Check your full postcode before assuming this area report describes the water serving your address.
Your water at a glance
Very hard water. Expect limescale.
For your home, the main practical issue is mineral scale in kettles, showers and appliances. Check your dishwasher setting and follow appliance care instructions.
305 mg/l as CaCO₃
Soft ≤100 · Slightly hard ≤150 · Moderately hard ≤200 · Hard ≤300 · Very hard >300 mg/l. DWI hardness bands; not safety grades.
Published quality checks
41 parameters: no exceedances reported
These labels describe 2025. 3 other parameters have no complete compliance judgement here. They are not a guarantee about an individual tap today.
Understand the reported results ↓Make this useful for your home
Hardness reporting period: 2025 · Quality reporting period: 2025
Appliance settings · Convert hardness units
3.05 mmol/l
A conversion of the published hardness, not another test. Follow your appliance’s model-specific instructions.
Drinking-water results
What do the important results mean?
Read the status, sample range and source requirement together. A low average can hide an individual exceedance. Green labels mean the supplier reported no exceedances for that parameter and period; amber calls for source context.
E. coli
✓ No exceedances reported
Published mean
0 No./100ml
Source reference: 0 No./100ml
A microbiological indicator. The reported sample results and any failures matter more than an average bacterial count.
84 samples · Range: 0 to 0 No./100ml
The source reports 0 failures across 84 samples. This describes the published period.
Lead
✓ No exceedances reported
Published mean
1.05 μgPb/l
Source reference: 10 μgPb/l
Plumbing can affect lead at an individual tap. An area average cannot rule out a problem with pipes at your property.
8 samples · Range: <0.67 to 3.93 μgPb/l
The source reports 0 failures across 8 samples. This describes the published period.
Nitrate
✓ No exceedances reported
Published mean
23.7 mgNO3/l
Source reference: 50 mgNO3/l
A dissolved compound monitored against drinking-water requirements. Its mean, highest reported result and sample count answer different questions.
8 samples · Range: 17.8 to 26.4 mgNO3/l
The source reports 0 failures across 8 samples. This describes the published period.
Fluoride
✓ No exceedances reported
Published mean
0.092 mgF/l
Source reference: 1.5 mgF/l
Can occur naturally or be added through a fluoridation scheme. The concentration alone does not tell you whether it was added; a lower number is not automatically better.
8 samples · Range: 0.086 to 0.101 mgF/l
The source reports 0 failures across 8 samples. This describes the published period.
For your household
What should you do next?
Check appliance settings
Match the hardness unit to your dishwasher manual. Settings depend on the model.
Dishwasher guideManage limescale
Follow the manufacturer’s descaling advice. Check what a filter actually removes before buying.
Filters and limescaleA new change at your tap?
For a new taste, smell, colour or supply problem, check current supplier advice. Annual data is not a live incident feed.
Official supplier help ↗Taste, appearance and mineral content
Chlorine, pH and minerals answer different questions. Calcium and magnesium help describe hardness; chloride is different from treatment chlorine. None is a stand-alone water-quality score.
Chlorine residual
Disinfectant remaining after treatment. It can influence taste and smell; a lower concentration is not automatically better.
See the measurement and context ↓pH
Describes acidity and alkalinity on a scale, rather than an amount of a substance. Where the source gives a range, both its lower and upper bounds matter.
See the measurement and context ↓Calcium
A naturally occurring mineral that contributes to hardness. Calcium alone is not the same measurement as total hardness.
See the measurement and context ↓Has the hardness changed?
History for this reported source area. Only comparable annual statistics appear in the chart; rolling summaries are kept separate. These are not daily tests at your address.
A comparable historical series is not available yet. We will add earlier reports when we can verify their periods and source areas.
Explore all measurements · 46 parameters · 2025
Every result retains its original units, range, sample count and source notes. Comparisons use the reference printed in this report; qualitative references and missing limits are not converted into invented pass/fail judgements. Unlisted substances are not necessarily absent from the water.
Parameters without their own explanation: A substance monitored in this supplier report. The source reference, units, sample range and any reported failures provide its context; the number alone is not a water-quality rating.
A failure count (under “Original wording and source notes”) supports a pass/fail label only where the report gives an applicable limit for that parameter.
Hardness and minerals 7 parameters
Alkalinity
No numerical limit supplied
Published mean
325 mgHCO3/l
Source reference: No numerical limit supplied
How strongly water resists a change in acidity. This helps describe its chemistry; it is different from pH and total hardness.
1 sample · Range: 325 to 325 mgHCO3/l
This report gives no numerical limit for this parameter. A higher or lower number is not automatically better.
Original wording and source notes
Source reference: No PCV. Source parameter: Alkalinity. Original mean: 325 mgHCO3/l.
Source failure-count field: 0.
Calcium
No numerical limit supplied
Published mean
122 mgCa/l
Source reference: No numerical limit supplied
A naturally occurring mineral that contributes to hardness. Calcium alone is not the same measurement as total hardness.
1 sample · Range: 122 to 122 mgCa/l
This report gives no numerical limit for this parameter. A higher or lower number is not automatically better.
Original wording and source notes
Source reference: No PCV. Source parameter: Calcium. Original mean: 122 mgCa/l.
Source failure-count field: 0.
Fluoride
✓ No exceedances reported
Published mean
0.092 mgF/l
Source reference: 1.5 mgF/l
Can occur naturally or be added through a fluoridation scheme. The concentration alone does not tell you whether it was added; a lower number is not automatically better.
8 samples · Range: 0.086 to 0.101 mgF/l
The source reports 0 failures across 8 samples. This describes the published period.
Original wording and source notes
Source reference: 1.5. Source parameter: Fluoride. Original mean: 0.092 mgF/l.
Source failure-count field: 0.
Total hardness
No numerical limit supplied
Published mean
305 mgCaCO3/l
Source reference: No numerical limit supplied
Dissolved calcium and magnesium affect limescale and appliance settings. This is a mineral description, not a safety score.
1 sample · Range: 305 to 305 mgCaCO3/l
This report gives no numerical limit for this parameter. A higher or lower number is not automatically better.
Original wording and source notes
Source reference: No PCV. Source parameter: Hardness (Total). Original mean: 305 mgCaCO3/l.
Source failure-count field: 0.
Sodium
✓ No exceedances reported
Published mean
10.5 mgNa/l
Source reference: 200 mgNa/l
A dissolved salt component. Compare the water measurement with its source reference; it is not a measure of your total dietary salt intake.
8 samples · Range: 8.1 to 15.3 mgNa/l
The source reports 0 failures across 8 samples. This describes the published period.
Original wording and source notes
Source reference: 200. Source parameter: Sodium. Original mean: 10.5 mgNa/l.
Source failure-count field: 0.
Chloride
✓ No exceedances reported
Published mean
21 mgCl/l
Source reference: 250 mgCl/l
A dissolved salt component that can influence taste at higher concentrations. It is different from chlorine used in treatment.
8 samples · Range: 16 to 27 mgCl/l
The source reports 0 failures across 8 samples. This describes the published period.
Original wording and source notes
Source reference: 250. Source parameter: Chloride. Original mean: 21 mgCl/l.
Source failure-count field: 0.
Sulphate
✓ No exceedances reported
Published mean
<11 mgSO4/l
Source reference: 250 mgSO4/l
A dissolved mineral component monitored in water-quality reports. Read its concentration alongside the source reference.
8 samples · Range: <11 to 18 mgSO4/l
The source reports 0 failures across 8 samples. This describes the published period.
“<” is part of the source result. It is not an exact concentration or a measured zero.
Original wording and source notes
Source reference: 250. Source parameter: Sulphate. Original mean: <11 mgSO4/l.
Source failure-count field: 0.
Taste, appearance and treatment 6 parameters
Chlorine residual
No numerical limit supplied
Published mean
0.26 mgCl2/l
Source reference: No numerical limit supplied
Disinfectant remaining after treatment. It can influence taste and smell; a lower concentration is not automatically better.
84 samples · Range: <0.05 to 0.95 mgCl2/l
This report gives no numerical limit for this parameter. A higher or lower number is not automatically better.
Original wording and source notes
Source reference: No PCV. Source parameter: Chlorine (Residual). Original mean: 0.26 mgCl2/l.
Source failure-count field: 0.
Colour
✓ No exceedances reported
Published mean
<2.0 mg/l Pt/Co
Source reference: 20 mg/l Pt/Co
A measure of water colour under test conditions. A new change at your tap should be checked with your supplier.
36 samples · Range: <1.9 to <2.0 mg/l Pt/Co
The source reports 0 failures across 36 samples. This describes the published period.
“<” is part of the source result. It is not an exact concentration or a measured zero.
Original wording and source notes
Source reference: 20. Source parameter: Colour. Original mean: <2.0 mg/l Pt/Co.
Source failure-count field: 0.
pH
✓ No exceedances reported
Published mean
7 pH value
Source reference: 6.5-9.5 pH value
Describes acidity and alkalinity on a scale, rather than an amount of a substance. Where the source gives a range, both its lower and upper bounds matter.
36 samples · Range: 6.8 to 7.7 pH value
The source reports 0 failures across 36 samples. This describes the published period.
Original wording and source notes
Source reference: 6.5-9.5. Source parameter: Hydrogen Ion (pH). Original mean: 7 pH value.
Source failure-count field: 0.
Turbidity
✓ No exceedances reported
Published mean
<0.10 NTU
Source reference: 4 NTU
Measures cloudiness caused by suspended particles. It cannot identify their cause on its own.
36 samples · Range: <0.10 to 0.13 NTU
The source reports 0 failures across 36 samples. This describes the published period.
“<” is part of the source result. It is not an exact concentration or a measured zero.
Original wording and source notes
Source reference: 4. Source parameter: Turbidity. Original mean: <0.10 NTU.
Source failure-count field: 0.
Conductivity
✓ No exceedances reported
Published mean
548 μS/cm at 20 °C
Source reference: 2500 μS/cm at 20 °C
Indicates how readily water conducts electricity, influenced by dissolved ions. It is not a direct measurement of hardness or safety.
36 samples · Range: 479 to 599 μS/cm at 20 °C
The source reports 0 failures across 36 samples. This describes the published period.
Original wording and source notes
Source reference: 2500. Source parameter: Electrical Conductivity at 20 °C. Original mean: 548 μS/cm at 20 °C.
Source failure-count field: 0.
Total organic carbon
✓ No exceedances reported
Published mean
<0.4 mgC/l
Source reference: No abnormal change
A broad measure of organic carbon used to understand water and treatment. It does not identify an individual contaminant.
8 samples · Range: <0.4 to 0.4 mgC/l
The source reports 0 failures across 8 samples. This describes the published period.
“<” is part of the source result. It is not an exact concentration or a measured zero.
Original wording and source notes
Source reference: No abnormal change. Source parameter: Total Organic Carbon. Original mean: <0.4 mgC/l.
Source failure-count field: 0.
Metals 13 parameters
Arsenic
✓ No exceedances reported
Published mean
0.2 μgAs/l
Source reference: 10 μgAs/l
A trace element monitored against a drinking-water requirement. Use the source results and units rather than taste or appearance to interpret it.
8 samples · Range: <0.1 to 0.2 μgAs/l
The source reports 0 failures across 8 samples. This describes the published period.
Original wording and source notes
Source reference: 10. Source parameter: Arsenic. Original mean: 0.2 μgAs/l.
Source failure-count field: 0.
Aluminium
✓ No exceedances reported
Published mean
2.3 μgAl/l
Source reference: 200 μgAl/l
Monitored as part of water-quality testing and treatment control. Compare with the reference and sample results in the source.
8 samples · Range: <2.0 to 18.5 μgAl/l
The source reports 0 failures across 8 samples. This describes the published period.
Original wording and source notes
Source reference: 200. Source parameter: Aluminium. Original mean: 2.3 μgAl/l.
Source failure-count field: 0.
Antimony
✓ No exceedances reported
Published mean
<0.03 μgSb/l
Source reference: 5 μgSb/l
A trace element monitored in drinking water. The source reference and sample results provide the relevant comparison.
8 samples · Range: <0.03 to 0.06 μgSb/l
The source reports 0 failures across 8 samples. This describes the published period.
“<” is part of the source result. It is not an exact concentration or a measured zero.
Original wording and source notes
Source reference: 5. Source parameter: Antimony. Original mean: <0.03 μgSb/l.
Source failure-count field: 0.
Cadmium
✓ No exceedances reported
Published mean
<0.05 μgCd/l
Source reference: 5 μgCd/l
A trace metal monitored in drinking water. A less-than result reports an upper bound, not a measured zero.
8 samples · Range: <0.05 to <0.05 μgCd/l
The source reports 0 failures across 8 samples. This describes the published period.
“<” is part of the source result. It is not an exact concentration or a measured zero.
Original wording and source notes
Source reference: 5. Source parameter: Cadmium. Original mean: <0.05 μgCd/l.
Source failure-count field: 0.
Chromium
✓ No exceedances reported
Published mean
<0.4 μgCr/l
Source reference: 50 μgCr/l
A trace metal monitored in drinking-water reports. Keep the source’s chemical definition and units when comparing results.
8 samples · Range: <0.2 to 0.4 μgCr/l
The source reports 0 failures across 8 samples. This describes the published period.
“<” is part of the source result. It is not an exact concentration or a measured zero.
Original wording and source notes
Source reference: 50. Source parameter: Chromium. Original mean: <0.4 μgCr/l.
Source failure-count field: 0.
Copper
✓ No exceedances reported
Published mean
0.186 mgCu/l
Source reference: 2 mgCu/l
Can be influenced by plumbing. The area report does not replace investigation of a problem at an individual property.
8 samples · Range: 0.005 to 1.13 mgCu/l
The source reports 0 failures across 8 samples. This describes the published period.
Original wording and source notes
Source reference: 2. Source parameter: Copper. Original mean: 0.186 mgCu/l.
Source failure-count field: 0.
Iron
✓ No exceedances reported
Published mean
<9.0 μgFe/l
Source reference: 200 μgFe/l
Can affect water colour, staining and taste. A historical result does not diagnose a change in your tap water today.
8 samples · Range: <3.3 to <9.0 μgFe/l
The source reports 0 failures across 8 samples. This describes the published period.
“<” is part of the source result. It is not an exact concentration or a measured zero.
Original wording and source notes
Source reference: 200. Source parameter: Iron. Original mean: <9.0 μgFe/l.
Source failure-count field: 0.
Lead
✓ No exceedances reported
Published mean
1.05 μgPb/l
Source reference: 10 μgPb/l
Plumbing can affect lead at an individual tap. An area average cannot rule out a problem with pipes at your property.
8 samples · Range: <0.67 to 3.93 μgPb/l
The source reports 0 failures across 8 samples. This describes the published period.
Original wording and source notes
Source reference: 10. Source parameter: Lead. Original mean: 1.05 μgPb/l.
Source failure-count field: 0.
Manganese
✓ No exceedances reported
Published mean
<0.4 μgMn/l
Source reference: 50 μgMn/l
Can affect colour and deposits. Any reported exceedance needs the supplier’s investigation context.
8 samples · Range: <0.4 to 0.5 μgMn/l
The source reports 0 failures across 8 samples. This describes the published period.
“<” is part of the source result. It is not an exact concentration or a measured zero.
Original wording and source notes
Source reference: 50. Source parameter: Manganese. Original mean: <0.4 μgMn/l.
Source failure-count field: 0.
Mercury
✓ No exceedances reported
Published mean
<0.02 μgHg/l
Source reference: 1 μgHg/l
A trace metal monitored against drinking-water requirements. Keep detection limits separate from exact measurements.
8 samples · Range: <0.02 to <0.02 μgHg/l
The source reports 0 failures across 8 samples. This describes the published period.
“<” is part of the source result. It is not an exact concentration or a measured zero.
Original wording and source notes
Source reference: 1. Source parameter: Mercury. Original mean: <0.02 μgHg/l.
Source failure-count field: 0.
Nickel
✓ No exceedances reported
Published mean
2.9 μgNi/l
Source reference: 20 μgNi/l
A monitored metal that can be influenced by materials in contact with water. Local plumbing and sampling context matter.
8 samples · Range: <0.6 to 17.6 μgNi/l
The source reports 0 failures across 8 samples. This describes the published period.
Original wording and source notes
Source reference: 20. Source parameter: Nickel. Original mean: 2.9 μgNi/l.
Source failure-count field: 0.
Boron
✓ No exceedances reported
Published mean
<0.046 mgB/l
Source reference: 1 mgB/l
A dissolved element monitored in drinking water. The source reference applies to the parameter and units shown here.
8 samples · Range: <0.045 to <0.046 mgB/l
The source reports 0 failures across 8 samples. This describes the published period.
“<” is part of the source result. It is not an exact concentration or a measured zero.
Original wording and source notes
Source reference: 1. Source parameter: Boron. Original mean: <0.046 mgB/l.
Source failure-count field: 0.
Selenium
✓ No exceedances reported
Published mean
<0.4 μgSe/l
Source reference: 10 μgSe/l
A trace element monitored in drinking water. Its presence alone does not establish that a requirement was exceeded.
8 samples · Range: <0.4 to 0.6 μgSe/l
The source reports 0 failures across 8 samples. This describes the published period.
“<” is part of the source result. It is not an exact concentration or a measured zero.
Original wording and source notes
Source reference: 10. Source parameter: Selenium. Original mean: <0.4 μgSe/l.
Source failure-count field: 0.
Microbiology 5 parameters
Coliform bacteria
✓ No exceedances reported
Published mean
0 No./100ml
Source reference: 0 No./100ml
Used to monitor water-system hygiene. Interpret detections with the supplier’s sampling location and investigation notes.
84 samples · Range: 0 to 0 No./100ml
The source reports 0 failures across 84 samples. This describes the published period.
Original wording and source notes
Source reference: 0. Source parameter: Coliform bacteria. Original mean: 0 No./100ml.
Source failure-count field: 0.
E. coli
✓ No exceedances reported
Published mean
0 No./100ml
Source reference: 0 No./100ml
A microbiological indicator. The reported sample results and any failures matter more than an average bacterial count.
84 samples · Range: 0 to 0 No./100ml
The source reports 0 failures across 84 samples. This describes the published period.
Original wording and source notes
Source reference: 0. Source parameter: E coli. Original mean: 0 No./100ml.
Source failure-count field: 0.
Clostridium perfringens
✓ No exceedances reported
Published mean
0 No./100ml
Source reference: 0 No./100ml
A microbiological indicator used in water-quality monitoring. Check the sample results and source investigation context.
8 samples · Range: 0 to 0 No./100ml
The source reports 0 failures across 8 samples. This describes the published period.
Original wording and source notes
Source reference: 0. Source parameter: Clostridium perfringens. Original mean: 0 No./100ml.
Source failure-count field: 0.
Enterococci
✓ No exceedances reported
Published mean
0 No./100ml
Source reference: 0 No./100ml
A microbiological indicator assessed through sample results. Read any reported failures with the supplier’s investigation notes.
8 samples · Range: 0 to 0 No./100ml
The source reports 0 failures across 8 samples. This describes the published period.
Original wording and source notes
Source reference: 0. Source parameter: Enterococci. Original mean: 0 No./100ml.
Source failure-count field: 0.
Colony count at 22°C
✓ No exceedances reported
Published mean
0 No./1ml at 22 °C
Source reference: No abnormal change
A general bacterial count used to monitor changes in the supply. It is not equivalent to an E. coli result.
36 samples · Range: 0 to 2 No./1ml at 22 °C
The source reports 0 failures across 36 samples. This describes the published period.
Original wording and source notes
Source reference: No abnormal change. Source parameter: 3 day plate count 22 °C. Original mean: 0 No./1ml at 22 °C.
Source failure-count field: 0.
Other monitored substances 15 parameters
Temperature
No numerical limit supplied
Published mean
14.2 °C
Source reference: No numerical limit supplied
About this parameter: see the note above this list.
84 samples · Range: 7.7 to 23.5 °C
This report gives no numerical limit for this parameter. A higher or lower number is not automatically better.
Original wording and source notes
Source reference: No PCV. Source parameter: Temperature. Original mean: 14.2 °C.
Source failure-count field: 0.
Atrazine
✓ No exceedances reported
Published mean
<0.011 μg/l
Source reference: 0.1 μg/l
About this parameter: see the note above this list.
8 samples · Range: <0.011 to <0.011 μg/l
The source reports 0 failures across 8 samples. This describes the published period.
“<” is part of the source result. It is not an exact concentration or a measured zero.
Original wording and source notes
Source reference: 0.1. Source parameter: Atrazine. Original mean: <0.011 μg/l.
Source failure-count field: 0.
Total Pesticide
✓ No exceedances reported
Published mean
0.007 μg/l
Source reference: 0.5 μg/l
About this parameter: see the note above this list.
8 samples · Range: 0.005 to 0.011 μg/l
The source reports 0 failures across 8 samples. This describes the published period.
Original wording and source notes
Source reference: 0.5. Source parameter: Total Pesticide. Original mean: 0.007 μg/l.
Source failure-count field: 0.
Ammonium
✓ No exceedances reported
Published mean
<0.06 mgNH4/l
Source reference: 0.5 mgNH4/l
About this parameter: see the note above this list.
8 samples · Range: <0.05 to <0.06 mgNH4/l
The source reports 0 failures across 8 samples. This describes the published period.
“<” is part of the source result. It is not an exact concentration or a measured zero.
Original wording and source notes
Source reference: 0.5. Source parameter: Ammonium. Original mean: <0.06 mgNH4/l.
Source failure-count field: 0.
Benzene
✓ No exceedances reported
Published mean
<0.18 μg/l
Source reference: 1 μg/l
About this parameter: see the note above this list.
8 samples · Range: <0.17 to <0.18 μg/l
The source reports 0 failures across 8 samples. This describes the published period.
“<” is part of the source result. It is not an exact concentration or a measured zero.
Original wording and source notes
Source reference: 1. Source parameter: Benzene. Original mean: <0.18 μg/l.
Source failure-count field: 0.
Benzo (a) Pyrene
✓ No exceedances reported
Published mean
<0.001 μg/l
Source reference: 0.01 μg/l
About this parameter: see the note above this list.
8 samples · Range: <0.001 to <0.001 μg/l
The source reports 0 failures across 8 samples. This describes the published period.
“<” is part of the source result. It is not an exact concentration or a measured zero.
Original wording and source notes
Source reference: 0.01. Source parameter: Benzo (a) Pyrene. Original mean: <0.001 μg/l.
Source failure-count field: 0.
Bromate
✓ No exceedances reported
Published mean
<1.5 μgBrO3/l
Source reference: 10 μgBrO3/l
About this parameter: see the note above this list.
8 samples · Range: <1.5 to <1.5 μgBrO3/l
The source reports 0 failures across 8 samples. This describes the published period.
“<” is part of the source result. It is not an exact concentration or a measured zero.
Original wording and source notes
Source reference: 10. Source parameter: Bromate. Original mean: <1.5 μgBrO3/l.
Source failure-count field: 0.
Nitrate
✓ No exceedances reported
Published mean
23.7 mgNO3/l
Source reference: 50 mgNO3/l
A dissolved compound monitored against drinking-water requirements. Its mean, highest reported result and sample count answer different questions.
8 samples · Range: 17.8 to 26.4 mgNO3/l
The source reports 0 failures across 8 samples. This describes the published period.
Original wording and source notes
Source reference: 50. Source parameter: Nitrate. Original mean: 23.7 mgNO3/l.
Source failure-count field: 0.
Nitrite
✓ No exceedances reported
Published mean
<0.010 mgNO2/l
Source reference: 0.5 mgNO2/l
A nitrogen compound monitored in water supplies. Requirements can depend on where the sample was collected; use the reference printed in this report.
8 samples · Range: <0.007 to <0.010 mgNO2/l
The source reports 0 failures across 8 samples. This describes the published period.
“<” is part of the source result. It is not an exact concentration or a measured zero.
Original wording and source notes
Source reference: 0.5. Source parameter: Nitrite. Original mean: <0.010 mgNO2/l.
Source failure-count field: 0.
Sum of Tri & Tetrachloroethene
✓ No exceedances reported
Published mean
0 μg/l
Source reference: 10 μg/l
About this parameter: see the note above this list.
8 samples · Range: 0 to 0 μg/l
The source reports 0 failures across 8 samples. This describes the published period.
Original wording and source notes
Source reference: 10. Source parameter: Sum of Tri & Tetrachloroethene. Original mean: 0 μg/l.
Source failure-count field: 0.
Tetrachloromethane
✓ No exceedances reported
Published mean
<0.2 μg/l
Source reference: 3 μg/l
About this parameter: see the note above this list.
8 samples · Range: <0.2 to <0.2 μg/l
The source reports 0 failures across 8 samples. This describes the published period.
“<” is part of the source result. It is not an exact concentration or a measured zero.
Original wording and source notes
Source reference: 3. Source parameter: Tetrachloromethane. Original mean: <0.2 μg/l.
Source failure-count field: 0.
Total Cyanide
✓ No exceedances reported
Published mean
<6.5 μgCN/l
Source reference: 50 μgCN/l
About this parameter: see the note above this list.
8 samples · Range: <6.5 to <6.5 μgCN/l
The source reports 0 failures across 8 samples. This describes the published period.
“<” is part of the source result. It is not an exact concentration or a measured zero.
Original wording and source notes
Source reference: 50. Source parameter: Total Cyanide. Original mean: <6.5 μgCN/l.
Source failure-count field: 0.
Total PAHs
✓ No exceedances reported
Published mean
0 μg/l
Source reference: 0.1 μg/l
About this parameter: see the note above this list.
8 samples · Range: 0 to 0 μg/l
The source reports 0 failures across 8 samples. This describes the published period.
Original wording and source notes
Source reference: 0.1. Source parameter: Total PAHs. Original mean: 0 μg/l.
Source failure-count field: 0.
Total Trihalomethanes
✓ No exceedances reported
Published mean
2.5 μg/l
Source reference: 100 μg/l
About this parameter: see the note above this list.
8 samples · Range: 0.77 to 4.44 μg/l
The source reports 0 failures across 8 samples. This describes the published period.
Original wording and source notes
Source reference: 100. Source parameter: Total Trihalomethanes. Original mean: 2.5 μg/l.
Source failure-count field: 0.
1, 2 dichloroethane
✓ No exceedances reported
Published mean
<0.15 μg/l
Source reference: 3 μg/l
About this parameter: see the note above this list.
8 samples · Range: <0.15 to <0.15 μg/l
The source reports 0 failures across 8 samples. This describes the published period.
“<” is part of the source result. It is not an exact concentration or a measured zero.
Original wording and source notes
Source reference: 3. Source parameter: 1, 2 dichloroethane. Original mean: <0.15 μg/l.
Source failure-count field: 0.
Sources, dates and how to interpret this page
- Reporting period
- 2025
- Source retrieved
- 2026-02-26
- Last verified source check
- 2026-09-20
- Original publication
- Affinity Water report ↗
Published area statistics are not a test at your home or a current incident report.
Hardness: 1 sample · reported range 305 to 305 mgCaCO3/l.
Affinity’s live hardness summary can differ from its annual report. Check the reporting periods before treating a difference as a trend.
Status labels describe the published parameter and period. Historical exceedances do not automatically establish a current incident. Numerical limits are taken from the original report, not applied indiscriminately across countries, dates or sampling locations. DWI explains how standards work in England and Wales.
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