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Knebworth/Tewin · East Hertfordshire
Affinity Water
Water safety
Water safety| Parameter | Unfiltered tap water | Allowed range | Filtered |
|---|
| Free Chlorinemg CL2/l | Not reported | 0.2 – 1 | — |
|---|
| Total Chlorinemg CL2/l | 0.37 | No limit | 0.074 |
|---|
General
General| Parameter | Unfiltered tap water | Allowed range | Filtered |
|---|
| TemperatureC | 14.7 | No limit | 14.7 |
|---|
| Hardnessmg CaCO3/l | 295 | 80 – 459 | 295 |
|---|
| pH | 7.5 | 6.5 – 9.5 | 7.5 |
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| TurbidityNTU | 0.1 | ≤ 4 | 0.01 |
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| ColorColor Units | 2 | ≤ 15 | 2 |
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| ConductivityμS / cm | 698 | ≤ 2,500 | 698 |
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| TDSmg/l | 446.7estimated | 0 – 1,199 | 446.7 |
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| OdorTON | 0 | ≤ 3 | 0 |
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| Alkalinitymg CaCO3/l | 243.6 | No limit | 243.6 |
|---|
Pathogens
Pathogens| Parameter | Unfiltered tap water | Allowed range | Filtered |
|---|
| ClostridiumUFC/100ml | 0 | ≤ 0 | 0 |
|---|
| eColiUFC/100ml | 0 | ≤ 0 | 0 |
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| BacteriasNMP/100ml | 0 | ≤ 0 | 0 |
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| EnterococcusUFC/100ml | 0 | ≤ 0 | 0 |
|---|
Chemical parameters
Chemical parameters| Parameter | Unfiltered tap water | Allowed range | Filtered |
|---|
| Cyanide totalμg CN/l | 6.5 | ≤ 50 | 0.33 |
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| Fluoridemg F/l | 0.23 | ≤ 1.5 | 0.068 |
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| Mercuryμg Hg/l | 0.02 | ≤ 1 | 0.002 |
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| Nitritesmg NO2/l | 0.01 | ≤ 0.5 | 0.004 |
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| Nitratesmg NO3/l | 26.7 | ≤ 50 | 8.01 |
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Minerals
Minerals| Parameter | Unfiltered tap water | Allowed range | Filtered |
|---|
| Calciummg/l | 118 | No limit | 118 |
|---|
| Chloridemg/l | 57 | ≤ 250 | 57 |
|---|
Metals
Metals| Parameter | Unfiltered tap water | Allowed range | Filtered |
|---|
| Aluminiumμg/l | 2 | ≤ 200 | 2 |
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| Antimonyμg/l | 0.29 | ≤ 5 | 0.29 |
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| Arsenicμg/l | 0.3 | ≤ 10 | 0.15 |
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| Cadmiumμg/l | 0.05 | ≤ 5 | 0.05 |
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| Chromiumμg/l | 0.4 | ≤ 50 | 0.4 |
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| Copperμg/l | 22 | ≤ 2,000 | 1.1 |
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| Ironμg/l | 9 | ≤ 200 | 9 |
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| Manganeseμg/l | 0.4 | ≤ 50 | 0.4 |
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| Leadμg/l | 0.67 | ≤ 10 | 0.034 |
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| Nickelμg/l | 2.3 | ≤ 20 | 2.3 |
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| Seleniumμg/l | 0.4 | ≤ 10 | 0.4 |
|---|
| Sodiummg/l | 61.4 | ≤ 200 | 61.4 |
|---|
Chlorine by-products
Chlorine by-products| Parameter | Unfiltered tap water | Allowed range | Filtered |
|---|
| Total Trichloroethyleneμg/l | 0 | ≤ 10 | 0 |
|---|
| Total Trihalomethanesμg/l | 29.6 | ≤ 100 | 1.48 |
|---|
Pesticides
Pesticides| Parameter | Unfiltered tap water | Allowed range | Filtered |
|---|
| Total pesticidesug/L | 0.027 | ≤ 0.5 | 0.027 |
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Herbicides
Herbicides| Parameter | Unfiltered tap water | Allowed range | Filtered |
|---|
| D 2 4ug/L | 0.008 | ≤ 70 | 0.008 |
|---|
| Atrazineug/L | 0.011 | ≤ 3 | 0.011 |
|---|
Perfluorinated chemicals
Perfluorinated chemicals| Parameter | Unfiltered tap water | Allowed range | Filtered |
|---|
| Total PFASug/L | Not reported | ≤ 0.1 | — |
|---|
| PFAS 4ng/l | Not reported | No limit | — |
|---|
| PFAS 21ng/l | Not reported | No limit | — |
|---|
Other
Other| Parameter | Unfiltered tap water | Allowed range | Filtered |
|---|
| Ammoniamg/l | 0.06 | No limit | 0.018 |
|---|
| Sulfatemg/l | 96 | No limit | 96 |
|---|
Data collected from the water company for your area. Quality ranges are based on WHO guidelines and the UK drinking water regulations.
668 of 668 tests within UK limits
