The implementation of tariffs and fees in water resources management is subject to numerous requirements, which result on the one hand from water-legal and on the other hand from statutory regulations. Supporting municipalities and water associations in the development of models for the allocation of costs in the calculation of fees and tariffs, we focus in particular on the distribution of burdens according to the polluter-pays principle.
The scientific support of the development and optimization of water tariffs and fees begins with an analysis of the current situation and the determination of the need for action. For this purpose, existing data are specifically processed and evaluated. It is necessary to investigate whether water management, technical or legal requirements and framework conditions and thus cost and usage structures have changed. We suggest fee and tariff models, in particular for the areas of wastewater disposal and water management, and support municipalities and water associations by conducting working groups and informing citizens and members.
A regular review of the assessment models against the background of a polluter-pays cost allocation can make a valuable contribution to an overall sustainable water management.
Municipalities normally impose wastewater charges on the basis of the freshwater scale, which provides a purely volume-based assessment. However, this scale is not always conform with the requirement of a polluter-pays principle. If commercial / industrial indirect dischargers, whose wastewater often differs significantly from domestic wastewater, account for a not insignificant share of at least 10 % of the total volume of wastewater, the freshwater scale may no longer be suitable for adequately reflecting the polluter-pays principle. In these cases, an alternative charging model must be developed, taking into account so-called heavy polluter surcharges, which consider the composition of the wastewater and the associated load on the wastewater treatment plants of different indirect dischargers. This is done with the aim of not overcharging domestic wastewater in comparison to the more heavily polluted industrial wastewater.
Increasingly, municipalities are faced with the task of enacting charging statutes for the area of water bodies. However, the municipalities can only allocate the share of watercourse maintenance costs that serves to maintain and secure the proper condition for water runoff. Costs of watercourse maintenance that contribute to the ecological development of the watercourse, on the other hand, are generally not directly chargeable and must be taken into account accordingly in the design of the charging model. Moreover, a proper cost allocation requires a consideration of the respective influences on the water bodies to be maintained and the resulting costs.
In North Rhine-Westphalia, for example, large areas are significantly affected by mining activities. The resulting subsidence poses particular challenges for water management and thus for the development of models for a fair distribution of costs.