Opening up the subsurface for the cities of tomorrow. The Subsurface in the planning process.

COST (European Cooperation in Science and Technology) Action TU1206 Sub-Urban has explored sustainable use and management of the urban subsurface, and the use of subsurface information in urban planning and development. A part of the Action (Working Group 1) has assessed the 'state-of-art' in cities; another part (Working Group 2) has evaluated practices and techniques. Both have considered access to subsurface knowledge in cities. A network was established by the Action with more than 100 participants in total; and in Working Group 2, there were more than 50 participants. Working Group 2 has resulted in 6 full reports and a summary report. The Action's Working Group 1 undertook comprehensive city studies. These established that the subsurface was in effect virtually 'Out of mind, out of sight' with respect to planning and management and there was a significant knowledge gap to fill. The task for Working Group 2 was to improve this situation. This paper is based on the work drawn together in the Working Group 2 Summary report 'Opening up the subsurface for the cities of tomorrow'. This deals with good practices in urban subsurface planning and management; and how the urban subsurface planning and management processes can be improved in the future.