Although the status detection of water bodies regarding ecological and chemical aspects has clearly improved in the course of the Water Framework Directory, there are still no appropriate time series concerning the overall development of water quality in Germany. Moreover, the chemical water quality is simply expressed in the dichotomy “good” or “bad”, whereas the ecological quality is at least differentiated in five categories, which cannot be directly monetized.
Because of the Water Framework Directory’s requirement to attribute costs of water services, including environmental and resource costs according to the “polluter pays principle” and thus, internalize former external environmental cost, there is increasing effort to improve economic valuation methods. Thus, in the course of the research program “Aqua Money”, a handbook for the quantification of environmental and resource costs was published. For demonstration purposes, the handbook inter alia estimated the willingness to pay for the amelioration of river water quality (with a length of 1606 km) towards a “good ecological level”: The result of 792,6 million US-Dollar (price basis 2007) however comes along with numerous methodological problems.
Even though a significant improvement of the data situation is to be expected in the near future, the current data has merely the quality of a planned item that has to be regarded as very low since its coverage is limited to a small fraction of all water bodies. However, in the absence of good data the value is preliminary taken as a fixed amount. The disclosed amount of 792,6 Million is converted to Euros in the year 2010.