Drinking water in Hilden, Düsseldorf
3 supply zones — values can differ depending on the district. Below is the zone with the most documented parameters, the others collapsed underneath. To determine the exact match, look up the postcode.
How to read the share of the parametric value
12 % Share of the parametric value. The proportion of the permitted maximum that the measured value uses — here 12 %, so just over an eighth.
< 10 % * Below the limit of quantification. The substance was not detectable. The mark shows where the detection limit lies relative to the parametric value — the actual share of the parametric value is below that.
Several samples per year: for chemical parameters the mean value is given, for microbiological ones the highest measured value. There the parametric value is zero — a single finding would disappear in the average, and it is precisely that finding which is the information. Which reference applies is stated in the last column of the table.
Hochbehälter Hardt (Düsseldorf und Mettmann)
Stadtwerke DüsseldorfWater hardness
14.7 °dH
Hardness range hart
| Parameter | Value | Parametric value | Share of the parametric value | Reference |
|---|---|---|---|---|
| Sum of PFAS | 0,001 µg/l | — | — | Single value |
| Nitrate | 13,1 mg/l | 50 mg/l | 26 % | Single value |
| Lead | <0,002 mg/l below limit of quantification | 10 µg/l | < 20 % * | Single value |
| Escherichia coli (E. coli) | 0 MPN/100 ml | 0/100 ml | — | Single value |
| Sulphate | 58,2 mg/l | 250 mg/l | 23 % | Single value |
| Sodium | 28,5 mg/l | 200 mg/l | 14 % | Single value |
* Value below the limit of quantification: the actual share of the parametric value is not known; it lies somewhere below the stated upper bound. The marker shows where the limit of quantification of the measurement lies relative to the parametric value.
Show all recorded parameters (64 — most recent value per parameter)
Microbiology (2)
| Parameter | Value | Parametric value | Share of the parametric value | Reference |
|---|---|---|---|---|
| Escherichia coli (E. coli) | 0 MPN/100 ml | 0/100 ml | — | Single value |
| Intestinal enterococci | 0 KBE/100 ml | 0/100 ml | — | Single value |
Chemical parameters (24)
| Parameter | Value | Parametric value | Share of the parametric value | Reference |
|---|---|---|---|---|
| 1,2-dichloroethane | <0,2 µg/l below limit of quantification | 3 µg/l | < 7 % * | Single value |
| Antimony | <0,0008 mg/l below limit of quantification | 5 µg/l | < 16 % * | Single value |
| Arsenic | <0,0009 mg/l below limit of quantification | 10 µg/l | < 9 % * | Single value |
| Benzene | <0,2 µg/l below limit of quantification | 1 µg/l | < 20 % * | Single value |
| Benzo(a)pyrene | <0,002 µg/l below limit of quantification | 10 ng/l | < 20 % * | Single value |
| Bisphenol A | <0,05 µg/l below limit of quantification | 2.5 µg/l | < 2 % * | Single value |
| Boron | <0,060 mg/l below limit of quantification | 1 mg/l | < 6 % * | Single value |
| Bromate | 0,001 mg/l | 10 µg/l | 10 % | Single value |
| Cadmium | <0,0004 mg/l below limit of quantification | 3 µg/l | < 13 % * | Single value |
| Chromium | <0,001 mg/l below limit of quantification | 25 µg/l | < 4 % * | Single value |
| Copper | <0,030 mg/l below limit of quantification | 2 mg/l | < 2 % * | Single value |
| Fluoride | 0,13 mg/l | 1.5 mg/l | 9 % | Single value |
| Lead | <0,002 mg/l below limit of quantification | 10 µg/l | < 20 % * | Single value |
| Mercury | <0,00001 mg/l below limit of quantification | 1 µg/l | < 1 % * | Single value |
| Nickel | <0,002 mg/l below limit of quantification | 20 µg/l | < 10 % * | Single value |
| Nitrate | 13,1 mg/l | 50 mg/l | 26 % | Single value |
| Nitrite | <0,01 mg/l below limit of quantification | 0.5 mg/l | < 2 % * | Single value |
| Pesticides — Total | <0,01 µg/l below limit of quantification | 0.5 µg/l | < 2 % * | Single value |
| Polycyclic aromatic hydrocarbons | 0 µg/l | 0.1 µg/l | 0 % | Single value |
| Selenium | <0,002 mg/l below limit of quantification | 10 µg/l | < 20 % * | Single value |
| Tetrachloroethene and Trichloroethene (sum) | <0,2 µg/l below limit of quantification | 10 µg/l | < 2 % * | Single value |
| Trihalomethanes — Total | 0 µg/l | 50 µg/l | 0 % | Single value |
| Uranium | 0,0006 mg/l | 10 µg/l | 6 % | Single value |
| Vinyl chloride | <0,2 µg/l below limit of quantification | 0.5 µg/l | < 40 % * | Single value |
* Value below the limit of quantification: the actual share of the parametric value is not known; it lies somewhere below the stated upper bound. The marker shows where the limit of quantification of the measurement lies relative to the parametric value.
PFAS (3)
| Parameter | Value | Parametric value | Share of the parametric value | Reference |
|---|---|---|---|---|
| Sum of 4 PFAS | 0 µg/l | — | — | Single value |
| Sum of PFAS | 0,001 µg/l | — | — | Single value |
| Trifluoroacetic acid (TFA) | 0,50 µg/L | 60 µg/l UBA guide value | 0.8 % | Single value |
For trifluoroacetic acid (TFA), the German Drinking Water Ordinance does not specify a parametric value. The comparison is therefore made with the guide value of 60 µg/l issued by the Umweltbundesamt, which has replaced the earlier health-related guidance value of 3 µg/l. A guide value is not a legal maximum but a health-related classification.
Indicator parameters (20)
| Parameter | Value | Parametric value | Share of the parametric value | Reference |
|---|---|---|---|---|
| Aluminium | <0,030 mg/l below limit of quantification | 0.2 mg/l | < 15 % * | Single value |
| Ammonium | <0,03 mg/l below limit of quantification | 0.5 mg/l | < 6 % * | Single value |
| Calcite dissolution capacity | -6,10 mg/l CaCO3 | 5 mg/l CaCO3 | — | Single value |
| Chloride | 67,9 mg/l | 250 mg/l | 27 % | Single value |
| Clostridium perfringens (including spores) | 0 KBE/100 ml | 0/100 ml | — | Single value |
| Coliform bacteria | 0 MPN/100 ml | 0/100 ml | — | Single value |
| Colony count 22 °C | 1 KBE/ml | ohne anormale Veränderung | — | Single value |
| Colony count 36 °C | 1 KBE/ml | ohne anormale Veränderung | — | Single value |
| Colour | <0,1 1/m below limit of quantification | 0.5 m⁻¹ | — | Single value |
| Conductivity (25 °C) | 699 µS/cm | 2,790 µS/cm | — | Single value |
| Iron | <0,020 mg/l below limit of quantification | 0.2 mg/l | < 10 % * | Single value |
| Manganese | <0,020 mg/l below limit of quantification | 50 µg/l | < 40 % * | Single value |
| Odour | erfüllt - | für den Verbraucher annehmbar | — | Single value |
| pH | 7,50 pH-Einheiten | 6,5–9,5 | — | Single value |
| Sodium | 28,5 mg/l | 200 mg/l | 14 % | Single value |
| Sulphate | 58,2 mg/l | 250 mg/l | 23 % | Single value |
| Taste | erfüllt - | für den Verbraucher annehmbar | — | Single value |
| Temperature | 14,00 °C | — | — | Single value |
| Total organic carbon (TOC) | 0,28 mg/l | ohne anormale Veränderung | — | Single value |
| Turbidity | 0,12 FNU | 1 NTU | — | Single value |
* Value below the limit of quantification: the actual share of the parametric value is not known; it lies somewhere below the stated upper bound. The marker shows where the limit of quantification of the measurement lies relative to the parametric value.
Radiology (2)
| Parameter | Value | Parametric value | Share of the parametric value | Reference |
|---|---|---|---|---|
| Gross alpha activity | < 0,025 Bq/l below limit of quantification | — | — | Single value |
| Radon-222 | < 10 Bq/l below limit of quantification | 100 Bq/l | — | Single value |
Further parameters (13)
| Parameter | Value | Parametric value | Share of the parametric value | Reference |
|---|---|---|---|---|
| Acid capacity to pH 4.3 | 2,00 mmol/l | — | — | Single value |
| Barium | 0,052 mg/l | — | — | Single value |
| Base capacity to pH 8.2 | 0,10 mmol/l | — | — | Single value |
| Bromide | 0,12 mg/l | — | — | Single value |
| Calcium | 1,62 mmol/l | — | — | Single value |
| Hardness range (WRMG) | hart | — | — | Single value |
| Magnesium | 0,36 mmol/l | — | — | Single value |
| Phosphate | <0,07 mg/l below limit of quantification | — | — | Single value |
| Potassium | 3,30 mg/l | — | — | Single value |
| Strontium | 0,453 mg/l | — | — | Single value |
| Thallium | <0,002 mg/l below limit of quantification | — | — | Single value |
| Total hardness | 2,62 mmol/l | — | — | Single value |
| Zinc | <0,010 mg/l below limit of quantification | — | — | Single value |
Values taken unchanged from the publications linked below — for each parameter the most recent recorded value. „—" in the parametric value column: no currently valid legal parametric value is stored in our database for this parameter; the parameter register with all parametric values is being expanded continuously.
Source: https://a.storyblok.com/f/274772/x/9e9ba42c93/trinkwasseranalyse-duesseldorf-2026.pdf · 01.01.2025-31.12.2025 (Hochbehälter Hardt); Radioaktivitätsparameter: 04.06.2018-31.07.2018 · retrieved on 11/07/2026
Postcodes in this zone: 40721
Show 2 more supply zones
Baumberg
Stadtwerke HildenAssigned via the water supplier — the exact supply zone boundary within the postcode is not yet linked.
| Parameter | Value | Parametric value | Share of the parametric value | Reference |
|---|---|---|---|---|
| Sum of PFAS | 0,000.042 mg/l | — | — | Mean |
| Nitrate | 15,5 mg/l | 50 mg/l | 31 % | Mean |
| Lead | <0,001 mg/l below limit of quantification | 10 µg/l | < 10 % * | Mean |
| Escherichia coli (E. coli) | 0 Anzahl/100ml | 0/100 ml | — | Mean |
| Sulphate | 50,7 mg/l | 250 mg/l | 20 % | Mean |
| Sodium | 27,1 mg/l | 200 mg/l | 14 % | Mean |
* Value below the limit of quantification: the actual share of the parametric value is not known; it lies somewhere below the stated upper bound. The marker shows where the limit of quantification of the measurement lies relative to the parametric value.
Show all recorded parameters (64 — most recent value per parameter)
Microbiology (2)
| Parameter | Value | Parametric value | Share of the parametric value | Reference |
|---|---|---|---|---|
| Escherichia coli (E. coli) | 0 Anzahl/100ml | 0/100 ml | — | Mean |
| Intestinal enterococci | 0 Anzahl/100ml | 0/100 ml | — | Mean |
Chemical parameters (32)
| Parameter | Value | Parametric value | Share of the parametric value | Reference |
|---|---|---|---|---|
| 1,2-dichloroethane | <0,000.5 mg/l below limit of quantification | 3 µg/l | — | Mean |
| Acrylamide | n.e.3.) mg/l not determined | 0.1 µg/l | — | Mean |
| Antimony | <0,001 mg/l below limit of quantification | 5 µg/l | < 20 % * | Mean |
| Arsenic | <0,001 mg/l below limit of quantification | 10 µg/l | < 10 % * | Mean |
| Benzene | <0,000.2 mg/l below limit of quantification | 1 µg/l | — | Mean |
| Benzo(a)pyrene | <0,000.0025 mg/l below limit of quantification | 10 ng/l | — | Mean |
| Bisphenol A | <0,001 Mg/l below limit of quantification | 2.5 µg/l | < 40 % * | Mean |
| Boron | 0.052 mg/l | 1 mg/l | 5 % | Mean |
| Bromate | <0,0025 mg/l below limit of quantification | 10 µg/l | < 25 % * | Mean |
| Cadmium | <0,000.2 mg/l below limit of quantification | 3 µg/l | — | Mean |
| Chlorate | n.e. 3.) mg/l not determined | 70 µg/l | — | Mean |
| Chlorite | n.e. 3.) mg/l not determined | 0.2 mg/l | — | Mean |
| Chromium | <0,0005 mg/l below limit of quantification | 25 µg/l | < 2 % * | Mean |
| Copper | <0,001 mg/l below limit of quantification | 2 mg/l | < < 0.1 % * | Mean |
| Cyanide | <0,005 mg/l below limit of quantification | 50 µg/l | < 10 % * | Mean |
| Epichlorohydrin | n.e. 3.) mg/l not determined | 0.1 µg/l | — | Mean |
| Fluoride | 0,06 mg/l | 1.5 mg/l | 4 % | Mean |
| Haloacetic acids (HAA) | n.e. 3.) mg/l not determined | — | — | Mean |
| Lead | <0,001 mg/l below limit of quantification | 10 µg/l | < 10 % * | Mean |
| Mercury | <0,000.1 mg/l below limit of quantification | 1 µg/l | — | Mean |
| Microcystin-LR | n.e. mg/l not determined | — | — | Mean |
| Nickel | 0,002 mg/l | 20 µg/l | 10 % | Mean |
| Nitrate | 15,5 mg/l | 50 mg/l | 31 % | Mean |
| Nitrite | <0,001 mg/l below limit of quantification | 0.5 mg/l | < 0.2 % * | Mean |
| Pesticides | n.b.4.) mg/l not determined | 0.1 µg/l | — | Mean |
| Pesticides — Total | n.b.4.) mg/l not determined | 0.5 µg/l | — | Mean |
| Polycyclic aromatic hydrocarbons | n.b.4.) mg/l not determined | 0.1 µg/l | — | Mean |
| Selenium | <0,001 mg/l below limit of quantification | 10 µg/l | < 10 % * | Mean |
| Tetrachloroethene and Trichloroethene (sum) | n.b.4.) mg/l not determined | 10 µg/l | — | Mean |
| Trihalomethanes — Total | n.b.4.) mg/l not determined | 50 µg/l | — | Mean |
| Uranium | <0,001 mg/l below limit of quantification | 10 µg/l | < 10 % * | Mean |
| Vinyl chloride | <0,000.5 mg/l below limit of quantification | 0.5 µg/l | — | Mean |
* Value below the limit of quantification: the actual share of the parametric value is not known; it lies somewhere below the stated upper bound. The marker shows where the limit of quantification of the measurement lies relative to the parametric value.
PFAS (1)
| Parameter | Value | Parametric value | Share of the parametric value | Reference |
|---|---|---|---|---|
| Sum of PFAS | 0,000.042 mg/l | — | — | Mean |
Indicator parameters (19)
| Parameter | Value | Parametric value | Share of the parametric value | Reference |
|---|---|---|---|---|
| Aluminium | <0,005 mg/l below limit of quantification | 0.2 mg/l | < 3 % * | Mean |
| Ammonium | <0,02 mg/l below limit of quantification | 0.5 mg/l | < 4 % * | Mean |
| Calcite dissolution capacity | 0,9 mg/l CaCO3 | 5 mg/l CaCO3 | — | Mean |
| Chloride | 28,4 mg/l | 250 mg/l | 11 % | Mean |
| Clostridium perfringens (including spores) | 0 Anzahl/100ml | 0/100 ml | — | Mean |
| Coliform bacteria | 0 Anzahl/100ml | 0/100 ml | — | Mean |
| Colour | <0,10 m -1 below limit of quantification | 0.5 m⁻¹ | — | Mean |
| Conductivity (25 °C) | 503 µS/cm | 2,790 µS/cm | — | Mean |
| Iron | <0,010 mg/l below limit of quantification | 0.2 mg/l | < 5 % * | Mean |
| Manganese | <0,001 mg/l below limit of quantification | 50 µg/l | < 2 % * | Mean |
| Odour | unauffällig - | für den Verbraucher annehmbar | — | Mean |
| Oxidisability | n.e. 3.) mg/l O2 not determined | 5 mg/l O2 | — | Mean |
| pH | 7,57 - | 6,5–9,5 | — | Mean |
| Sodium | 27,1 mg/l | 200 mg/l | 14 % | Mean |
| Sulphate | 50,7 mg/l | 250 mg/l | 20 % | Mean |
| Taste | unauffällig - | für den Verbraucher annehmbar | — | Mean |
| Temperature | 11,4 - 12,8 °C | — | — | Single value |
| Total organic carbon (TOC) | 1,4 mg/l | ohne anormale Veränderung | — | Mean |
| Turbidity | <0,03 FNU below limit of quantification | 1 NTU | — | Mean |
* Value below the limit of quantification: the actual share of the parametric value is not known; it lies somewhere below the stated upper bound. The marker shows where the limit of quantification of the measurement lies relative to the parametric value.
Radiology (3)
| Parameter | Value | Parametric value | Share of the parametric value | Reference |
|---|---|---|---|---|
| Indicative dose | <0,16.) mSv/a below limit of quantification | 0.1 mSv/a | — | Single value |
| Radon-222 | <10 6.) Bq/l below limit of quantification | 100 Bq/l | — | Single value |
| Tritium | n.e. 6.) Bq/l not determined | 100 Bq/l | — | Single value |
Further parameters (7)
| Parameter | Value | Parametric value | Share of the parametric value | Reference |
|---|---|---|---|---|
| Calcium | 61,2 mg/l | — | — | Single value |
| Carbonate hardness | 8,6 °dH | — | — | Single value |
| Magnesium | 10,3 mg/l | — | — | Single value |
| Oxygen | 6,9 mg/l | — | — | Single value |
| Phosphate | <0,837 mg/l below limit of quantification | — | — | Single value |
| Potassium | 3,0 mg/l | — | — | Single value |
| Silicate / silicic acid | 14,0 mg/l | — | — | Single value |
Values taken unchanged from the publications linked below — for each parameter the most recent recorded value. „—" in the parametric value column: no currently valid legal parametric value is stored in our database for this parameter; the parameter register with all parametric values is being expanded continuously.
Source: https://stadtwerke-hilden.de/uploads/Trinkwasser_Analysewerte_2025.pdf · Stand Jan. 2026 · Jahresmittelwerte 2025 · retrieved on 11/07/2026
Postcodes in this zone: 40721
Hochbehälter Hardt
Stadtwerke DüsseldorfAssigned via the water supplier — the exact supply zone boundary within the postcode is not yet linked.
Water hardness
14.7 °dH
Hardness range hart
| Parameter | Value | Parametric value | Share of the parametric value | Reference |
|---|---|---|---|---|
| Nitrate | 13,1 mg/l | 50 mg/l | 26 % | Mean |
| Lead | <0,002 mg/l below limit of quantification | 10 µg/l | < 20 % * | Mean |
| Escherichia coli (E. coli) | 0 KBE/100 ml | 0/100 ml | — | Mean |
| Sulphate | 58,2 mg/l | 250 mg/l | 23 % | Mean |
| Sodium | 28,5 mg/l | 200 mg/l | 14 % | Mean |
* Value below the limit of quantification: the actual share of the parametric value is not known; it lies somewhere below the stated upper bound. The marker shows where the limit of quantification of the measurement lies relative to the parametric value.
Show all recorded parameters (109 — most recent value per parameter)
Microbiology (2)
| Parameter | Value | Parametric value | Share of the parametric value | Reference |
|---|---|---|---|---|
| Escherichia coli (E. coli) | 0 KBE/100 ml | 0/100 ml | — | Mean |
| Intestinal enterococci | 0 KBE/100 ml | 0/100 ml | — | Mean |
Chemical parameters (53)
| Parameter | Value | Parametric value | Share of the parametric value | Reference |
|---|---|---|---|---|
| 1,2-dichloroethane | <0,2 µg/l below limit of quantification | 3 µg/l | < 7 % * | Mean |
| 2,4-D | <0,01 µg/l below limit of quantification | — | — | Mean |
| Antimony | <0,0008 mg/l below limit of quantification | 5 µg/l | < 16 % * | Mean |
| Arsenic | <0,0009 mg/l below limit of quantification | 10 µg/l | < 9 % * | Mean |
| Atrazine | <0,01 µg/l below limit of quantification | — | — | Mean |
| Bentazone | <0,01 µg/l below limit of quantification | — | — | Mean |
| Benzene | <0,2 µg/l below limit of quantification | 1 µg/l | < 20 % * | Mean |
| Benzo(a)pyrene | <0,002 µg/l below limit of quantification | 10 ng/l | < 20 % * | Mean |
| Benzo(b)fluoranthene | <0,005 µg/l below limit of quantification | — | — | Mean |
| Benzo(ghi)perylene | <0,005 µg/l below limit of quantification | — | — | Mean |
| Benzo(k)fluoranthene | <0,005 µg/l below limit of quantification | — | — | Mean |
| Bisphenol A | <0,05 µg/l below limit of quantification | 2.5 µg/l | < 2 % * | Mean |
| Boron | <0,060 mg/l below limit of quantification | 1 mg/l | < 6 % * | Mean |
| Bromacil | <0,01 µg/l below limit of quantification | — | — | Mean |
| Bromate | 0,001 mg/l | 10 µg/l | 10 % | Mean |
| Bromodichloromethane | <0,2 µg/l below limit of quantification | — | — | Mean |
| Bromoxynil | <0,02 µg/l below limit of quantification | — | — | Mean |
| Cadmium | <0,0004 mg/l below limit of quantification | 3 µg/l | < 13 % * | Mean |
| Chloridazon | <0,01 µg/l below limit of quantification | — | — | Mean |
| Chlorotoluron | <0,01 µg/l below limit of quantification | — | — | Mean |
| Chromium | <0,001 mg/l below limit of quantification | 25 µg/l | < 4 % * | Mean |
| Copper | <0,030 mg/l below limit of quantification | 2 mg/l | < 2 % * | Mean |
| Dibromochloromethane | <0,2 µg/l below limit of quantification | — | — | Mean |
| Dichloromethane | <0,2 µg/l below limit of quantification | — | — | Mean |
| Dichlorprop | <0,01 µg/l below limit of quantification | — | — | Mean |
| Dimethenamid | <0,01 µg/l below limit of quantification | — | — | Mean |
| Diuron | <0,01 µg/l below limit of quantification | — | — | Mean |
| Fluoranthene | <0,005 µg/l below limit of quantification | — | — | Mean |
| Fluoride | 0,14 mg/l | 1.5 mg/l | 9 % | Mean |
| Indeno(1,2,3-cd)pyrene | <0,005 µg/l below limit of quantification | — | — | Mean |
| Isoproturon | <0,01 µg/l below limit of quantification | — | — | Mean |
| Lead | <0,002 mg/l below limit of quantification | 10 µg/l | < 20 % * | Mean |
| MCPA | <0,02 µg/l below limit of quantification | — | — | Mean |
| Mecoprop | <0,01 µg/l below limit of quantification | — | — | Mean |
| Mercury | <0,00001 mg/l below limit of quantification | 1 µg/l | < 1 % * | Mean |
| Metazachlor | <0,01 µg/l below limit of quantification | — | — | Mean |
| Metribuzin | <0,01 µg/l below limit of quantification | — | — | Mean |
| Nickel | <0,002 mg/l below limit of quantification | 20 µg/l | < 10 % * | Mean |
| Nitrate | 13,1 mg/l | 50 mg/l | 26 % | Mean |
| Nitrite | <0,01 mg/l below limit of quantification | 0.5 mg/l | < 2 % * | Mean |
| Pesticides — Total | <0,01 µg/l below limit of quantification | 0.5 µg/l | < 2 % * | Mean |
| Selenium | <0,002 mg/l below limit of quantification | 10 µg/l | < 20 % * | Mean |
| Simazine | <0,01 µg/l below limit of quantification | — | — | Mean |
| Tebuconazole | <0,01 µg/l below limit of quantification | — | — | Mean |
| Terbuthylazine | <0,01 µg/l below limit of quantification | — | — | Mean |
| Tetrachloroethene | <0,2 µg/l below limit of quantification | — | — | Mean |
| Tetrachloromethane | <0,2 µg/l below limit of quantification | — | — | Mean |
| Tribromomethane (bromoform) | <0,2 µg/l below limit of quantification | — | — | Mean |
| Trichloroethene | <0,2 µg/l below limit of quantification | — | — | Mean |
| Trichloromethane (chloroform) | <0,2 µg/l below limit of quantification | — | — | Mean |
| Trihalomethanes — Total | 0 µg/l | 50 µg/l | 0 % | Mean |
| Uranium | 0,0006 mg/l | 10 µg/l | 6 % | Mean |
| Vinyl chloride | <0,2 µg/l below limit of quantification | 0.5 µg/l | < 40 % * | Mean |
* Value below the limit of quantification: the actual share of the parametric value is not known; it lies somewhere below the stated upper bound. The marker shows where the limit of quantification of the measurement lies relative to the parametric value.
Metabolites (1)
| Parameter | Value | Parametric value | Share of the parametric value | Reference |
|---|---|---|---|---|
| Desphenyl-chloridazon | <0,01 µg/l below limit of quantification | — | — | Mean |
Indicator parameters (20)
| Parameter | Value | Parametric value | Share of the parametric value | Reference |
|---|---|---|---|---|
| Aluminium | <0,030 mg/l below limit of quantification | 0.2 mg/l | < 15 % * | Mean |
| Ammonium | <0,03 mg/l below limit of quantification | 0.5 mg/l | < 6 % * | Mean |
| Calcite dissolution capacity | -6,10 mg/l CaCO3 | 5 mg/l CaCO3 | — | Mean |
| Chloride | 67,9 mg/l | 250 mg/l | 27 % | Mean |
| Clostridium perfringens (including spores) | 0 KBE/100 ml | 0/100 ml | — | Mean |
| Coliform bacteria | 0 KBE/100 ml | 0/100 ml | — | Mean |
| Colony count 22 °C | 1 KBE/ml | ohne anormale Veränderung | — | Mean |
| Colony count 36 °C | 1 KBE/ml | ohne anormale Veränderung | — | Mean |
| Colour | <0,1 1/m below limit of quantification | 0.5 m⁻¹ | — | Mean |
| Conductivity (25 °C) | 699 µS/cm | 2,790 µS/cm | — | Mean |
| Iron | <0,020 mg/l below limit of quantification | 0.2 mg/l | < 10 % * | Mean |
| Manganese | <0,020 mg/l below limit of quantification | 50 µg/l | < 40 % * | Mean |
| Odour | annehmbar und ohne anormale Veränderung | für den Verbraucher annehmbar | — | Mean |
| pH | 7,50 | 6,5–9,5 | — | Mean |
| Sodium | 28,5 mg/l | 200 mg/l | 14 % | Mean |
| Sulphate | 58,2 mg/l | 250 mg/l | 23 % | Mean |
| Taste | annehmbar und ohne anormale Veränderung | für den Verbraucher annehmbar | — | Mean |
| Temperature | 14,0 °C | — | — | Mean |
| Total organic carbon (TOC) | 0,28 mg/l | ohne anormale Veränderung | — | Mean |
| Turbidity | 0,12 FNU | 1 NTU | — | Mean |
* Value below the limit of quantification: the actual share of the parametric value is not known; it lies somewhere below the stated upper bound. The marker shows where the limit of quantification of the measurement lies relative to the parametric value.
Radiology (2)
| Parameter | Value | Parametric value | Share of the parametric value | Reference |
|---|---|---|---|---|
| Gross alpha activity | < 0,025 Bhg/l below limit of quantification | — | — | Single value |
| Radon-222 | < 10 Bg/l below limit of quantification | 100 Bq/l | — | Single value |
Further parameters (31)
| Parameter | Value | Parametric value | Share of the parametric value | Reference |
|---|---|---|---|---|
| Acid capacity to pH 4.3 | 2,00 mmol/l | — | — | Mean |
| Amidotrizoic acid | 0,03 µg/l | — | — | Mean |
| Barium | 0,052 mg/l | — | — | Mean |
| Base capacity to pH 8.2 | 0,10 mmol/l | — | — | Mean |
| Benzotriazole | <0,02 µg/l below limit of quantification | — | — | Mean |
| Bezafibrate | <0,01 µg/l below limit of quantification | — | — | Mean |
| Bromide | 0,12 mg/l | — | — | Mean |
| Calcium | 1,62 mmol/l | — | — | Mean |
| Candesartan | <0,01 µg/l below limit of quantification | — | — | Mean |
| Carbamazepine | <0,01 µg/l below limit of quantification | — | — | Mean |
| Diclofenac | <0,01 µg/l below limit of quantification | — | — | Mean |
| EDTA | <0,5 µg/l below limit of quantification | — | — | Mean |
| Hardness range (WRMG) | hart | — | — | Mean |
| Hydrogen carbonate | 228 mg/l | — | — | Mean |
| Iomeprol | <0,01 µg/l below limit of quantification | — | — | Mean |
| Iopamidol | <0,01 µg/l below limit of quantification | — | — | Mean |
| Iopromide | <0,01 µg/l below limit of quantification | — | — | Mean |
| Magnesium | 0,36 mmol/l | — | — | Mean |
| Metformin | <0,01 µg/l below limit of quantification | — | — | Mean |
| Oxipurinol | <0,02 µg/l below limit of quantification | — | — | Mean |
| Oxygen | 8,30 mg/l | — | — | Mean |
| Pentoxifylline | <0,01 µg/l below limit of quantification | — | — | Mean |
| Phosphate | <0,07 mg/l below limit of quantification | — | — | Mean |
| Potassium | 3,30 mg/l | — | — | Mean |
| Sotalol | <0,01 µg/l below limit of quantification | — | — | Mean |
| Strontium | 0,453 mg/l | — | — | Mean |
| Sulfamethoxazole | <0,01 µg/l below limit of quantification | — | — | Mean |
| Thallium | <0,002 mg/l below limit of quantification | — | — | Mean |
| Total hardness | 2,62 mmol/l | — | — | Mean |
| Trimethoprim | <0,01 µg/l below limit of quantification | — | — | Mean |
| Zinc | <0,010 mg/l below limit of quantification | — | — | Mean |
Values taken unchanged from the publications linked below — for each parameter the most recent recorded value. „—" in the parametric value column: no currently valid legal parametric value is stored in our database for this parameter; the parameter register with all parametric values is being expanded continuously.
Source: https://www.swd-ag.de/pk/strom-gas-wasser/wasser/trinkwasseranalyse/ · 01.01.2025 – 31.12.2025 · retrieved on 13/07/2026
Postcodes in this zone: 40721
Frequently asked questions about drinking water in Hilden, Düsseldorf
- How hard is the water in Hilden, Düsseldorf?
- Stadtwerke Düsseldorf publishes a total hardness of 2,62 mmol/l for the supply zone Hochbehälter Hardt (Düsseldorf und Mettmann) — that corresponds to 14.7 °dH. The hardness range is a classification under the German Detergents and Cleaning Products Act (soft below 8,4 °dH, medium 8,4 to 14 °dH, hard above that) and not a quality verdict — it indicates how much calcium and magnesium is dissolved in the water. Basis: Publication by the water supplier, retrieved on 11/07/2026.
- How much nitrate is in the drinking water in Hilden, Düsseldorf?
- Stadtwerke Düsseldorf publishes a nitrate value of 13,1 mg/l for the supply zone Hochbehälter Hardt (Düsseldorf und Mettmann). The statutory parametric value is 50 mg/l; the measured value represents 26 % of the parametric value. Basis: Publication by the water supplier, retrieved on 11/07/2026.
- Who supplies the drinking water in Hilden, Düsseldorf?
- Stadtwerke Düsseldorf. The values shown here come from the supply zone Hochbehälter Hardt (Düsseldorf und Mettmann) and apply to the water the supplier delivers. What happens between the building connection and the tap — in old lead pipes, for example — is not covered by these analyses; information on that is provided by owners, the health authority or an examination by an accredited laboratory.
General questions — how current the data is, limit of quantification, parametric values, who is behind this site — are answered under Questions & answers.