Planning the underground: managing sustainable use of the Dutch underground with specific reference to aquifer thermal energy storage

During the last decades, the pressure for space in dense urbanized areas has led to an increasing use of the underground for a variety of functions such as infrastructure, utilities and buildings. In the last decade, an exponential growth in systems using the underground for thermal energy storage fueled by the need for renewable energy sources is added to this. These relative novel underground functions can compete with existing users of the underground. This includes both active (e.g. drinking water) and passive (groundwater dependent ecosystems) users of these so called ecosystems services. Dutch policy makers of various governmental levels (municipality, province, national) are currently exploring methods to deal with these conflicting interests. A few examples of issues to deal with are: 1) how do we deal with existing rights versus new claims for the underground? 2) how do we manage the exponential growth of subsurface functions of which the long-term environmental effects are unknown? KWR and University Utrecht have recently started a project funded by the Dutch Ministry of Housing, Spatial Planning and the Environment investigating these questions. In this project we will look at both the technical and legal aspects of subsurface planning and specifically focus on underground thermal energy storage in spatial planning. This extended abstract details the preliminary results of this project.