Quality of the drinking water

Drinking water quality and groundwater protection are two sides of the same coin. Only foresighted, careful protection of the groundwater guarantees consistent, high quality of the drinking water.

Drinking water quality at the highest level

The supply of drinking water to the population is subject to the very strict provisions of the German drinking water ordinance. In the course of the drinking water analysis, over 100 individual parameters are investigated.

In addition to the standard analytics of the drinking water supply, many elaborate and complex chemical-physical and microbiological processes are available for trace substance analytics in the company and research laboratory of the Landeswasserversorgung. Mass spectrometric analysis methods and biological testing systems with the aid of luminescent bacteria, enzymes or genetically modified yeast cells reflect the latest development status.

The quality control of the Landeswasserversorgung comprises around 400,000 individual analyses per year, many online measurements in the entire supply network, and an extensive safety concept. Around 40 highly qualified employees in the Landeswasserversorgung company and research laboratory are available for these tasks. Furthermore, they work on other process developments as part of various research projects.

Operation and research laboratory of the Landeswasserversorgung

Drinking water analysis in brief
The annual mean values 2021 for your city/municipality

The Landeswasserversorgung supplies around 3 million people in Baden-Württemberg and Bavaria, from A for Aalen to Z for Ziertheim. Are you interested in the annual mean values for your city/community?

Drinking water analysis in summary (2021)

Parameter Dimension Limit according to drinking
water ordinance
pH value 7,65 at 13,9 °C ≥ 6,5 and ≤ 9,5
Calcium 75 mg/L -
Chloride 34,5 mg/L 250 mg/L
Iron < 0,01 mg/L 0,200 mg/L
Magnesium 11,7 mg/L -
Sodium 13,6 mg/L 200 mg/L
Sulphate 26,3 mg/L 250 mg/L
Lead < 0,0005 mg/L 0,010 mg/L
Fluoride 0,06 mg/L 1,5 mg/L
Nitrate 21,5 mg/L 50 mg/L
Polycyclic aromatic hydrocarbons < 0,0001 mg/L 0,00010 mg/L
Plant protection products and biocidal products < 0,00005 mg/L 0,00010 mg/L
Total individual substances < 0,0001 mg/L 0,00050 mg/L
Carbonate hardness 9,8 °dH -
Total hardness 13,2 °dH -
Total alkaline earths 2,37 mol/m³ -
Hardness range medium -


The values given refer to the drinking water of the state water supply. Your city or municipality may use its own drinking water sources and mix its own water with the drinking water of the LW. You can obtain the current drinking water analysis for your place of residence from your city or municipal administration or from the responsible public utility company.

Drinking water analysis in summary (2021)

Parameter Dimension Limit according to drinking
water ordinance
pH value 7,61 at 10,4 °C ≥ 6,5 and ≤ 9,5
Calcium 74 mg/L -
Chloride 21,7 mg/L 250 mg/L
Iron < 0,01 mg/L 0,200 mg/L
Magnesium 9,3 mg/L -
Sodium 7,2 mg/L 200 mg/L
Sulphate 13,1 mg/L 250 mg/L
Lead < 0,0005 mg/L 0,010 mg/L
Fluoride 0,05 mg/L 1,5 mg/L
Nitrate 31,1 mg/L 50 mg/L
Polycyclic aromatic hydrocarbons < 0,0001 mg/L 0,00010 mg/L
Plant protection products and biocidal products < 0,00005 mg/L 0,00010 mg/L
Total individual substances < 0,0001 mg/L 0,00050 mg/L
Carbonate hardness 9,6 °dH -
Total hardness 12,6 °dH -
Total alkaline earths 2,26 mol/m³ -
Hardness range medium -


The values given refer to the drinking water of the state water supply. Your city or municipality may use its own drinking water sources and mix its own water with the drinking water of the LW. You can obtain the current drinking water analysis for your place of residence from your city or municipal administration or from the responsible public utility company.

Drinking water analysis in summary (2021)

Parameter Dimension Limit according to drinking
water ordinance
pH value 8,03 at 7,0 °C ≥ 6,5 and ≤ 9,5
Calcium 51 mg/L -
Chloride 7,9 mg/L 250 mg/L
Iron 0,005 mg/L 0,200 mg/L
Magnesium 8,6 mg/L -
Sodium 5,8 mg/L 200 mg/L
Sulphate 34,0 mg/L 250 mg/L
Lead < 0,005 mg/L 0,010 mg/L
Fluoride 0,1 mg/L 1,5 mg/L
Nitrate 4,1 mg/L 50 mg/L
Polycyclic aromatic hydrocarbons < 0,0001 mg/L 0,00010 mg/L
Plant protection products and biocidal products < 0,00005 mg/L 0,00010 mg/L
Total individual substances < 0,0001 mg/L 0,00050 mg/L
Carbonate hardness 7,3 °dH -
Total hardness 9,1 °dH -
Total alkaline earths 1,63 mol/m³ -
Hardness range medium -


The values given refer to the drinking water of the state water supply. Your city or municipality may use its own drinking water sources and mix its own water with the drinking water of the LW. You can obtain the current drinking water analysis for your place of residence from your city or municipal administration or from the responsible public utility company.

If you are interested in the current, complete analysis of the LW drinking water, you can view or download it here. The different supply areas (VB1, VB2, VB3) are marked in color. Their allocation to the supply area of the Landeswasserversorgung can be seen in the map below.

The analyzed measured values usually change only slightly from year to year.

Current drinking water analysis (accessible)

Drinking water – Because of the elaborate and regular investigations, it is one of the best controlled foodstuffs

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Water protection areas – The key to success

To protect the groundwater reserves, the catchment areas of the container systems are designated as water protection areas. The protection areas here are divided into three zones. The outer protection zone should cover the entire catchment area of the drinking water springs. From the edge of the inner protection zone, the flow time to the springs should be at least 50 days. The container area delimits the direct surroundings of the extraction plants.

Different legal requirements apply for the individual protection zone areas with respect to construction, agricultural and other use. Whereas most uses are possible with certain restrictions in the outer water protection zone, construction for example is not permitted in the inner protection zone. Agricultural land use is permitted here only with strict

conditions. In general, any use of the container area is excluded. The water protection areas are monitored regularly to check the various requirements.

Because of the particular geological conditions in the Swabian Alb region, the heavily karstified subsurface and the resulting very high flow speeds at some times and in some areas, large areas of the high plateau of Swabian Alb are designated as water protection areas. With a total area of around 800 square kilometres, the protection areas for the extraction plants of the state water supply, the waterworks at Langenau, at Dischingen and at Burgberg are among the largest contiguous water protection areas in the Federal Republic of Germany.

Groundwater – A treasure needs to be guarded

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