Amendments to the Drinking Water Ordinance: Legionellae in Hot Water Systems - Data from the Public Health Authority Frankfurt am Main, Germany

Background: The first and second amendment to the Drinking Water Ordinance came in to force in the years 2011 and 2012 causing additional tasks and responsibilities for operators of commercial large-scale systems, usually hot water systems in large residential buildings, and for the local health authorities. This article describes the experiences of the health authority in Frankfurt/Main with these new regulations. Some of the revisions in the first amendment of the ordinance (TrinkwV 2001 (2011)) were omitted in the second revision (TrinkwV 2001 (2012)) such as the obligation to notify for large-scale systems. Furthermore, the intervals between the obligatory inspections were extended from 1 to 3 years and merely exceedances of the legal limits were to be notified in contrast to the previous obligation to notify all values. Results: On the basis of the TrinkwV 2001 (2011) a large additional staff requirement had been estimated (13/21 positions). After the TrinkwV 2001 (2012) the tasks can be accomplished by less than 2 employees. While the notification obligation was still in force, the health authority received 4461 notifications of large-scale systems, since then a further 477 have been notified. Of a total of 1335 initial analyses, 794 (60%) exceeded the technical action value and in 113 properties with values exceeding 10000/100 ml a usage restriction was necessary. Conclusions: Due to the suspension of the notification obligation to report any result of the analyses performed the assessment of the reports on large-scale systems has become difficult. An appropriate assessment of the implementation of the regulation is not possible, since the total number of large-scale systems is not known and a failure to report may result from a measured value below the technical action value as well as from a not inspected system. The large number of usage restrictions is an indication for the necessity to inspect and if required to treat and restore the system.