Exceedences of limit values in 1-2% of the surveillance measurements occurred only in testing for coliform bacteria throughout the entire report period. In respect of nitrate, the new data confirms the downward trend at a rate of 1.1. percent exceedence already observed in 1999: down to 0.08 percent in 2007-- with only a temporary break from the downward tendency in 2006 (1.3%).
When limit values are exceeded there is not always an immediate risk to public health as this depends on parameters as well as the level and duration of the exceedence. For example, the occurrence of coliform bacteria in drinking water indicates a general deterioration of water quality and thus the need for further tests to identify the cause and initiate preventive measures to protect public health. Exceedence for the parameter lead, for example, is an indication of the presence of old lead pipes in the drinking water installation or in fixtures that do not meet the generally accepted codes of practice.
Should limit values be exceeded, detection and elimination of cause takes priority over measures to combat symptoms. The public health office in charge must check whether the exceedence poses a risk to health and requires immediate action, or whether it can be tolerated short-term until measures to eliminate the cause can be taken.
Drinking water is the most vital of all foods. It also serves household purposes of personal hygiene, laundering or toilet flushing. Drinking water quality must meet high standards in Germany. The Drinking Water Ordinance (TrinkwV 2001), which transposed the 1998 EC Drinking Water Directive into national law, prescribes these standards. Some of the basic requirements stipulate that drinking water must not only be free of pathogens and substances in concentrations that may be harmful to health, it must also be ”wholesome and clean”.
The Drinking Water Ordinance (TrinkwV 2001) also regulates the obligations of the utilities and monitoring authorities whilst determining the microbiological and chemical parameters to be tested as well as the intervals for monitoring of drinking water. In order to assure the hygienic safety of drinking water the ordinance also requires that limit values and requirements concerning the condition of water at the household tap are complied with.
The EC drinking water directive commits all Member States to submit a report on drinking water every three years. The authorities conferred with responsibility for these duties in Germany are the BMG and UBA. The report is based on measurements taken at all 2,624 large water utilities in Germany. On average these utilities provide more than 1,000 cubic metres (m³) water per day; that is, they supply more than 5,000 people. Altogether these installations distribute roughly 4.5 million m³ drinking water annually, supplying some 65.5 million individuals, or 80 percent of the population of Germany.
For more information on drinking water that goes beyond the scope of the information in the reports, consumers may address enquiries to their local health offices or to the district water utility.
Dessau-Roßlau, 2 April 2009
